DIY transformer box to add color - Gearspace.com
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15th March 2009
#1
Lives for gear

🎧 10 years
DIY transformer box to add color

I heard an engineer talking about running tracks through a 1:1 transformer to add color to the sound. I think he said it was a Sowter that he took out of a broken Allen & Heath desk. After I did a search on google it seems that there might be a way of building a box with ins and outs, connected to the transformer that you can do this with, but I've found little more about it.

Can anyone tell me how I could wire something like this or give me schematics for it?

What might the results of doing something like this be sound-wise?
16th March 2009
#2
Louder Than Liftoff

🎧 15 years
Get yourself some 600:600 ohm transformers. You'll need to consult the datasheet from the manufacturer whose transformer you are using to know which colored wire is what. But you basically wire XLR connectors to the input and output of the transformer. Simple as that.

If it's a steel core transformer you will experience increasing low frequency distortion with level. If it's a nickel core then it will sound really clean and you probably won't notice much difference in sound.

16th March 2009 | Show parent
#3
Gear Nut

🎧 15 years
interested in this aswell, i got a clean preamp and lets say i want to add color to the sound im recording lets say vocals
so how does the connection goes?

Clean Preamp Output ---> DIY Colored Transfo Input

then

DIY Colored Transo Output ---> Interface (A/D, Soundcard, Mixer)

Correct? would it need powersupply or simply just wiring the xlr in and out adapters?

thanks
16th March 2009 | Show parent
#4
Lives for gear

🎧 15 years
Quote:
Originally Posted by tWoKp. ➡️
interested in this aswell, i got a clean preamp and lets say i want to add color to the sound im recording lets say vocals
so how does the connection goes?

Clean Preamp Output ---> DIY Colored Transfo Input

then

DIY Colored Transo Output ---> Interface (A/D, Soundcard, Mixer)

Correct? would it need powersupply or simply just wiring the xlr in and out adapters?

thanks
i think this could be a brilliant idea as well. could be incredibly easy to wire a few into a 1ru 'trafo color box' too. or at the least i've got a useless behr di-100 di box i could swap the di trafo out of and presto.

so hypothetically, if you were doing it with cinemags:
Line Input Transformer
Cinemag Audio Output Transformers

you'd take a CMLI-600/600C wired directly to the input jack, then hook that to a CMOL-2x600T2 wired to the output jack?

regarding 1:1 trafos, if they are 1:1, why is there any diff between input and output? or isn't there?

also, do 1:1's have less color/effect than bigger/smaller ratios?

and lastly, from an engineering standpoint, what's usually the point of 1:1 (600:600) trafos anyway? i understand they can be used as signal splitters. cinemags pdf's suggest that adding them to a signal chain will also cut hum. is this via their high cmrr?

thanks
16th March 2009 | Show parent
#5
Lives for gear

1 Review written
🎧 10 years
I think this is a great idea and cheap idea for all the ITB guys...
16th March 2009 | Show parent
#6
Gear Guru

🎧 15 years
This is a brilliant idea based on the hype of transformers on this very site.

But in practice, waste of time IMHO.

Keep in mind, I know nothing about making gear but…

This project would be the equivalent of putting a nice piece of analog gear into bypass.

And a lot of those great transformers are impossible to find. Pultec, LA2a, Neve 2254s.

So you'll be stuck with a high quality modern sounding transformer.

At about $65 a pop, and using both an input and an output transformer on each channel, we're talking about just over$2,000.00 for a 16 channel unit that Superman couldn't distinguish in a blind A/B test.

No?
16th March 2009 | Show parent
#7
Lives for gear

🎧 15 years
Quote:
Originally Posted by Kenny Gioia ➡️
This is a brilliant idea based on the hype of transformers on this very site.

But in practice, waste of time IMHO.

Keep in mind, I know nothing about making gear but…

This project would be the equivalent of putting a nice piece of analog gear into bypass.

