Subwoofers: Advantages vs Disadvantages ?

[iasomph]

I've recently launched a thread about high-end monitors. As I mentioned in that thread I was skeptical about Sub's and wanted to avoid them in my final choice. Honestly I never used them but I've read many times advices here from experts that sub's may do more harm than good most of the time.

However, after reading the (great as always Hugh!) review of the PMC TwoTwo Sub1, my mind unexpectedly started to consider also this option. The reviewer pointed out that the integration in the room with this model was not very difficult, so....I have some further questions about subs:

1) Is it better to use sub designed for specific speakers models? For example the PMC TwoTwo Sub1 was designed to be used with PMC TwoTwo monitors....this is maybe one of the secret of the easier integration and good result of this sub in the room ?

2) Is it possible to mix different technologies? I mean...for example using a pair of ported monitor speakers and then adding a sub with ATL technology - or a sealed one? Or, again, is it better to stay with the same technology to get consistent results/phase and timing?

3) Referring to the PMC TwoTwo Sub1: is it possible to turn it on and off quickly while listening (with just a push of a button) without having to configure it each time, disconnecting cables, etc...? I'm thinking about a scenario in which I work most of the time with just the TwoTwo 6 speakers, but I also have the ability to switch the Sub1 on when I want to check the low end spectrum and have a better idea of what's happening down there...or also how the tracks will play in a PA club system. This flexibility could actually be a good thing for dance music composers/mixers like me.

4) Can I choose "how low" the Sub1 can go? For example, if my new room will have some problems with 20 to 35hz and I cannot manage to solve these problems with acoustic treatment, may I choose that the sub goes down for example to just 35Hz?

5) Threeways (like KH310A) vs 2.1 high quality solutions (like TwoTwo6 with their Sub1): what is the advantage of staying with the threeways compared with the other solution?

6) In case I want to also start to offer online mastering services later, would be more useful a threeway system like the KH310A or the TwoTwo 6 + Sub1 can give me a real competitive advantage in this regard? May this solution be more attractive and effective for dance music producers looking for mastering services for their tracks?

I don't know why I suddenly started to think about subs. I think the main reason is that , if it would be possible to integrate without too problems into the room, the sub would give me more flexibility. For example I can choose how much sub volume to turn on to suit my taste (while on threeways or simple stereo monitor systems I just have to accept how they sound), or turn it on only in some situations....so better ask these questions and understand more about subs before making my big next purchase!

I think it's enough for now, thanks for your help as usual

[Jack Ruston]

There are two reasons good reasons for buying a sub.

1. You require an LFE for a surround rig.

2. You're working with electronic music producers, who during tracking want to feel the low end in the room more.

It's very difficult to use a sub as part of an accurate critical listening setup. When it does work, it's usually because they (there will be two) are integrated into the design of the room. What you're FAR more likely to benefit from is simply a full range speaker design, that incorporates drivers and cabinets capable of producing that sort of low end. It sounds to me from reading your posts that you have the sort of budget that might be necessary. For what it's worth I'd STRONGLY recommend that you audition an Amphion Base 125 with Two 18's setup. The way the low end joins up with the midrange, and in fact the way the mid and highs join up is very hard to beat in that system...There are other options of course. You are then able to turn the lowest octave off if needs be, and as you say it can be adjusted for level (as it almost always can).

J

[iasomph]

Hi Jack,

thanks for your precious contribute! I often read your posts and you are one of the competent names that I see often in this forum! Amphion Two18 with BaseOne25 system is indeed an impressive combo. It seems this system has been recently purchased by one of the most experienced and good mixer in the world...so if't good for him. it would certainly be good for anyone else! However it could not work for me for two reasons:

- unfortunately my budget is not that high. The whole system would cost me 13.000€ !!! So much more than the 4.500 (that can be slight exceeded) budget that I initially thought.

- also, the place where I'll probably place monitors have some space constraints (especially in respect to height, due to the descending cieling), and the Two18 monitors can be used only vertically....so they would not fit there. I may consider the BaseOne25 + One15 or One18 (used horizontally)...but again, I would be in the 9.000-10.500€ range and again, I'm afraid that the BaseOne25 would be aybe still too high for that place.

When I speak about PMC TwoTwo6 + Sub1 combo, please consider the discount I can have this month on them...I could buy them together fot about 6.500€ (or 5.700€ for TwoTwo 5 + Sub1). This is already far more than I initially expected to pay...but I can think to stretch to this amount in case this would be undoubtely the best choice and investment for my future needs (edm composing + mixing + online mastering services). Of course, after this month, I could not afford to buy them at full price because it would be 8.800€ for the TwoTwo 6 + Sub1 combo! Definitely too much for me!

Also, the very competent John Willet suggested me the Neumann KH805 sub in the other thread. At the beginning I didn't considered too much his suggestion (I also thought he was speaking of the KH810 that I knew was very expensive..I wasn't aware of this new product from Neumann! And my brain wasn't considering subs option at that time...and I still had to read Hugh Robjohns review of the Sub1! ). Actually the KH805 cost "only" 1.500€ and would transform the KH120A into a new beast. Also, it seems it can be turned on/off with just a foot switch or a button. And this would be a very convenient thing....something I also hope the PMC Sub1 have!

