Transformers in tone sweetener pedals?

[triviani]

This one also uses a transformer

 

[Boneless]

Anyway, if you want to hear an example of a "colour" transformer (in this case a very cheap transformer), just play a Jack Casady and set the impedance knob to 250 or 500. Or remove the transformer in an SM57 and compare the results (you will need lots of additional gain). The transformer-less SM57 actually comes useful as a bass mic.

 

[sunbeast]

3 simple reasons

1. The ones that actually change your tone are large, like too large to fit in these tiny little pedals nowadays and no one wants big pedals anymore.
2. They are expensive.
3. Most modern manufacturers are going for as flat and clean (Jensen, Cinemag) as possible which doesn't give the tonal affect desired. Then it's just clean city. My 1960's UTC A-10 Transformer I used to create my DIY Motown DI has a massive roll off in the top end, my 70's UTC A-11 i used to create a DI for my Electric Piano has a low end roll off. They were never flat 20hz-20khz back then, so these modern takes just don't give the character needed.

I'd love the specs you used for your electric piano DI- my Rhodes is in need (ideally in stereo!)

 

[markjazzbassist]

I'd love the specs you used for your electric piano DI- my Rhodes is in need (ideally in stereo!)

for bass my UTC A-10 Transformer is +-2 db 30hz to 20khz, for electric piano (Hohner Pianet) my UTC A-11 Transformer is +- 2db 50hz-20khz. Tey are just passive DI, input, thru, XLR out, and ground switch, you can find diagrams online

 

[el murdoque]

That is correct Bogner worked with Rupert Neve on the transformer and circuit designs, transformers are an integral part of nearly every Neve designed circuit.

Bogner Releases Guitar Pedals with RND Transformers — Rupert Neve Designs

From the Bogner website : “Reinhold Bogner and Mr. Rupert Neve have teamed up to produce superb audio-effects pedals that serve up rich, buttery tones, ultra-dynamic response and a stunning three-dimensional sound quality inspired by the classic mixing consoles of the 1960′s. Each Transf

rupertneve.com

Great. Now I want one of those Bogners.

 

[MojoPin]

Doesn't the JHS Color Box preamp have a build in transformer as well?

Yeah, and I think it has one on EACH of it's outputs but don't quote me on that, I coulda sworn I heard Josh say that in one of their videos. It's a true bypass pedal though so it's only weakness IMO is that the XLR shuts off when the pedal is clicked off. Hence why I picked up the Super Vintage bass rig but with all it's ampeggy goodness I must admit, the color box will be on and off my bass board depending on the gig, it's really great swiss army knife to have in your inventory because it can really do so much. Glad I picked one up when they had their 25% off sale during the holidays.

 

[agedhorse]

3 simple reasons

1. The ones that actually change your tone are large, like too large to fit in these tiny little pedals nowadays and no one wants big pedals anymore.

Actually, it's easier to change the "tone" in a smaller transformer because it's difficult to get the necessary inductance and low frequency saturation headroom in a smaller transformer no matter what grade of core is being used. Especially when the transformers operate at higher dBm levels at low frequencies.

yeah those trannies are tiny in those pedals (pedals are tiny too!). more windings equals more tonal change. that lightning boy stuff is just marketing BS. Look up the Michael Jackson Bass DI, it's a UTC LS-50x, which weigh 20 pounds (they're also used in tube amps, mic preamps, etc.). why the bass sound huge on thriller album? because the tranny was huge.

Actually, more turns generally equals LESS tonal change at low frequencies because the primary inductance is higher for a given core material which reduces the frequency that saturation begins to occur, and different core materials transition into saturation differently.

EVERY parameter in a transformer is a trade-off, the generalizations being made are inaccurate standing alone without the context of all the other parameters that also change tone (and all in different ways).

 

[NitroBobby]

Are transformers used in these applications primarily intended to be tone shaping? I always looked at transformers used in audio applications as having more of an isolation function. Preventing any issues on the primary side from effecting the signal on the secondary, which would have an effect on the tone but not as the main focus. Also showing protection for the sensitive circuits the transformer is powering.

Am I off the mark here?