And a lot of those great transformers are impossible to find. Pultec, LA2a, Neve 2254s.

So you'll be stuck with a high quality modern sounding transformer.

At about $65 a pop, and using both an input and an output transformer on each channel, we're talking about just over$2,000.00 for a 16 channel unit that Superman couldn't distinguish in a blind A/B test.

No?
that's the problem - getting good colored trafos these days...

regardless, i think the idea would be to just do 1 or 2 channels and throw them in after a bland pre-amp or other place where desired in a given OTB signal chain.

no, it wouldn't make sense to go otb just to hit a tranny due to d/a/d degradation, but if you're already out for something else it could be a handy option to chain in.

many high end summing buses get a large % of their sound from the trafos they do or do not use, so even with modern parts, transformers are not inconsequential in sound or character.

but ya, i guess no matter what you talk about there are always people who say it makes no difference. ie. no one i know can a/b a panasonic fm cap vs a xicon, but that doesn't mean they are equivalent.
16th March 2009 | Show parent
#8

🎧 10 years
Do you mean something like this?

Mixmasters Pro Audio

Cheers
16th March 2009 | Show parent
#9
Lives for gear

1 Review written
🎧 15 years
What about that 8 channel dohicky from ART? Probably for the price, the trannys might suck ( don't know for sure, haven't herd it....).But at least there's the casing/connectors, even if you need to swap out for better trannnys.. I think it's about $130.00'ish... 16th March 2009 | Show parent #10 Kush Audio 🎧 15 years Quote: Originally Posted by audiovisceral ➡️ many high end summing buses get a large % of their sound from the trafos they do or do not use... the sound comes from the entire output stage, which includes the trafo but is very much a sum total of the whole circuit around it. usually, the more toney boxes will also have some sort of custom op-amp(s) in there as well. gregory scott - ubk . 16th March 2009 | Show parent #11 Lives for gear 🎧 15 years the benefit you get from transformers are huge. i wouldn´t care about the ADDA, because you´re getting so much more sound and won´t loose much by ADDA. Transformers can do things like this: saturation, adding punch, overtone enhancment, phase shift, resulting in a more 3D sound, by letting the high frequencies later through the transformer...you can´t do this with plug-ins this great and natural. if you look at an analog mix bus, it´s often that there is a a line to mic signal converter, which gives you a low ohm, low gain signal and this is followed by a preamp. You´ll hear the whole preamp, not just the transformer. But the transformer has a major sonic imprint. If you look at a "normal" preamp design, like API, its an opamp going into a transformer. The shematic is very simple. You wont hear the shematic, you´ll hear an opamp feeding a transformer, while both have sonic shapes and the transformer does more than the opamp. There are many different transformers, some are "clean", some give you more sound, like there are API and NEVE style trafos out there. 16th March 2009 | Show parent #12 Lives for gear 🎧 15 years A word of caution: depending on the ratio of the trans and the load (Input) it's feeding just make sure your output circuit can handle the extra current... So if the output is an IC it may not be able to handle the extra load... If it's a 1:1 or 600 to 600 then it may not be an issue... If it's a 1:3 for example and feeding a 1176 (600 Ohm) then that will look like a 150 ohm load, or around that amount depending on trans... 16th March 2009 | Show parent #13 Lives for gear 🎧 15 years Quote: Originally Posted by Kenny Gioia ➡️ This is a brilliant idea based on the hype of transformers on this very site. But in practice, waste of time IMHO. Keep in mind, I know nothing about making gear but… This project would be the equivalent of putting a nice piece of analog gear into bypass. And a lot of those great transformers are impossible to find. Pultec, LA2a, Neve 2254s. So you'll be stuck with a high quality modern sounding transformer. At about$65 a pop, and using both an input and an output transformer on each channel, we're talking about just over $2,000.00 for a 16 channel unit that Superman couldn't distinguish in a blind A/B test. No? Quote: Originally Posted by UBK the sound comes from the entire output stage, which includes the trafo but is very much a sum total of the whole circuit around it. usually, the more toney boxes will also have some sort of custom op-amp(s) in there as well. I was curious too. I hung two Pearless 600:600 transformers off the back of my SSL compressor... no difference. I made two submixes in Protools, both going round-trip AD/DA, one having the transformers inserted. Flipped the phase and they null'd so far down it was silly. Sum is greater than the parts gang. This is why an FX386 doesn't sound the same as the same compressor in the 4000. A 1073 channel strip doesn't sound like a Neve console... No free lunch 16th March 2009 | Show parent #14 Kush Audio 🎧 15 years Quote: Originally Posted by juniorhifikit ➡️ No free lunch not only is the lunch not free, it tends to be quite pricey. there aren't many humans who are capable of designing a circuit such that what you put in invariably comes out sounding better; it takes a form of genius that is, in modern culture, generally scooped up by the military or large commercial interests. iow, those with the $$. take german mics and other broadcast gear post wwii; these were mostly ex-military engineers who were forbidden from working in any kind of military context anymore, so all these 'best and brightest' poured their talents into whatever other work was available. one of the fields that benefited from that was the state-funded broadcasting industry. the legacy of having that level of skill and technical/aesthetic understanding is still with us today, in the form of 10,000 tube mics. gregory scott - ubk . 16th March 2009 | Show parent #15 Lives for gear 🎧 15 years Quote: Originally Posted by u b k ➡️ not only is the lunch not free, it tends to be quite pricey. there aren't many humans who are capable of designing a circuit such that what you put in invariably comes out sounding better; it takes a form of genius that is, in modern culture, generally scooped up by the military or large commercial interests. iow, those with the$$$.