Anyway, I'm not sure the KH805 has all the convenient settings that the Sub1 has for a perfect - or at least easier - integration in the room (it seems that KH805 phase can be rotated with 45° steps, while the PMC Sub1 can be rotated with 5° steps...so with much more precision to obtain a perfect integration. Also, the cutoff for the KH805 is fixed at 80hz, while the PMC Sub1 can adapt to different cutoff and slopes. This seems another useful thing. Please correct me if I say uncorrect things, since I'm not expert at all about Subs and actualy never actually placed one in my room).

Also, the PMC use ATL technology, that Sub1 should work very good also at low volumes. The KH805 is ported, so I'm not sure it would work perfectly and consistently at different volume levels...especially at low listening levels. But then....the difference in price between buying the TwoTwo6 + Sub1 vs. just buying the KH805 is amazingly big! So..it certainly worth investigating. I like the idea of investing in new amazing monitoring gear, but if I can obtain amazing results with just the KH120A + KH805....I'm the first to be happy to save so much cash!

By the way you descouraged me a little when speaking that it's better having 2 subs. I could also stretch to buy 2xKH805...but I don't have so much space in the room! It would be almost phisically impossible!

[The Red Bladder]

1) Is it better to use sub designed for specific speakers models? For example the PMC TwoTwo Sub1 was designed to be used with PMC TwoTwo monitors....this is maybe one of the secret of the easier integration and good result of this sub in the room ?

2) Is it possible to mix different technologies? I mean...for example using a pair of ported monitor speakers and then adding a sub with ATL technology - or a sealed one? Or, again, is it better to stay with the same technology to get consistent results/phase and timing?

3) Referring to the PMC TwoTwo Sub1: is it possible to turn it on and off quickly while listening (with just a push of a button) without having to configure it each time, disconnecting cables, etc...? I'm thinking about a scenario in which I work most of the time with just the TwoTwo 6 speakers, but I also have the ability to switch the Sub1 on when I want to check the low end spectrum and have a better idea of what's happening down there...or also how the tracks will play in a PA club system. This flexibility could actually be a good thing for dance music composers/mixers like me.

4) Can I choose "how low" the Sub1 can go? For example, if my new room will have some problems with 20 to 35hz and I cannot manage to solve these problems with acoustic treatment, may I choose that the sub goes down for example to just 35Hz?

5) Threeways (like KH310A) vs 2.1 high quality solutions (like TwoTwo6 with their Sub1): what is the advantage of staying with the threeways compared with the other solution?

6) In case I want to also start to offer online mastering services later, would be more useful a threeway system like the KH310A or the TwoTwo 6 + Sub1 can give me a real competitive advantage in this regard? May this solution be more attractive and effective for dance music producers looking for mastering services for their tracks?

1. Usually yes, but I mix double Genelec subs with Genelec, B&W and M&K in one room and two different M&Ks with one M&K sub in the main room. It's really a matter of 'suck-it-and-see'!

2. Same as one, suck-it-and-see, or rather hear!

3. Yes, it's called an on/off switch!

4. Either with an EQ or a sophisticated controller - though my advice would be to leave it alone.

5. None whatsoever. I always prefer a sub or even two. A couple of subs in one corner gives you the bass from one source, whereas two bass drivers hanging in the middle of the room where imaging of mids and highs is best can lead to bass problems, especially in small rooms.

6. Given that you imply having room problems and are unsure about speaker configurations, mastering is something you should be thinking about after another decade or two of experience and in a nice, large room that does not give you hot-spots.

Mixing and mastering room need to be at least 30 sq m. Anything below 20 sq m is destined to sound dreadful and boxy.

[Hugh Robjohns]

Ooh! What a lot of questions... but I'll have a go at answering some of them!

I've read many times advices here from experts that sub's may do more harm than good most of the time.

That's a bit of an oversimplification. There are plenty of situations in which a subwoofer (or two) can be beneficial, and of course there are many 2.1 systems which have to use a subwoofer by design.

In my experience, though, the problems come when either the subwoofer is a poor design (which can lead to 'one-note bass' and/or veiling of the midrange on the main speakers through bass distortion), or the subwoofer is set up incorrectly, or the room has such poor acoustics that all that deep bass just makes accurate monitoring utterly impossible.

Lots of people decide they want 'club-style' bass in their bedroom studios, but don't have the necessary acoustic treatment to cope with it, don't have the budget to buy a decent subwoofer, and don't have the knowledge or experience to set the thing up properly either. That's just a recipe for disaster and angry neighbours!

The result -- and I've heard this so many times -- is an exaggerated, lumpy bass that gets in the way of the music instead of enhancing it -- in other words, more harm than good!

So, before you think of going down the subwoofer route you must first:

(a) Thoroughly deal with all standing wave resonances in the room acoustics -- which is a lot easier to type than to achieve! A few foam 'bass traps' ain't gonna cut it!

(b) Be prepared to spend A LOT of money on a high quality subwoofer (to ensure minimal harmonic distortion) and a flat response. (We're talking £2500 and upwards). Also bear in mind that you might well need two subs to get really good flat response in the room!

(c) Be ready to spend some time fine-tuning the system to optimise the integration.

