Can resistors affect the tone in audio devices?

[John 11]

Hello,
I have a question. I read somewhere preamps can produce a specific tone, which is obvious due to its internal construction (e.g. a tube preamp microphone can produce a warm tone).

I am not an engineer, and I have never ever considered that, but does it mean if I used a tube condenser microphone connected to the audio interface (e.g. Focusrite Clarett) with a transistor preamp microphone, I would lost this warm color tone quality of my mic, because the preamp is simply transistor?
If not, please let me understand why. I guess, I can miss something there.

The another question is related to knobs/resistors in audio devices:
According to this, preamps can produce a specific tone when using a knob to achieve this. Does it mean, e.g. audio compressors, that have knobs for GR ratio, attack, release, makeup gain and so on, can also provide a specific tone, as they can work using a transistor/tube? (comparing it to preamps that also use knob/resistor to control output level).

I am trying to figure out if all potentiometers on such audio devices can provide a specific tone because of its internal equipment. For example, if a vintage compressor using a tube have all potentiometers that use it in this setup to control audio signal regarding the time (attack/release), GR, and they can produce the specific tone (all these knobs). I heard many times a vintage compressor can produce a warm tone, but never considered that regarding all knobs.
 
I would be grateful for your help.

[Tomás Mulcahy]

The short answer is no. But it depends. Before launching in to an explanation, can I ask you to try to specifically define or describe what you mean by tone? So I can better attempt to put an answer in context for you.

Also remember what Hugh advised you already:

...you're going to have to work through electronics fundamentals and on into their advanced applications.

You need to do a course.

[ef37a]

Physical resistors are very linear that is the current through them is almost exactly proportional to the applied voltage over a wide range of voltages*.
But "very linear" does not mean perfectly linear! Some resistors in some circuits produce measurable distortion. However, the supply voltages in small signal transistor and op amp circuits are so low, usually less than 36V DC that I doubt any distortion could be measured even with the best equipment?

Even in a valve capacitor microphone this should not be a problem. Yes, the HT could be 200V+ but the actual signal voltage only a tiny fraction of that. I would suggest that most of the claimed "warmf" comes from the transformer if there is one or in the mind of the user! I would be more concerned about the CAPACITORS used! But not in mics, again signals normally too low.

*Where you have very high voltages, 450+ and large signal voltages e.g. valve power amplifiers the old Carbon composition resistors did produce a tiny amount of distortion but since they also hiss like a viper who in their right mind would use them today?
I was told that a guitar company (no! NOT that one) charged the lab to build two 'identical' power amps. One with Ccomps and one with Metal Films. On an A/B test no one could tell them apart!

Dave.

[John 11]

The short answer is no. But it depends. Before launching in to an explanation, can I ask you to try to specifically define or describe what you mean by tone? So I can better attempt to put an answer in context for you.

Also remember what Hugh advised you already:

...you're going to have to work through electronics fundamentals and on into their advanced applications.

You need to do a course.

I don't need a course, and any judgment. If I knew I need one, I would do it. I need a simple answer, which is why I believe this forum is created to help understand some things, instead of sending folks to do a course.

The tone described in my topic was related to tube/transistor preamps.
I have read, in example of tube preamp, that it can provide a warm tone, when a transistor preamp can produce different sonic quality. There is nothing special to describe in terms of 'tone'. It's about the internal components and what kind of sonic quality they can produce.
This is why, I asked if I used a tube condenser microphone connected to transistor preamp I would loose this 'warm' tube quality of mic that can provide by using the transistor preamp mic.
And another question was related to knobs/resistors in compressors, if ones working with tube/transistor can produce a specific tone, as the preamps do.

[James Perrett]

One thing I would say is to ignore most of what you read or watch on the Internet. In my experience, genuinely old gear can actually sound colder and more "digital" than newer gear. Gear that sounds different is usually deliberately designed to be that way - the original Neumann U87 is one example where the transistor version sounds "warmer" than the valve version (the U67) or the later version (the U87ai) because Neumann designed it that way. Similarly, my transistor U47 sounds slightly warmer than the valve version that I compared it to a few years ago.