Thanks
kgb

 

[markjazzbassist]

Actually, it's easier to change the "tone" in a smaller transformer because it's difficult to get the necessary inductance and low frequency saturation headroom in a smaller transformer no matter what grade of core is being used. Especially when the transformers operate at higher dBm levels at low frequencies.


Actually, more turns generally equals LESS tonal change at low frequencies because the primary inductance is higher for a given core material which reduces the frequency that saturation begins to occur, and different core materials transition into saturation differently.

EVERY parameter in a transformer is a trade-off, the generalizations being made are inaccurate standing alone without the context of all the other parameters that also change tone (and all in different ways).

i replaced a tiny fender bandmaster transformer with a large (heavier and physically bigger) fender bassman transformer, and voila! WAY more low end, like ridiculous amounts. Went from a midrange machine to bass machine. I replaced a DI transformer from a tiny thing the size of a quarter and the height of a thimble with something the size of a a closed fist, and same thing, midrange machine to a proper bass representation. i also owned an old ampex tube mixer with these tiny beyerdynamic thimble sized input transformers, which overdrove when recording anything with low end, when replaced with large ampex input transformers, no overdriven bass, just clear clean low end.

 

[GrowlerBox]

i replaced a tiny fender bandmaster transformer with a large (heavier and physically bigger) fender bassman transformer, and voila! WAY more low end, like ridiculous amounts. Went from a midrange machine to bass machine. I replaced a DI transformer from a tiny thing the size of a quarter and the height of a thimble with something the size of a a closed fist, and same thing, midrange machine to a proper bass representation. i also owned an old ampex tube mixer with these tiny beyerdynamic thimble sized input transformers, which overdrove when recording anything with low end, when replaced with large ampex input transformers, no overdriven bass, just clear clean low end.

I think that’s more or less what @agedhorse was saying … You’re sort of arguing against your earlier statements regarding the tonal effects of transformer size: you felt that your tone was changed more (in a bad way) by the smaller transformers.

 

[becosfx]

Are transformers used in these applications primarily intended to be tone shaping? I always looked at transformers used in audio applications as having more of an isolation function. Preventing any issues on the primary side from effecting the signal on the secondary, which would have an effect on the tone but not as the main focus. Also showing protection for the sensitive circuits the transformer is powering.

Am I off the mark here?

Thanks
kgb

I think this is a great question, and while I can’t speak for everyone, here’s what I have to say. Back in the day, transformers were used because they were necessary for impedance matching and isolation which nicely prevented ground loops or hum and buzz noise. Their particular characteristic influenced the sound of the gear they were used in. When silicon components became common, transformers weren’t used as much since they’re bulky, heavy, and more expensive. As silicon and digital technology improved, some felt that something was missing from the sound. Vintage circuits seemed warmer and had a bit more life in their dynamics compared to the clean and transparent sound of modern designs. Old tech like tubes and transformers were definitely missed for how they shaped the sound.

Now, audio transformers in small amplitude circuits can still be used by choice to add that vintage feel. They’re used in power amps for instruments and music listening for this very reason. That’s why we also include them - because we feel they add something extra to our modern circuits. The devices we make feel more “complete” to us with a bit of that vintage vibe. It’s not just in our heads; it’s real. Transformers do bring something special, and if someone wants that, they should have the option, even in modern gear.

Of course, there are limits, like their size and cost, but we’ve tried our best to offer something more that’s actually useful. We also designed them to give a balanced output for direct use in the studio and on stage. We could’ve done that with silicon alone, cheaper, but why not strive for something more and add the touch of that vintage character on top of high performance? That’s the thinking behind what we do and why we do it.

 

[NitroBobby]

I think this is a great question, and while I can’t speak for everyone, here’s what I have to say. Back in the day, transformers were used because they were necessary for impedance matching and isolation which nicely prevented ground loops or hum and buzz noise. Their particular characteristic influenced the sound of the gear they were used in. When silicon components became common, transformers weren’t used as much since they’re bulky, heavy, and more expensive. As silicon and digital technology improved, some felt that something was missing from the sound. Vintage circuits seemed warmer and had a bit more life in their dynamics compared to the clean and transparent sound of modern designs. Old tech like tubes and transformers were definitely missed for how they shaped the sound.