(d) Be realistic about what is practical and achievable. No domestic room is ever going to be flat to 20Hz no matter what you do!

Is it better to use sub designed for specific speakers models?

Yes, in so far as the manufacturer will already have worked out the appropriate crossover frequencies and slopes to optimise the integration. But a high quality sub will usually incorporate sufficient controls to adjust the crossover frequency, phase, level, and slope and allow the user to optimise the integration with any speaker -- and that's made a lot easier with the appropriate tools to measure and align the settings objectively in the room.

Is it possible to mix different technologies?

Yes, it is possible... but the results might not be ideal. Most decent high-end subs have pretty good time-domain responses regarless of the cabinet technology, but avoid cheap ported subs!

Referring to the PMC TwoTwo Sub1: is it possible to turn it on and off quickly while listening (with just a push of a button) without having to configure it each time, disconnecting cables, etc...?

Not on the sub 1 itself (other than the mains switch!), but I think this is possible if you also buy the system remote controller, as you can program different preset configurations and switch between them. You could alternatively run the sub from an appropriate monitor controller and switch the relevant output on and off from there. The other issue, though, is the need to switch off any high-pass filtering in the satellite speakers at the same time... which is often much harder to achieve!

However, although this sub-kill switch idea is quite common, I've never found it very helpful in practice. Either the monitoring system is accurate or it's not. If it *is* accurate, why would you want to lop off the bottom few octaves? And if it's not, how are a couple of octaves of misleading bass from a sub going to help?

I'm thinking about a scenario in which I work most of the time with just the TwoTwo 6 speakers, but I also have the ability to switch the Sub1 on when I want to check the low end spectrum and have a better idea of what's happening down there...

You'd probably be better off buying some decent headphones and using them to check the low end, free from any misleading room standing waves!

or also how the tracks will play in a PA club system. This flexibility could actually be a good thing for dance music composers/mixers like me.

Only if you have a club-sized studio or a really-good project studio with a professionally-designed acoustic treatment installation to properly control the low end.

Can I choose "how low" the Sub1 can go?

Yes, but not easily -- it would require extra processing in the signal path. Most subs have a low-pass filter, to determine the crossover integration with the satellite speakers, but not a high-pass filter to avoid exciting room modes!

Threeways (like KH310A) vs 2.1 high quality solutions (like TwoTwo6 with their Sub1): what is the advantage of staying with the threeways compared with the other solution?

Swings and roundabouts. Both approaches are valid and have both benefits and compromises. With a three-way, you have to place the speakers to optimise the stereo image, but that could put the bass drivers in less-than-ideal places with respect to the room modes. Having a separate subwoofer affords the freedom to place the sub where it suits the room, without compromising the stereo image. On the other hand, you then have a host of issues to deal with in integrating the remote sub with the satellites...

In case I want to also start to offer online mastering services later, would be more useful a threeway system like the KH310A or the TwoTwo 6 + Sub1 can give me a real competitive advantage in this regard?

It's not the speaker that will give you a competitive advantage, it's whether the speaker will enable you to hear what's going on and process it appropriately. Often a system which is a little lean but doesn't excite the room modes can allow better appreciation of what's going on rather than one that sounds exciting as it flaps the trousers but misleads as to what's really going on!

...the sub would give me more flexibility. For example I can choose how much sub volume to turn on to suit my taste (while on threeways or simple stereo monitor systems I just have to accept how they sound), or turn it on only in some situations....

I can only repeat what I said earlier: a monitoring system is supposed to provide a reliable, consistent reference. If you have to change the level of the sub 'to suit your taste' something is very wrong with the monitoring as a whole. It's either balanced and right... or it's not!

For what it's worth, given the option of the twotwo6/sub 1 or KH310 (amongst a few other high-end monitor systems) , I chose the latter and I have no regrets. And I don't envisage any need to add a sub to the system, either. I'm a fan of PMC generally and the twotwo6 is a great monitor, but I felt for mastering and quality assurance monitoring the KH310s were a better choice for me -- although I don't work with EDM; it's nearly all classical/acoustic stuff. However, I do have a TLE1 sub (the previous analogue model to the Sub 1) which I use for the LFE role with my big PMC system, and it is a very good and versatile sub...

H

[Hugh Robjohns]

Actually the KH805 cost "only" 1.500€ and would transform the KH120A into a new beast.

It certainly would!

it seems that KH805 phase can be rotated with 45° steps, while the PMC Sub1 can be rotated with 5° steps...so with much more precision to obtain a perfect integration.

And most Genelec subs only give 90 degree steps... I'm not sure you'd notice much practical difference, to be honest.

Also, the cutoff for the KH805 is fixed at 80hz, while the PMC Sub1 can adapt to different cutoff and slopes.

Yes... but the Sub1 is designed to be usable with several different monitors, and it's very easy to include options in the software. The KH is designed to be used with a very specific set of monitors, so it's going to work just fine!

By the way you descouraged me a little when speaking that it's better having 2 subs.

It comes down to the room acoustics again. Often, where there are problems with room modes, one sub can't provide a completely flat response in room, and a second one is necessary to help 'fill in' the gaps! It's a very common solution.