I think Dave has pretty much covered the differences due to resistors. At audio frequencies, and with typical audio levels, they make very little difference. You need to choose them more carefully at radio frequencies where their inductance may become a factor or at low levels where noise is more important.

[Tim Gillett]

...does it mean if I used a tube condenser microphone connected to the audio interface (e.g. Focusrite Clarett) with a transistor preamp microphone, I would lost this warm color tone quality of my mic, because the preamp is simply transistor?...

The same sort of thing can be said of feeding an analog recording into a digital recorder. "All the warmth gets sucked out", some people claim. No, because with the digital recording, "what goes in is what comes out" all the warmth or lack or warmth is preserved, as we should expect.

Many people cant recognize in a recording an accurate, and therefore an inaccurate representation of a human voice. I suggest you first learn listening skills, to recognize "fidelity", say fidelity to the human voice. Recognize the sound of a real human voice, listening face to face. Then having learned to recognize such "true to life" fidelity, progress onto recognizing different ways of changing the sound. Without a benchmark, we are just floundering. In the end it's all about the sound.

[James Perrett]

I don't need a course, and any judgment. If I knew I need one, I would do it. I need a simple answer, which is why I believe this forum is created to help understand some things, instead of sending folks to do a course.

There are no simple answers in electronics. The more I get into the subject the more I realise how much more there is to know - and I've been doing it both as a hobby and professionally for over 50 years. I still get plenty of "I hadn't thought of it like that" moments when talking to people whose expertise lies in different areas to mine.

[Hugh Robjohns]

I need a simple answer, which is why I believe this forum is created to help understand some things, instead of sending folks to do a course.

There are few 'simple answers' in audio electronics because there are too many different contexts and nuances, and to understand them you need an understanding of electronics to be able to distinguish between the nonsense you've been reading and the real truth. Hence the suggestion that learning about audio electronics — either by self-learning from books, or a course — would be helpful to you and your current interests in audio technology.

Preamps, and other audio devices, can have a recognisable sound character or tone, but its through design and circuit topology rather than specific components.

I have read, in example of tube preamp, that it can provide a warm tone, when a transistor preamp can produce different sonic quality.

You can certainly find examples with those properties, but I could just as easily point you at a valve preamp that isn't 'warm' at all, and a transistor preamp that is very 'warm'.

It's a popular myth that everything with a valve in it sounds 'warm'... but it's utter nonsense!

This is why, I asked if I used a tube condenser microphone connected to transistor preamp I would loose this 'warm' tube quality...

No, it wouldn't... but much depends on the specific preamp and mic involved.

And another question was related to knobs/resistors in compressors, if ones working with tube/transistor can produce a specific tone, as the preamps do.

If you understood how compressors worked and what those 'knobs' are actually doing, you'd realise how daft that question is. ...but the 'simple answer' is no.

[ef37a]

Since engineers have been able to capture and amplify sound electronically they have very largely striven to make that amplification as 'perfect' as it can be.

That was difficult at first because all they had to work with was valves* and pretty poor ones at that. Valve technology improved as did audio transformer science and by I would say the mid 1950s valves were capable of very good quality reproduction indeed, in fact it took another couple of decades or so for transistors to catch up.
But catch up they did and for a very long time it has been possible to make a whole repro' chain up to power amplifier that is "subjectively perfect".

I was not there but I am convinced that the engineers at EMI and the Beeb say knew all was not perfect in the early days but did not 'excuse' it as something desirable! I have been on the edges of the hi fi world for 60 years and it seems to me that all this talk of "warmth" and "valve sound" is a very recent phenomenon?

*We will leave out Magnetic Amplifiers? (thinks) Of course the value of resistors is important. Take a simple low pass filter,if you halve the value of the series resistance you double the turnover frequency. One expects 'quality' audio kit to be made with close tolerance Cs and Rs but that is not always the case in the 'Ball of String, Stick of chalk' world of guitar amplification!

Dave.

[Exalted Wombat]

On an A/B test no one could tell them apart!

No-one can EVER tell 'tell them apart'. (When 'them' are competently-designed reasonably modern electronic devices intended to be linear.)

[ef37a]

On an A/B test no one could tell them apart!

No-one can EVER tell 'tell them apart'. (When 'them' are competently-designed reasonably modern electronic devices intended to be linear.)