take german mics and other broadcast gear post wwii; these were mostly ex-military engineers who were forbidden from working in any kind of military context anymore, so all these 'best and brightest' poured their talents into whatever other work was available. one of the fields that benefited from that was the state-funded broadcasting industry.

the legacy of having that level of skill and technical/aesthetic understanding is still with us today, in the form of $10,000 tube mics. gregory scott - ubk . Fortunately, there are still some brilliant and genius designers with us today, but yeah, their stuff costs a small fortune. And it should. Nice job on the Fatso thingy by the way. Looks really cool. 8th August 2009 | Show parent #16 Lives for gear 🎧 10 years Broadcast Professional Audio - Looks like the right solution. £75 inc postage from Aus. Handmade too. The passive summing mixer looks rigt up my street too. 8th August 2009 | Show parent #17 Lives for gear 🎧 15 years Remember that a transformer is an inductor and is reacts differently with each type of circuit it is part of. The inductance changes according to the frequencies coursing through it as well. some type more than others. Some circuits more than others. I have a pair of DBX 161s that I have NOT modded into 160VUs. In place of the original circuit's balancing amp I have used an output transformer from a late '60s UA/UREI channel strip. The sound is quite different from either a 160VU or a 161. It is a damn good sound, but different. The output stage of the 161 reacts differently to the transformer than a 160VU's output circuit does. It also interfaces with the next piece of equipment in the chain in a different manner than a 160VU or 161 would. It is a valid sound, but idfferent from the original sound of the 160 or 161. As far as a 1073, 1081 or any circuit from a console sounding different than an actual console goes... If the device is is connected to the same components that would be between it and the recording device there would not be much difference. If the device is used as a stand-alone piece without everything that followed in a console it would sound potentially very different. This is why when I racked the two pairs of Sphere mic pres and 920/930 EQs I have re-created the component path from the actual console EXACTLY (remember I had the console for years prior to racking the pairs.) I have used the mic pres and EQs without the same output trannies and circuitry. They DO sound different. They are quite good sounding, but they sound different. I have also spoken to people who have stand alone Sphere EQs that do not have the BST circuit (fader amp) in use. These units also do not have transformers in place either. I can tell by talking to these people that they are not experiencing the true sound of the Sphere console. I was lucky that I was able to obtain a pair of original Reichenbach output transformers out of a Quad Eight. These were virtually identical to those that were used in the Sphere. Consoles are a "system" and if you only use one part of the "system" you generally can't obtain the sound of the "system." 25th October 2009 | Show parent #18 Gear Maniac 🎧 10 years I think with transformers and gear "color" in general is that it is additive and really needs to be stacked to really hear the difference. But I am looking into building one of these to go between my d/a's to my analog console. Then I can go ITB for super clean, OTB w/o transformer for some color, or with transformers for that real old vintage console sound. I think to really hear the effect you are going to need to run everything through it. So just strapping it on the 2-bus probably won't make enough difference to matter. Maybe do a summing box with transformers in and out. I think for me I will probably build a 16-channel box. But to keep the price down, check out Edcor transformers. They are M6 Silicon Steel for that color. Everything I have used them for I have been happy with. Plus they are around$10 a pop! Can't beat that!
2nd December 2009 | Show parent
#19
Lives for gear