H

[iasomph]

Hi Hugh, as always thanks for your precious help and time in replying to all these questions

Lots of people decide they want 'club-style' bass in their bedroom studios, but don't have the necessary acoustic treatment to cope with it, don't have the budget to buy a decent subwoofer, and don't have the knowledge or experience to set the thing up properly either. That's just a recipe for disaster and angry neighbours!

Sure. I've already planned about 2.500€ budget for acoustic treatment with GIK. They are very good guys. You think this budget can be enough for taming the most important problems in the room? I also own the excellent Sonarworks plugin, and have to say that even for my current untreated room, it does miracles. Of course, with this new room I want to first do acoustic treatment and use it as a final touch to make it work less hard.

The result -- and I've heard this so many times -- is an exaggerated, lumpy bass that gets in the way of the music instead of enhancing it -- in other words, more harm than good!

I don't want a sub (or full range monitors like KH310A or similar) for reaching high spl levels! But since I found myself always boosting sub's regions on kickdrums/bass in order to get a more "club" feeling on the KH120A, I think that hearing those frequencies better would help me in taking better mixing decisions! Also, I often turn up the volume on the KH120 trying to understand more what's happening in the sub regions (30-50hz)...so hearing those regions more clearly would bring me to monitor things lower, I think!

(b) Be prepared to spend A LOT of money on a high quality subwoofer (to ensure minimal harmonic distortion) and a flat response. (We're talking £2500 and upwards). Also bear in mind that you might well need two subs to get really good flat response in the room!

(d) Be realistic about what is practical and achievable. No domestic room is ever going to be flat to 20Hz no matter what you do!

Sure. So you think the KH805, costing only 1.500€(half of 2.500£ you suggested) is too cheap to achieve optimal results?

Yes, in so far as the manufacturer will already have worked out the appropriate crossover frequencies and slopes to optimise the integration. But a high quality sub will usually incorporate sufficient controls to adjust the crossover frequency, phase, level, and slope and allow the user to optimise the integration with any speaker -- and that's made a lot easier with the appropriate tools to measure and align the settings objectively in the room.

Which are these tools?

Most decent high-end subs have pretty good time-domain responses regarless of the cabinet technology, but avoid cheap ported subs!

KH805 is ported, while KH310A are sealed. Would you use them in conjunction? Also, KH805 is ported....expensive enough to work well and even at all listening levels?

Not on the sub 1 itself (other than the mains switch!), but I think this is possible if you also buy the system remote controller, as you can program different preset configurations and switch between them. You could alternatively run the sub from an appropriate monitor controller and switch the relevant output on and off from there. The other issue, though, is the need to switch off any high-pass filtering in the satellite speakers at the same time... which is often much harder to achieve!

I'm a little surprised that on a 3.600€ sub you can't do this! The KH805 seems to do all this - also disabling the high pass filterning in the satellite speakers - at the touch of a button/footswitch. If this is possible with the same ease with the PMC Sub1 (even if it is needed their remote controller) it would be much more useful!

However, although this sub-kill switch idea is quite common, I've never found it very helpful in practice. Either the monitoring system is accurate or it's not. If it *is* accurate, why would you want to lop off the bottom few octaves? And if it's not, how are a couple of octaves of misleading bass from a sub going to help?

I've made acoustic isolation works in this room: the floor and the neighbour wall are decoupled and have been isolated very well. However sometimes you may want a more relaxed sound (without all that much lowend) or you want to concentrate more on the midrange...so disabling that low frequencies could be nice sometimes, don't you think so? Also, despite the isolation works, disabling the subs could be good for mixing and producing at evening I think. It's like - more or less - the concept of the Focal Trio6 Be!

You'd probably be better off buying some decent headphones and using them to check the low end, free from any misleading room standing waves!

I already have the HD650 with Sonaworks plugin, but while I think they are a nice combo to mix on (speaking about headphones, of course. I usually prefer speakers, especially for EDM), I've never succeded in find headphones useful for judging sub frequencies. I always end up turning up the listening levels too much and getting ear fatigue earlier. Maybe it's just me but I think that Sub stuff should also be "feeled" a little more phisically. Probably the Subpac S2 could be a better choice for this, but it's not easy to set it up with Sonarworks plugin...

Only if you have a club-sized studio or a really-good project studio with a professionally-designed acoustic treatment installation to properly control the low end.

The room is not big but hopefully the 2.500€to spend with GIK and the Sonarworks plugin may help in this regard?

Yes, but not easily -- it would require extra processing in the signal path. Most subs have a low-pass filter, to determine the crossover integration with the satellite speakers, but not a high-pass filter to avoid exciting room modes!

Again, it would be quite disappointing for such an expensive sub. It seems the KH805 have also this option! Are you sure it's not the function of the band pass filter that you can manage on the PMC Sub1?

I can only repeat what I said earlier: a monitoring system is supposed to provide a reliable, consistent reference. If you have to change the level of the sub 'to suit your taste' something is very wrong with the monitoring as a whole. It's either balanced and right... or it's not!

Maybe I didn't explain this better. I meant that in this way you can choose how much sub frequencies to mix into the room (and then keep it constant of course). Sometimes when I hear a monitor speakers in a demo room I think that the speaker could be perfect if only it has a tad more sub power....other times I think the opposite. The advantage of a sub is that in this way I can make sound the monitor system in the way my personal preference go....and then of course keep it constant to familarize with the system and other references. It's like having once more EQ control back on the speakers. Because if - for example- I'd push the low end eq on the back of the KH310A, I would probaby enhance also 100Hz or higher, not just the sub stuff. Like having 4 EQ controls on the system, instead of three....