I was not complete or clear there Womby. The CEO of the guitar Co was adamant that they must use the Carbon resistors (yes, necessary for RF J) "because of the tone" The engineers were not keen because they knew that CCs are noisy and prone to shift value over the years. They therefore built the two and and boss could not pick it out!

Dave.

[Folderol]

Having also worked in the days of carbon resistors, I was also delighted when metal oxide/film became cost effective.

[ef37a]

Having also worked in the days of carbon resistors, I was also delighted when metal oxide/film became cost effective.

Have you ever tried to destroy one Will? I was given the job of putting a fault on am amp to test an interviewee and could not make a 10k 2W go O/C, at least not without burning it up, obvious fault. I had to resort to filing a gap in the track underneath the resistor (in the HT to the PI).

I also had a good old blow up of a KT88* in a 200 watter and the 10k 1/2W grid stopper was as black as yer hat. But it STILL read 10k to 5%!

*Modern 88s will not stand the original GEC spec!

Dave.

[Folderol]

Having also worked in the days of carbon resistors, I was also delighted when metal oxide/film became cost effective.

Have you ever tried to destroy one Will? I was given the job of putting a fault on am amp to test an interviewee and could not make a 10k 2W go O/C, at least not without burning it up, obvious fault. I had to resort to filing a gap in the track underneath the resistor (in the HT to the PI).

I also had a good old blow up of a KT88* in a 200 watter and the 10k 1/2W grid stopper was as black as yer hat. But it STILL read 10k to 5%!

*Modern 88s will not stand the original GEC spec!

Dave.

Never 'tried' to destroy one, but did come across one glowing bright red in a faulty inverter. When I switched off and let everything cool down I don't know if it was still the correct value - it was impossible to see what the value was, and there was a hole in the PCB where the printing would have been, so I didn't even know what the component number was!

Re: Modern valves.
I get the impression that none of them are as good as the old ones. Also a lot of them just don't seem to look right.

[resistorman]

RE your 3 questions: No, in all cases. Why are you so set against studying a subject you are interested in?

[Matt Houghton]

Seems to me that these points are worth repeating/highlighting...

Preamps, and other audio devices, can have a recognisable sound character or tone, but it's through design and circuit topology rather than specific components.

I could just as easily point you at a valve preamp that isn't 'warm' at all, and a transistor preamp that is very 'warm'.

...It's a popular myth that everything with a valve in it sounds 'warm'... but it's utter nonsense!

Might also be worth reading Hugh's longer article on the subject of Analogue Warmth.

As for capturing that sound with solid-state and digital gear, without sacrificing anything, yes, absolutely you can.

[John 11]

Preamps, and other audio devices, can have a recognisable sound character or tone, but its through design and circuit topology rather than specific components.

Thank you Hugh, and others that have responded to my questions - I appreciate it.
I think that was the missing point, which in my opinion didn't make any sense, that a simple knob of the preamp, compressors or other audio devices using a valve/transistors is prone to get any sonic quality, controlling the audio signal.
I am aware my questions could sound very weird and unconvincing, but I was just trying to find out, if it's true that preamps can produce a specific sound character and might affect the microphone that doesn't use the same sound characteristics, basing on the information I have simply found. Which is why I asked, feeling there something can be wrong.

Can I also ask you, why a tube condenser microphone wouldn't loose its sonic quality using for instance a solid-state preamp which has a different design and circuit topology than such a microphone? If preamps can produce a specific sound characteristic as it was said, why it doesn't affect the microphone sound? The only thing that crossed my mind for this complex question is two different audio devices don't have to deny each other, they simply work how they simply have been designed for without loosing the quality of both devices, but I don't know if it's sufficient explanation of this.

If my question is too complex and hard to explain, I could understand that.

Edited to fix quotes - JP

[James Perrett]

Basically, the differences in sound between different microphones are much greater than the differences in sound between different preamps. When used within their design limitations, most preamps will sound the same and be almost transparent. You only start to hear obvious differences when you push them towards their limits. Therefore most preamps will preserve the sound of the microphone - no matter what technology is used in the preamp.

