SubZero transformer DI boxes

[Sam Spoons]

Has anybody used these? They came up on another thread recently partly for being super cheap. I need a couple of extra DIs and wondered if these were worth a punt (I have used Behringer DI120s in the past and they are truly dreadful)?

[MarkOne]

Indeed the DI120 is possibly the worst bit of audio gear ever made! (The Ultra DI100 is actually much better and actually usable.

Not tried the SubZero unit but have a look at these:

Lambden Audio from StudioSpares. Actually pretty reasonable.

I've added one to my keyboard pedalboard/connection rig and certainly for the average pub gig its more than fine.

Would it compare well to a Radial ProDI? Probably not, but at the moment they're £20 and I think worth every penny.

[Sam Spoons]

Thanks Mark, I want single channel DI's just now but will save those for later.

[The Elf]

Some things are worth spending a bit more money on, and DIs are defintiely in that category for me. These days I'd head straight to Orchid, but the Radial J48 was a revelation, especially on bass guitar.

[MarkOne]

I don't disagree, and if I needed a DI for use in the studio, to DI a bass for a recording, then I would go and acquire a good-un.

But in the context of offering up a balanced signal to a FOH in an average pub (Or just plumbing it in to our own PA with it's aging Mackie mains), I stand by that Lambden unit as being an adequate* and cost effective unit, to get my mediocre keyboard chops out to the punters

*Actually last summer I did a multitrack of one of our gigs off the Zoom L20R, and I was pretty happy with the keyboard sound when I got the tracks back home and loaded into the DAW

[sonics]

You don't say what you want the DI boxes for, which has a bearing on recommendations.

(I have used Behringer DI120s in the past and they are truly dreadful)

You don't say anything about why?

FWIW, I've used three models of cheap Behringer DI box at line level and all worked fine for me...but I use mostly Radial for my pro gigs. I see the SubZero DIs start at 15 pounds. How do they make any money?

[Sam Spoons]

They'll get used for keyboards in my home studio and also as isolators where necessary on the odd gig I still do. I already have 6 x Orchid DI's (one Classic and 5 x Micros) so I'm looking for something different to complement them.

[James Perrett]

FWIW, I've used three models of cheap Behringer DI box at line level and all worked fine for me...

But have you used a DI120? By all accounts they are somewhat "special".

[Drew Stephenson]

A soundie plugged me into one in Leeds at one of my last gigs before the pandemic. The fizz was horrible. I swapped it out for one of my Orchids when he wasn't looking and all was good.

[sonics]

But have you used a DI120? By all accounts they are somewhat "special".

I had one about 20 years ago but it seems to have walked. Maybe that's a good thing?

[Dan LB]

I'm looking for something different to complement them.

Why? You’re not going to find anything desirable in a 15 quid DI. Just get some more Orchids. They’re cheap enough!

[Sam Spoons]

I almost agree with you but Orchid kit is much more expensive since they handed distribution over to Showbitz, (Micro DI has gone from £28 to £43, Classic nearly doubled from £36 to £68) still not expensive but less of an impulse buy price. And I want transformer DIs which Orchid don't do.

[The Elf]

You don't say what you want the DI boxes for, which has a bearing on recommendations.

(I have used Behringer DI120s in the past and they are truly dreadful)

You don't say anything about why?

I can't speak for Sam, but a local studio has a whole cupboard full of these. The noisest (hum AND hiss) trash of any DI I've had the misfortune to use. I'd happily bin the lot, but these days I just quietly put them back in the cupboard when I'm working there and use my own.

[Hugh Robjohns]

The DI120 does not employ isolation/step-down transformers. And its ground-lift arrangement is unusual — similar to a pseudo-balanced approach. The active elements are TL064s... not the quietest op-amps on the block.

[Dan LB]

I almost agree with you but Orchid kit is much more expensive since they handed distribution over to Showbitz, (Micro DI has gone from £28 to £43, Classic nearly doubled from £36 to £68) still not expensive but less of an impulse buy price. And I want transformer DIs which Orchid don't do.

Ah! I didn’t realise there had been such a price hike. It’s been many years since I bought my Micros. Also, fair point about the transformers.

What about the ART Zdirect? https://artproaudio.com/product/zdirect ... irect-box/

You can also get a dual channel version which is even more value for money.

[ef37a]

The DI120 does not employ isolation/step-down transformers. And its ground-lift arrangement is unusual — similar to a pseudo-balanced approach. The active elements are TL064s... not the quietest op-amps on the block.