For what it's worth, given the option of the twotwo6/sub 1 or KH310 (amongst a few other high-end monitor systems) , I chose the latter and I have no regrets. And I don't envisage any need to add a sub to the system, either. I'm a fan of PMC generally and the twotwo6 is a great monitor, but I felt for mastering and quality assurance monitoring the KH310s were a better choice for me -- although I don't work with EDM; it's nearly all classical/acoustic stuff. However, I do have a TLE1 sub (the previous analogue model to the Sub 1) which I use for the LFE role with my big PMC system, and it is a very good and versatile sub...

I know you bought them and I really trust your reviews! I know you could probably buy whichever speakers you want with very good price but chosed them. So...this decision speeak for itself! Also these monitors got praised on many other magazines! So I'm very tempted to buy them! But I also know you work with totally different styles than me, and this is actually my main doubt...since in the demo room (with a quick comparation) I didn't find the KH310 to be all this different from the KH120A. They seemed to give more or less the same bass output. Probably the KH310 gave deeper low end information, while the KH120 had more power near the resonant cutoff frequency and this create an illusion of a similar bass power....but probably mixing on them is another story

[iasomph]

And most Genelec subs only give 90 degree steps... I'm not sure you'd notice much practical difference, to be honest.

Great, I thought it was a very important point in order to get a perfect time alignment between the sub and the satellites.

Yes... but the Sub1 is designed to be usable with several different monitors, and it's very easy to include options in the software. The KH is designed to be used with a very specific set of monitors, so it's going to work just fine!

In case I'll end up deciding to try a sub with the KH120A (or even KH310A) would you suggest the PMC Sub1 or the cheaper KH805? The PMC is more expensive (more than 2x so I expect better sound quality!) but the KH805 - ported - is designed to work specifically with their satellites. Which one would you suggest for my EDM needs?

It comes down to the room acoustics again. Often, where there are problems with room modes, one sub can't provide a completely flat response in room, and a second one is necessary to help 'fill in' the gaps! It's a very common solution.

Yes, but two subs would take too much space! Also, the room is not big and working all inside the box I will not move around the room a lot. The listening position will be where it will be, so I need the sound to be good in that position. I don't have clients coming to my studio and also the Sonarwors reference plugin will be optimized for the sound in my listening position...

[iasomph]

Hi Red Bladder, thanks for your reply.

3. Yes, it's called an on/off switch!

Yes but I'd want it to be activated/disabled remotely while sitting at the mixing position with a push of a button...

4. Either with an EQ or a sophisticated controller - though my advice would be to leave it alone.

why? Please explain, I want to investigate this better

6. Given that you imply having room problems and are unsure about speaker configurations, mastering is something you should be thinking about after another decade or two of experience and in a nice, large room that does not give you hot-spots.

I imply that my room will have problems because it's not so big and because it's not a custom built studio. I hope that with acoustic treatment I can get a decent sound room after all.

As for mastering, I think there's always a starting point somewhere. Of course I will not aim to master U2 tracks! But maybe some EDM guys that want to have tracks mastered with extremely good price with a very good reference listening system can be interested in this kind of service.

I know some friends of mine that has far less good monitoring system (and not acoustic treatment at all) that offer similar mastering services....and they got quite a lot of work! Of course only the market will tell if my offer will be good enough or not!
I don't see anything to lose here honestly. For first customers one idea could be to offer them free trial and they will purchase the masters only if happy with the result.

[Hugh Robjohns]

I've already planned about 2.500€ budget for acoustic treatment with GIK. They are very good guys.

Good plan, and they are indeed.

Sure. So you think the KH805, costing only 1.500€(half of 2.500£ you suggested) is too cheap to achieve optimal results?

I've not heard the KH805, but my understanding is that mechanically and acoustically it's the same as the KH810, just with simpler bass management and control facilities. Neumann aren't going to sell a badly designed subwoofer, so I'm sure it will do the job well.

Which are these tools?

Proper acoustic analysis tools...

KH805 is ported, while KH310A are sealed. Would you use them in conjunction?

Yep. They're designed to work together. Porting is not a 'bad thing'... Most high-end professional monitors are ported. Bad cabinet design, where the port is abused to make small, cheap speakers deliver far more bass than is sensible, is a bad thing.

I'm a little surprised that on a 3.600€ sub you can't do this!

It goes back to my earlier point: why would you want to? Either you have a properly working and balanced monitor system, or you don't. Would you want a switch to turn the tweeters off?

However sometimes you may want a more relaxed sound (without all that much lowend)...

Not me. I want it to sound right all the time.

... or you want to concentrate more on the midrange...

Are you saying the low end is masking the midrange and preventing you from hearing what's going on there? That suggests a poor bass unit putting out unhelpful harmonic distortion, doesn't it?

Also, despite the isolation works, disabling the subs could be good for mixing and producing at evening I think.

So where's the consistency in your reference monitoring?