[MarkOne]

I guess the answer is “it depends”

Warmth is distortion. Usually the soft clipping that takes place in a valve circuit or tape saturation yields even harmonic distortion, that augments the fundamental frequencies that is pleasing to the ear.

Hard clipping present in (some) transistor circuits create odd harmonics that sound unpleasant. (Usually) Though you can design circuits with transistors that add soft clipping.

If you have a mic that has been deliberately designed to create even harmonics when you drive it hard enough, it could sound ‘warm” put that through a preamp that is designed to be very linear to high levels it will neither add or take away any of that”warmth” A preamp that is designed to add even harmonics when driven hard will add more “warmth” but won’t take anything away from the original input. It’s just adding more distortion (which might still sound good, but might start to sound, well, bad. Putting the signal into a badly designed preamp that has a hard clipping characteristic, it will add a bunch of ugly distortion to the “nice” distortion and it will still sound ugly.

None of these scenarios really have much to do with valves, or transistors, but with the design intent of the circuit.

[Hugh Robjohns]

I was just trying to find out, if it's true that preamps can produce a specific sound character...

Yes they can — its one reason for picking one rather than another — but most only exhibit a sound character under very specific operation conditions. Most are essentially colourless in most applications.

...and might affect the microphone that doesn't use the same sound characteristics

Anything that adds colour to the source colours the source, regardless of the technology used. However, there's no inherent reason for anything to add colour if designed not to add colour.

Can I also ask you, why a tube condenser microphone wouldn't loose its sonic quality using for instance a solid-state preamp which has a different design and circuit topology than such a microphone?

A preamp can be designed to pass the signal without changing it using many different technologies — valve, solid-state or whatever. The technology is just a tool. Its how its put together that matters.

If preamps can produce a specific sound characteristic as it was said, why it doesn't affect the microphone sound?

If the preamp is designed to add colour then it will colour the sound from the mic. If it's not designed to add colour it won't.

If my question is too complex and hard to explain, I could understand that.

It's more a case that your question isn't derived from an underpinning knowledge – there is no solid foundation so it's like asking about algebra without understanding multiplication or division...

[Tomás Mulcahy]

I don't need a course, and any judgment. If I knew I need one, I would do it. I need a simple answer, which is why I believe this forum is created to help understand some things, instead of sending folks to do a course.

You claim you need a simple answer, yet you are clearly not satisfied with a simple answer, nor are you satisfied with the less than simple answers you already got. That's a circle I won't get involved in

[John 11]

Thank you all so much for your response. The example, when the preamp that exceeds its limit makes a sense in terms of transparency of the audio signal regardless the technology was used (it's rather difficult to imagine for me it on the another way, as MarkOne said, that there can be microphones that can introduce distortion itself towards the highly linear preamp that doesn't exceeds its limits - or I could misunderstand it. I am convinced distortion can be achieved when input signal exceeds its level above 0dBFS in a preamp, and not in the microphone itself according to this description - in this case it's impossible).

[John 11]

I don't need a course, and any judgment. If I knew I need one, I would do it. I need a simple answer, which is why I believe this forum is created to help understand some things, instead of sending folks to do a course.

You claim you need a simple answer, yet you are clearly not satisfied with a simple answer, nor are you satisfied with the less than simple answers you already got. That's a circle I won't get involved in

I didn't say, I am not satisfied. I have got many examples to understand it much more clearly and it helped me a lot. I would advise you to stop saying what someone can think, as you aren't a God.

[Wonks]

I don't need a course, and any judgment. If I knew I need one, I would do it. I need a simple answer, which is why I believe this forum is created to help understand some things, instead of sending folks to do a course.

You claim you need a simple answer, yet you are clearly not satisfied with a simple answer, nor are you satisfied with the less than simple answers you already got. That's a circle I won't get involved in

I didn't say, I am not satisfied. I have got many examples to understand it much more clearly and it helped me a lot. I would advise you to stop saying what someone can think, as you aren't a God.

And I'd suggest you think more about how you respond to people who know a lot more about it than you.

You simply come across to me as a troll.

[Tomás Mulcahy]

I didn't say, I am not satisfied.

You didn’t say it no. You did it. By rejecting the simple answer, and reframing the less simple ones with further fixed ideas. That’s why you appear to be trolling.