🎧 10 years
What about running your mic into the XLR side of a passive DI,coming out of the 1/4" jack into the 1/4" jack of a second passive and then from the xlr out to your Preamp??? I know it sounds weird, but would it work, or could I hurt something???
17th April 2010 | Show parent
#20
Here for the gear

🎧 10 years
Hi have made many transformer connections for the sake of color and saturation. I use 1:1 600/600 output Transformers . prefer vintage . iron core

leaving the recording industry and setting up a home studio with limited budget and sub-par equipment means you have to do mods and become a diy person real quick.......nothing is handed to you on a platter.......what people are taking about and trying to get a handle on in this forum is the truth......Transformers are wonderful devices that can transform the sterile sound of cheap mixers and preamps into something much more presentable.

I use transformers after the mixer or preamps before hitting the sound-card....I even use a transformer into the inserts of the mixer to give me transformer sound ......I may or may not use one on the mix buss . Just the transformer in the signal path has an affect ...

I use Nuendo which has an external affect plugin that allows the use of external affects in the software domain. which also gives an opportunity to dial in the amount of transformer sound .....

I use Tamura Tk1 on the mix buss sometimes.....
I use vintage Ferrodyne's (I believe TRIAD bought them out)
I also have small wind modern transformers Edcore WSM600/600 .in total no more than a few hundred dollars worth of transformers .

You will notice a smoothness like a compression to the sound . The lows sound bigger , The middles become sweeter , the sound seems to become wider (probable due to phase problems in older Transformers) It's all had to put into words . but there is an affect .

Some people try to tell me that transformer don't have an affect on sound well they do .

I Nuendo I recorded a track.....no transformers used. Copied the track and reversed the phase , which nulls both tracks completely. I hooked up the external transformer to the soundcard in and outs .Put the Vst external plugin on the original and you can only hear the affect the transformer is having on the sound. I is there and loads of it.
7th March 2012
#21
Here for the gear

🎧 10 years
i tried this tonight, wired up to an input TRS jack and output TRS jack an edcor PC10k:10k i had bought for a diy remamping box project that never panned out. i love it so much that im gonna buy another one so i can run things out as stereo pairs. it gets rid of the MUD below 20hz and tightens the bass a bit, maybe not idea for metal kick drum tracks. but VERY VERY nice an usable. i ran a song mono\left output from Reaper, out of my m audio fast track ultra 8r and back into a line input. it sounds great, adds some type of THD that i like, and i foresee cheap steel core line input transformers in my future
12th March 2012
#22
Registered User

1 Review written
🎧 10 years
I remember trialling a cheap passive DI box - probably Phonic or some shit like that. I quite liked what it did to a bass I was playing with, and on the strength of that I bought my first Radial JDI. I was initially disappointed that the JDI was so much cleaner ... not at all the effect I expected. I love my JDI's for what they are, but don't understimate what cheap iron can do when you want a more overt effect.