I've never succeded in find headphones useful for judging sub frequencies. I always end up turning up the listening levels too much and getting ear fatigue earlier.

It's a case of ear-training. If you want the visceral feel of bass, look into the sub-pac devices to use with headphones (discussed elsewhere in the forums recently).

I meant that in this way you can choose how much sub frequencies to mix into the room (and then keep it constant of course).

Pretty much all subs have a volume or sensitivity control to allow level matching through the cross-over region during the installation setup.

H

[iasomph]

It goes back to my earlier point: why would you want to? Either you have a properly working and balanced monitor system, or you don't. Would you want a switch to turn the tweeters off?

Are you saying the low end is masking the midrange and preventing you from hearing what's going on there? That suggests a poor bass unit putting out unhelpful harmonic distortion, doesn't it?

Well, probably you are right for mixing, but for composing at evening without disturbing neighbours could be useful. Also, even if the room will not be able to manage perfectly the sub bass response, at least I can engage the sub occasionally to concentrate / compare against references just in relation to sub frequencies! And for the rest using just the satellite and avoid most of the room modes in the room and obtain in this way the best of both world. Sure, consistency would be a little compromised, but at least I can compare against good references my material and hear the sub...instead of having to crank up insanely the KH120A trying to hear the Sub frequencies more...

It's a case of ear-training. If you want the visceral feel of bass, look into the sub-pac devices to use with headphones (discussed elsewhere in the forums recently).

I hope you'll review the Subpac on SOS one day! I already wanted to pull the trigger on it, but the S2 has been out since more than one and half year. I personally think they may upgrade the product quite soon and so decided to wait for the S3 version. They upgraded from S1 to S2 version in about one year...so I think it will not pass too much time before they upgrade their product again!

Pretty much all subs have a volume or sensitivity control to allow level matching through the cross-over region during the installation setup.

True...this is why I started to think about using a subs in general instead than a full range monitos. for the extra flexibility. But it's just a question I'm doing to myself! I've not absolutely decided to give up on the KH310A yet. At the end of the day...I can still integrate the KH805 later on the KH310A in case.

There will be a noticeable quality difference in using KH310A + KH805 VS KH120A + KH805? I mean...once the low end driver is free from most of his works, there would be still a benefit of using the KH310A vs KH120A or the extra money don't justify the cost in such scenario?

[DC-Choppah]

In the Hi-Fi world, the advantage of subs are is that your main speakers don't have to try to reproduce the low end sounds which drive them in to a non-linear regime where distortion occurs. The cone doesn't have to move as far.

So when I auditioned my last sub for my stereo, what I listened for was how the sub made the B&W speakers sound better. Sure the sub also added the bass in properly but the real improvement was that the B&Ws no longer had to try and make the low end sounds so stayed in their linear region. So the mids sounded better.

You have to set things up so that sub filters the signal first and then passes on filtered (no low end) signal to your main speakers. So its the filters that are key for the advantage on your main speakers. The improvement in the mids is what you are after, along with the bass if that was missing for your speakers too.

So think of it as another 'way'. If you have two way speakers, then the sub makes your system 3 way.

[Jack Ruston]

Reading through all this, my instinct is that you're pinning your hopes on an easy (but perhaps costly) fix to a really thorny problem - We've all done it, I'm not trying to be critical. But you're hoping that by buying a quality sub you can solve the problem that you can't clearly hear what's happening in the low end. But the reality is that unless you can sort the room out to a very great extent, you never will, and that's a really difficult thing to achieve. It's easy to improve a room usually, and sometimes it's easy to improve it quite a lot, but to acoustically treat a domestic space to the point where it's worth dropping thousands of euros on a sub is not trivial. Sometimes you just get lucky and the room is already really pretty decent, but when it isn't...

I think you should allocate a small budget to getting someone in to measure this with you and see what's really happening acoustically before you do anything else. In the final analysis a smaller domestic space will usually be best served by accepting some compromise in ultimate low end reproduction in order to avoid over-exciting the room in tricky areas. If I had 5k to spend I'd be thinking that it was going to be split about half and half between acoustics and speakers and I'd be looking at smaller 3 ways, 2 ways, sealed boxes and perhaps a really good pair of headphones, like Audeze LCD-X's or something.

J

[iasomph]

"Jack Ruston"]Reading through all this, my instinct is that you're pinning your hopes on an easy (but perhaps costly) fix to a really thorny problem - We've all done it, I'm not trying to be critical. But you're hoping that by buying a quality sub you can solve the problem that you can't clearly hear what's happening in the low end. But the reality is that unless you can sort the room out to a very great extent, you never will, and that's a really difficult thing to achieve. It's easy to improve a room usually, and sometimes it's easy to improve it quite a lot, but to acoustically treat a domestic space to the point where it's worth dropping thousands of euros on a sub is not trivial. Sometimes you just get lucky and the room is already really pretty decent, but when it isn't...

Hi Jack, thanks again for your time! Yes, my real hopes is that the GIK treatment will solve the most relevant problems...anyway this is the first time I'm going to make an acoustic treatment plan, so I don't really know how much the room can improve actually in real life! Since this is the first time I will work in an acoustically treated room, I also hope this would make working there better compared with my current room that is completely untreated. Yes, of course I also hope that better monitors and/or subwoofer can also help me a little in this regard!