Now, audio transformers in small amplitude circuits can still be used by choice to add that vintage feel. They’re used in power amps for instruments and music listening for this very reason. That’s why we also include them - because we feel they add something extra to our modern circuits. The devices we make feel more “complete” to us with a bit of that vintage vibe. It’s not just in our heads; it’s real. Transformers do bring something special, and if someone wants that, they should have the option, even in modern gear.

Of course, there are limits, like their size and cost, but we’ve tried our best to offer something more that’s actually useful. We also designed them to give a balanced output for direct use in the studio and on stage. We could’ve done that with silicon alone, cheaper, but why not strive for something more and add the touch of that vintage character on top of high performance? That’s the thinking behind what we do and why we do it.

Thank you. I appreciate the response.

kgb

 

[agedhorse]

I think that’s more or less what @agedhorse was saying … You’re sort of arguing against your earlier statements regarding the tonal effects of transformer size: you felt that your tone was changed more (in a bad way) by the smaller transformers.

Correct.

 

[Gorilla Monsoon]

Audio transformers are a very, very complex topic full of tradeoffs that are often at odds with the goals of the designs.

Much of my experience with transformers is centered around pro audio, where they are generally preferred to be transparent and to either provide impedance matching with a corresponding level shift, or for galvanic isolation in environments that may have high common mode voltages between the chassis (for example, transmitting analog audio across a large complex or campus). I have also worked on a number of tube amp power and output transformers recently, but there are additional safety parameters that influence these designs which can not be ignored.

Every single design choice affects every other performance parameter. For example, if you need a high z input and low z output, if the transform ratio becomes too high, the frequency response will suffer (especially high frequency) and so will the distortion and isolation. If you need isolation and the input level equals the output level, both the source and load impedance become more important because the source impedance can't be higher than the load impedance or there will be a large level drop (there will be a level drop anyway, unless the source z is much lower than the load z).

If you need very high isolation, especially at high frequencies, then an electrostatic shield between the two windings will be necessary, this too affects the frequency response and for extreme isolation, dual electrostatic shields that are isolated from each other might be required, one for the primary and one for the secondary.

With lower impedances and higher currents, different grades of core material might be necessary, and if the core size grows, the coils grow which increase the amount of copper (wire length) which increases DC resistance which might require larger wire to overcome, which again changes the geometry whit of course affects every other parameter.

A transformer development project that I worked on several decades ago resulted in a 1:1 isolation part with dual electrostatic shields that was 0.5dB from 20Hz - 20kHz and was 3dB down at 85kHz, and less than .25% THD from 20-20kHz at 0dBu but was still only 0.5%THD at +20dBu. IIRC, the common mode voltage rating from primary to secondary was over 500V. A LOT of design and manufacturing tradeoffs were massaged to make this part viable.

Now if you want a transformer to have "color", you need to manipulate these tradeoffs in a way that gets what you want without torpedoing all of the other performance parameters. It's harder than it looks, and usually it creates new and previously undiscovered flaws in the end product unless you quantify everything thoroughly.

Mang…we are lucky to have this guy.

 

[scubaduba]

Becos Stella with DITOS and the Niche Devices Humboldt. Thank me later.

 

[Johno Dunn]

Becos Stella with DITOS and the Niche Devices Humboldt. Thank me later.

Plus one on the Humboldt!

 

[smo]

I personally find the Radial JDI to be pretty good.

 

[Ritter667]

Sounds good to me:

 

[Ragemous]

Here ya go!

 

[ImTheOnlyOne]

I'd like to see how many of them you need to stack to degrade the tone to unusable.

Three. In a row.

Really, IME.

I have two 2020+2020S pairs in the effects loop of my preamp that I don't want to like so much, but do. Pedals in between and after boost the signal, offsetting degradation.

They improve the behavior of the downstream compressor, compress bit themselves, rounding the tone, add subtle grit, and improve recordability. Because of their effect on impedance, placement matters. Three up front loaded down my passive Jazz pickups badly..