DI's can be connected back to back for close to 1:1 ... I haven't tried it, but I could probably abuse my JDI's this way and probably make them saturate ...

I have many passive DIs, Reamps, line-splitters, Hum Eliminators, Line Level Shifters, and transformer preamps ... they solve so many problems, and generally I quite like the softening effect they have.

Transformers definately have a time-based effect, and convolution of transformer impulses is one way to get a little of this effect (maybe couple that with a saturation plug). Delaying the higher frequencies tends to make the sound softer even though they are still there ... this is basically what an All Pass Filter does, so that's another option.
12th March 2012 | Show parent
#23
Registered User

1 Review written
🎧 10 years
Quote:
Originally Posted by gurlygurl ➡️
so I could use a three-way, line level crossover and run the mid and high through separate delays (HF longer natch) and play Hass Effect games?
Why, yes! Yes - you could do that.

Feck all to do with transformer sound, but Yes - you could do that ...

12th March 2012
#24
Here for the gear

🎧 10 years
For me I really like the low frequency harmonic distortion. Not over the top. But it adds something nice
16th October 2012
#25
Lives for gear

12 Reviews written
🎧 10 years
doesn't look like anybody found the "tranny farm" yet.

dubolds "Tranny" farm

go on, click it, it's not dirty....
16th October 2012 | Show parent
#26
Gear Maniac

🎧 10 years
Quote:
Originally Posted by Brad McGowan ➡️
Get yourself some 600:600 ohm transformers. You'll need to consult the datasheet from the manufacturer whose transformer you are using to know which colored wire is what. But you basically wire XLR connectors to the input and output of the transformer. Simple as that.

If it's a steel core transformer you will experience increasing low frequency distortion with level. If it's a nickel core then it will sound really clean and you probably won't notice much difference in sound.

Just curious why you would use 600 ohm 1:1 tranformers? Why not 10k ohm if it's line level? Is 600 just a happy medium that wouldn't freak out if you put it after older gear vs. putting after the D to A outputs of your soundcard?

Looks like the Tranny farm action is to be inserted before the preamps they built it for. I wonder what the benefit of that would be sonically... putting a steel transformer in front of a preamp, after the microphone,,, in which case,, wouldn't you want to use a 150 ohm 1:1 transformer, if it's before the preamp? In that scenario, you'd probably have to hit it pretty hard (like with a kick or snare) before you started noticing any harmonic distortion.. I talked to someone recently who was explaining why it's the output transformer in well maintained Neve 1073 preamps from a certain era that give it the harmonic distortion and that the input transformer actually sounds very clean in contrast.. I'd really like to understand this better. I'd like to be able to wire up a couple transformers (but what impedance value) for use as an insert on my 2 mix.

Thanks.
16th October 2012
#27
Lives for gear

🎧 15 years
I'm going to scrounge up a bunch of old electrolytics and build a Sagging Cap Farm and sell it on EBay. Makes your gear sound vintage!
16th October 2012 | Show parent
#28
Lives for gear

12 Reviews written
🎧 10 years
Quote:
Originally Posted by jtienhaara ➡️
I'm going to scrounge up a bunch of old electrolytics and build a Sagging Cap Farm and sell it on EBay. Makes your gear sound vintage!
it'd be cheaper then the tranny farm i suppose.
16th October 2012 | Show parent
#29
Lives for gear

1 Review written
🎧 10 years
Quote:
Originally Posted by lerone ➡️
Broadcast Professional Audio - Looks like the right solution. £75 inc postage from Aus. Handmade too. The passive summing mixer looks rigt up my street too.
Here is a reveiw ofRob's products.

I totally agree with running thru transformers before your soundcard,

Depending on the quality of those you source the sound is smoother, richer.

I might get some more.
19th October 2012
#30
Gear Maniac

2 Reviews written
🎧 5 years
Definitely going to do this.

What would running a 1:1 transformer into another 1:1 transformer sound like? Too much like over-egging the pudding or more palatably saturated?

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