I think you should allocate a small budget to getting someone in to measure this with you and see what's really happening acoustically before you do anything else. In the final analysis a smaller domestic space will usually be best served by accepting some compromise in ultimate low end reproduction in order to avoid over-exciting the room in tricky areas.

I asked GIK if it was possible to have them to come in my place , but they told me that they work only remotely. Anyway I have a plant of my room, some pictures and also took REW measurements in the two possible listening spot (actually this is another though decision for me: choosing the best listening position, since these two listening spots are very different and each has his own strenghts and weaknesses).

You think taking personally REW measurements can be enough or it's better if I find someone more expert than me than come to my place and take these or other more specific measurements?

Also, you think I can get some useful help/advices if I post plants, photos and REW measurements here (maybe in the Studio Design section of the forum) ? It would be amazing and it would maybe also help in regard of which possible monitor size / type can suit my room best?

If I had 5k to spend I'd be thinking that it was going to be split about half and half between acoustics and speakers and I'd be looking at smaller 3 ways, 2 ways, sealed boxes and perhaps a really good pair of headphones, like Audeze LCD-X's or something.

Yes, this is why I initially tought about spending 2.000-2.500€ with GIK and 3.200€ on KH310A ! Then I've read wonderful things about the Amphions, and also got this special discount on PMC brand.....so many options and possibilites arised! Also the sub possibilities arised (that actually would probably be the cheapest option with just 1.500€). You know, when you spend so much money on a new monitoring system you want (and hope!) to do the best choice and not regret it! So I started exploring all these options, and indeed, it's a quite complicated and complex choice!

About Headphones: at Sonarworks says that HD650 are among the best...and I trust them because when I apply the correction curve, the difference is not night and day (like actually it is with other headphones I've tried). Of course I also know the LCD-X are stellar headphones, with a different technology....so it could be worth trying them out!

I actually dont love too much headphones in general (I prefer to use them for some specific task) because I tend to turn their volume up as working and because they don't give me that phisycal "oohhmph" that you get with speakers - even the little KH120A - while composing grooves and dance music.

[Hugh Robjohns]

It has been pointed out to me by a nice man at Neumann that integrating the KH805 sub with the KH120s allows the KH120s to sound better and go louder, thanks to a reduction in the workload of the KH120 bass driver. The KH310s goes deeper and has less midrange distortion than the KH120s, but adding the KH805 to that system brings about the same benefits of deeper bass, more SPL, and makes them "sound better".

He also tells me that the ported/sealed cabinet debate is not terribly relevant for the subwoofer as the porting only has effect below about 25 Hz, and the group delay increase happens at such low frequencies that is not perceptually important.

Apart from size and cost, there is only one acoustical disadvantage to adding a bass-managed (ie, a system which high-pass filters the satellite signal) subwoofer to the KH 120 or KH 310: it increases the group delay around the crossover frequency. This is evident in the measurements provided on the Neumann website – unlike most speaker manufacturers, Neumann put all their data and test measurements online.

The alternative configuration of running the main loudspeakers full range and allowing the subwoofer to take over below without high-pass filtering the satellites avoids this group-delay issue. However, it doesn't allow the satellite loudspeakers to play cleaner or louder because the bass driver is still working as hard as ever.

Clearly, there is no free lunch here, just different compromises. Neumann only offers the bass-managed option because although it costs more they believe it is a better way to do it. The simpler approach of just 'sliding' a subwoofer under the main speakers, they believe, brings more disadvantages than advantages and so don't offer or recommend this solution.

H

[John Willett]

Someone's been talking to Andrew Goldberg

But he does know his stuff.

[James Perrett]

My thoughts are that when spending this much money I would want to get a decent acoustic consultant involved who can come and look at your studio. There are probably details about your studio construction that may be important for a good acoustic design yet will be missed by a non expert. As I understand it, GIK only sell a limited range of acoustic treatments and there may be other choices that are more effective in your particular case.

[iasomph]

Hugh, thanks for sharing this, this is indeed an useful piece of information!

I also agree that a bass management option would be better than laying the sub under the monitors full range. The increased group delay would be at 80hz (crossover point), right?

What does this imply, exactly? some time smearing of these frequencies?

[Hugh Robjohns]

I also agree that a bass management option would be better than laying the sub under the monitors full range.

It really depends on the satellite monitors and what you're trying to achieve. There are pros and cons to both approaches, as mentioned. For example, if you don't want or need additional SPL, and if the LF/midrange distortion levels are already very good, then maybe high-pass filtering the satellites is unnecessary...

The increased group delay would be at 80hz (crossover point), right?

Yep.

What does this imply, exactly? some time smearing of these frequencies?

Essentially, yes. The LF appears to come from further away than the HF because of the additional phase shifts introduced by the high-pass filtering. It's a pretty subtle effect, though, to be fair, and something most manufacturers are content to live with on the basis that the benefits outweigh the disadvantages!

It's worth noting that this group delay issue is much easier to correct when working with digital filtering (like PMC's twotwo speakers) than with analogue designs... but then digital filtering brings other sound quality aspects into consideration... It's all swings and roundabouts.