DI20_Schematic.jpg

What a faff way to make a DI box! Yes the TL64 is more a 'cooking' IC than 'studio' but putting 200k in the op amp's inputs is 8uV of noise they could have avoided!

Passive DIs are pretty simple devices and since Orchid have gone a bit pricey why not make your own? Spend the big money on a decent transformer (Sowter if you want home grown) then its just a tin and some jacks. Or you could use a really cheap and grotty traff and get some "attitude"?

BTW Hugh, how do you get Behringer schematics please? If I could find one for my BCA2000 I would get it out of the loft and try to fix it!

Dave.

[Sam Spoons]

Passive DIs are pretty simple devices and since Orchid have gone a bit pricey why not make your own? Spend the big money on a decent transformer (Sowter if you want home grown) then its just a tin and some jacks. Or you could use a really cheap and grotty traff and get some "attitude"?
Dave.

Yup, well within my skill set, but if I want attitude, or to only work at modest signal levels, those SubZero boxes make DIY pointless.

If I wanted good I would consider making my own Dave, but would probably spend the money and buy some decent ones, DIY won't have any resale value, Radial will and probably won't cost that much more than I could buy the bits for.

The DI120s were noisy and physically extremely fragile, certainly not up to being kicked around a live stage, Orchids will still be used by our cockroach masters after the apocalypse

[ef37a]

Passive DIs are pretty simple devices and since Orchid have gone a bit pricey why not make your own? Spend the big money on a decent transformer (Sowter if you want home grown) then its just a tin and some jacks. Or you could use a really cheap and grotty traff and get some "attitude"?
Dave.

Yup, well within my skill set, but if I want attitude, or to only work at modest signal levels, those SubZero boxes make DIY pointless.

If I wanted good I would consider making my own Dave, but would probably spend the money and buy some decent ones, DIY won't have any resale value, Radial will and probably won't cost that much more than I could buy the bits for.

The DI120s were noisy and physically extremely fragile, certainly not up to being kicked around a live stage, Orchids will still be used by our cockroach masters after the apocalypse

All very good points Sam. I have found a Monacor 1:10 transformer mod# DIB-110 with a good specification, will handle +18dBu it seems and they are a fair price of £16.00. As yet I cannot seem to find anyone who will sell me one but as soon as I shall get one and knock up a box.

Dave.

[Hugh Robjohns]

BTW Hugh, how do you get Behringer schematics please?

I found that one on a public website, but I've no idea where it came from I'm afraid. I doubt Behringer are happy its out there, either!

[Hugh Robjohns]

The DI120s were noisy and physically extremely fragile, certainly not up to being kicked around a live stage

I'm not convinced the DI120 was really conceived as a true DI box at all, for the following reasons:

1. It doesn't inherently pad the output signal down to mic level.

2. It has (crude) balanced inputs.

3. It has a Split feature to duplicate one input at both outputs.

4. It doesn't provide galvanic isolation.

I think it was conceived as a balanced line driver/signal splitter and was re-purposed somewhere along the line.

[sonics]

Just for giggles I opened up a Behringer DI400P I have here. It could't be farther from the DI20. It consists of linked input and parallel sockets, a single transformer, ground lift switch and output XLR. No other components al all. At least it doesn't hiss...

Further details from the official blurb include:
"Ultra-flat frequency response due to renowned BEHRINGER OT-2 transformer"
and
"Allows direct connection to speaker outputs with up to 3,000 Watts"

I bought two to run an outdoors film screening to balance the music source outputs. They worked just fine. I stress that the store I had to use had no other DI boxes for sale!

[sonics]

Just for giggles I opened up a Behringer DI400P I have here.

Just in case you wish to see...


I hope you're all slack-jawed and gasping in admiration at the "renowned Behringer OT-2"!

[James Perrett]

That's looking remarkably similar to the Whirlwind IMP2.

https://www.youtube.com/watch?app=desktop&v=SZ2gmUGGvCM

has an internal shot halfway through.

[Hugh Robjohns]

[ef37a]

Just for giggles I opened up a Behringer DI400P I have here.

Just in case you wish to see...


I hope you're all slack-jawed and gasping in admiration at the "renowned Behringer OT-2"!

To be slightly fair to whoever made that box, it is quite hard to make a tidy job with transformer wires (and why are they always so stiff?) and at least they put a blob of red Loctite on the transformer nuts!
The transformer is also bigger than I would have guessed.

Dave.