Simulcast with a transformer bypass switch

Fontelroy

Active member
Howdy folks!

This was a pedal I always wanted to try as I'm a fan of Ariel Posen, who I think used it and has a signature version of it. I was also quite curious to see if the transformer makes much of a difference in the circuit as I know a fair amount of folks have said it does not and I'd imagine the folks that make and sell the Broadcast would say it's an important part as it's mentioned in the description of said pedal on their website. Now with the music gear world full of all sorts of claims and marketing lingo from 'mojo parts' & 'vintage vibes' to 'transparent overdrive' I think the best thing to do is test stuff yourself.

All that being said, I wasn't exactly impartial going into this after some experience with cheap iso splitters; my theory was that the transformer would have some effect on the sound. But also in the back of my mind was this
video where the guy tested a variety of transformers and their varying degrees of effect to the signal - Not exactly an apples to apples comparison with a guitar pedal and instrument signal, but I thought the same principles would be at play.

Anywho, on to the testing!

Here's a pic of the recording in Audition. Yellow is when the transformer is in the circuit, red is bypassed.
Screenshot 2024-04-09 013640.jpg
here's a different recording with a little more playing - I can hear a small difference, but nothing that'd make me think I was playing a different pedal. I should also mention that since I'm not showing it in any pics of the audio or in a recording the difference between bypass and having the transformer in line didn't exacerbate much with any settings changes I made to the knobs. Knobs maxed out or at 2; nothing got particularly more drastic. It seemed to be slightly more noticeable with the pedal in its highest gain mode on the 3 position switch, but that could also just be due to the added noise, but I never got the sense that the transformer itself was distorting which was something the hudson website alludes to in the description of their AP variant.

Here's a pic showing the build:
IMG_7299.jpg IMG_7300.jpg

One thing that's important for the test is to completely bypass the transformer so using an spdt switch (like you can use when if you were selecting between clipping diodes for instance) wouldn't cut it as the transformer would still be loading down the circuit as mentioned in the youtube video linked above.

Conclusion - does the transformer play a vital role in the sound of this circuit? I would say the answer to that is NO. But it does affect things a tiny bit.

Small disclaimer - I did not have the exact transistors the build called for and made due with some subs - originally a BC549B but recorded was an MPSA18 & ASX12C. Given the test, I don't believe the BOM listed transistors would make a difference to the final result but I thought it was noteworthy.
 
Last edited:
Thanks for posting this! I recently built one of these using the Aion Skywave PCB and was also wondering what effect, if any, the transformer has on the overall sound. I also recently built a British Royalty (Greer Royal Velvet) and was wondering the same thing. I will say that both pedals sound VERY good to me so far, so the transformers aren't hurting anything. At worst, I'm out an extra $5.50 per build. They do look cool, at least.
 
Thanks for posting this! I recently built one of these using the Aion Skywave PCB and was also wondering what effect, if any, the transformer has on the overall sound. I also recently built a British Royalty (Greer Royal Velvet) and was wondering the same thing. I will say that both pedals sound VERY good to me so far, so the transformers aren't hurting anything. At worst, I'm out an extra $5.50 per build. They do look cool, at least.
the duocast is my favorite pedal so i'm excited to build the british royalty (it's on the way). the other transformer pedals i've built have been awesome as well. i think it's the key to the "console-style" saturation sound.
 
Very interesting test! As always, all these things count, but it’s not in a particular component where the magic usually stays. Mostly in a whole setup working together, and in guitarist’s fingers.
I’ve built the Duocast and I’ve ordered an Aion Skywave pcb as well.
By the way, sorry to go off-topic but anyone knows which positions go where for the gain mode switch in Skywave? I’m doing the artwork way before I have the BOM. @KT88 ?
 
Very interesting test! As always, all these things count, but it’s not in a particular component where the magic usually stays. Mostly in a whole setup working together, and in guitarist’s fingers.
I’ve built the Duocast and I’ve ordered an Aion Skywave pcb as well.
By the way, sorry to go off-topic but anyone knows which positions go where for the gain mode switch in Skywave? I’m doing the artwork way before I have the BOM. @KT88 ?
From top to bottom, you have medium gain, low gain (middle position) and high gain. Those are the positions on mine, anyway.
 
My Friend and I were playing around with his T&T Varitone pedal last night and the switch that swaps in and out the choke (transformer) definitely made a difference.
It's a bare-bones circuit. Just caps on a switch through the transformer (or not) and a pot to control how much signal gets bled through the caps to ground.

If I build a Varitone pedal, I'll probably leave off the switch, as last night I preferred the transformer always on.
 
Back
Top