H

[iasomph]

Hi James,

thanks for sharing your point of view. An acoustic consultant would be nice to have (as always:). However, to make things more clear, this room will not be only a dedicated studio room. The room will also be used as a secondary bedroom, so there will be a bed in the room (As well as some small necessary furnitures like a small closet for some clothes).

This just to say that I cannot make structural changes to the shape of the room, adding or removing walls, etc.... I can only improve the room adding non destructive things like acoustic panels, bass traps, deciding optimizing the listening position at its best, choosing the best monitors and similar things like this.

You think an acoustic consultant "on place" could be still useful in this case? If yes, how much would it cost (approximatively of course) for helping me in sorting out these things?

As far as panels go, GIK seems a great choice for many reasons: last but not least because they have a great attention to the "healthy" side of panels. Since this room is also a bedroom and I will spend a lot of time inside, this is one aspect I really care about! Then their products are described on forums as very good for their price. And I have to say they offer great support via e-mail and never try to push you to buy unnecessary panels. Liked my experience so far...and I hope I'll be happy with the ending acoustic result, of course

Of course I can also integrate other brand products in the room if it's necessary/better. I've taken a look at the the PSI AVAA intelligent bass traps....quite effective and small...but at what sort of price!!! More than the KH310 for just two of them :/

[iasomph]

Hugh,

thanks for the clarifications! what are the disadvantages of the digital approach (like PMC TwoTwo) in this regard, instead?

Also, I thought about another thing: I've noticed many people recomend two subwoofers in the room instead of one for obtaining a more linear and effective result against room modes. It seems this would be a benefit especially in small rooms. But using two full range monitors like KH-310As would not be a very similar concept in this regard, in the end? Because also in this case there would be two different speakers that take care of the low frequencies separately...

[Hugh Robjohns]

what are the disadvantages of the digital approach (like PMC TwoTwo) in this regard, instead?

Some people don't like the idea of all the extra A-D and D-A conversions and digital processing involved...

...using two full range monitors like KH-310As would not be a very similar concept in this regard, in the end? Because also in this case there would be two different speakers that take care of the low frequencies separately...

The problem with this approach is that you can't position the bass drivers to optimise their acoustic input into the room in respect of room mode nulls. The positions of one or more subwoofer(s) can be optimised for that without affecting the stereo image. That's much harder -- if not outright impossible -- to achieve with range speakers.

So, if you're relying entirely on full range speakers you really do have to get the room modes thoroughly sorted out. If you're using satellites and subs you have a little more leeway to work around some room mode issues.

H

[iasomph]

Clear explanation, thanks!

But positioning two subwoofer in different spots in the room don't create problems with timing and phase?

Let's say one subwoofer is placed 40cm behind the satellites (but still in front of me), while the other other subwoofer, in order to "cure" the room modes properly, is placed 1.5 metres away from me (and behind me).

How to configure effectively this setup? The lows from the second subwoofer will arrive at my ears later...so I need to add a delay to the satellites and to the first subwoofer accordingly? I suppose I will need to add a delay processor to the chain at this point to obtain a correct timing from the whole system.

The digital processing of the PMC, for example, would take care of all this process digitally and so automatically?

And also: the KH805 sub have a crossover at 80hz. This imply that all frequencies under 80hz are treated as mono frequencies in this way, because processed only by the sub... right? Could this be another problem of using a sub? I know it's usually better to have low frequencies mixed in mono...but 80hz is not really THAT low and could be worth having the chance to listen to them also in stereo if needed. I think many recordings have some stereo information at 80hz and I would completely lose this information in this way...don't I ?

curious to know how complicated positioning and using subs can be...

[Hugh Robjohns]

But positioning two subwoofer in different spots in the room don't create problems with timing and phase?

Not if they are each set up correctly, with the correct phase alignment for their respective positions relative to the main speakers. All you're aiming for is the LF from each of the satellites and each subwoofer to arrive in phase at the listening position through the crossover region. And remember... Subwoofers don't do transients, just rumbles!

... all frequencies under 80hz are treated as mono frequencies in this way, because processed only by the sub... right? Could this be another problem of using a sub?

No. We can't detect the direction of low frequencies in a room because of room boundary reflections. Provided the crossover is below about 90Hz (and the sub doesnt generate audible harmonic distortion) you won't know where it is.

.,,curious to know how complicated positioning and using subs can be...

Yes. Certainly not a trivial easy fix, and potentially capable of mre harm than good. I think this is where I came in...

H

[iasomph]

Not if they are each set up correctly, with the correct phase alignment for their respective positions relative to the main speakers. All you're aiming for is the LF from each of the satellites and each subwoofer to arrive in phase at the listening position through the crossover region. And remember... Subwoofers don't do transients, just rumbles!

So, a very variable phase control seem to very useful then. I've read review of the Avalanche subwoofer from Unity Audio and - while very good in quality - it seems it only has a 180° phase switch. This doesn't seem to be ideal for perfectly match the phase with the satellites and the other possible sub in more complicated positioning situations....

Yes. Certainly not a trivial easy fix, and potentially capable of mre harm than good. I think this is where I came in...

Hmmm....PMC Sub1 digital integration with their satellites solve most of these positioning problems related with phase? Would allow a non expert in subs like me to obtain the best out of it, compared to setting up a "traditonal" sub?