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Conspiracy to Commit Electronics Megathread
- Thread starter Sushi Box FX
- Start date
I would guess you are looking for a spectrum analyser or something similar, I have never used one or anything like it but hopefully someone else knows exactly what you are after.
There are free apps and online spectrum analysers out there but you would have to do some research to see if they would do the job for you.
If you do find something then could you come back here and let us all know ? I'm sure many of us would be interested, especially if it is free and easy to use.
Cheers
Mick
There are free apps and online spectrum analysers out there but you would have to do some research to see if they would do the job for you.
If you do find something then could you come back here and let us all know ? I'm sure many of us would be interested, especially if it is free and easy to use.
Cheers
Mick
just use room eq wizard with a loop back
www.roomeqwizard.com
REW room acoustics and audio device measurement and analysis software
REW is free software for room acoustic measurement, loudspeaker measurement and audio device measurement
www.roomeqwizard.com
Well, I took the Particle Accelerator to band practice last night, first time to use it LOUD, not at home. We were at one of those rent-by-the-hour places, and the stock amp there is a Hartke HA3500, which I don't like a lot; I plugged the PA into the FX return, and maybe it's because I play harder with a full band than at home, but I definitely got some dirty tones last night. We do a couple of songs (Neil Young, Stones, The Band) where I use a pick instead playing finger style, and I got a particularly dirty late 60s/early 70s rock tone that way; our guitar player loved my sound, said I should bring the PA every time in the future.
I was just looking at the Particle Accelerator PCB I got last week and I was wondering what to do with it, I already have a stock one.
I was wondering if I should make a Bassman 731 pedal or a Showman AB763 pedal and it made me look at the tone stack a bit more.
The Bassman has a 22k resistor for the Mid pot and a deep switch which adds another 100nF cap into the tonestack, I changed the Mid pot to 20k, 25, and 50k in the TSC calculator and I noticed the loss in the tonestack halved with a 50k pot.
If you halve the loss in the tone stack you must have more gain going into the second tube stage, I was wondering about the tone getting dirtier with the extra gain with a 50k pot in there.
I think I will have to go with a 50k Mid pot and change the capacitors to the same value as the Bassman when I build the next one,
Here is a picture of the "Flat Setting" in the PA tone stack with a 10k (bottom), 20k, 25k, 50k (top) Mid pot in the circuit, the bigger the pot the better the gain will be in the circuit.
I was wondering if I should make a Bassman 731 pedal or a Showman AB763 pedal and it made me look at the tone stack a bit more.
The Bassman has a 22k resistor for the Mid pot and a deep switch which adds another 100nF cap into the tonestack, I changed the Mid pot to 20k, 25, and 50k in the TSC calculator and I noticed the loss in the tonestack halved with a 50k pot.
If you halve the loss in the tone stack you must have more gain going into the second tube stage, I was wondering about the tone getting dirtier with the extra gain with a 50k pot in there.
I think I will have to go with a 50k Mid pot and change the capacitors to the same value as the Bassman when I build the next one,
Here is a picture of the "Flat Setting" in the PA tone stack with a 10k (bottom), 20k, 25k, 50k (top) Mid pot in the circuit, the bigger the pot the better the gain will be in the circuit.
Attachments
A 50K Mid pot also really digs into how much relative power the Bass and Treble controls are capable of though, at least until you start dropping the Mids control down significantly. You also move the mid scoop down in frequency that way (which I'm sure you cn compensate for by changing some capacitor values)
I am not sure I understand what you mean with the mid scoop down in frequency, if I replace the 10k pot with a 20k pot the 20k pot will behave exactly like the 10k pot from 0 to 5 on the dial and anything at 5 to 10 is just extra adjustment.
A higher value pot just helps reduce the mid dip but nothing else changes, you can get the same settings when the new pot is set between 0-10k on the dial.
I made a graph showing the mid dip difference between a 10k, 20k, 25k and a 50k pot, when the mid is on 0 they all have the same curve but the higher value pots can just reduce the dip more.
A higher value pot just helps reduce the mid dip but nothing else changes, you can get the same settings when the new pot is set between 0-10k on the dial.
I made a graph showing the mid dip difference between a 10k, 20k, 25k and a 50k pot, when the mid is on 0 they all have the same curve but the higher value pots can just reduce the dip more.
Attachments
You are right- I think I must have accidentally adjusted the Bass pot value at the same time to get that drop in frequency as I can't recreate it now!
In any case, I think the 20K Mid pot would probably be my compromise to not lose as much overall gain while still allowing a decent amount of Bass/Treble boost. Could be an interesting mod to use a 50K pot with a switch to engage a resistor or trim-pot across the pot as a gain booster/attenuator setting. Could be interesting to play with the mid arrangement of the TS-50B as well, which uses the Fender stack arrangement for Bass and Treble but the Mid is a different passive topology.
Could you explain what you know about the ts50b equalizer? I own the aion ts50b and the broughton Helion. What are the mid doing?
I am not super educated in the theory behind this stuff, but the Traynor Mid control uses what's called a Twin-T Notch filter placed in the circuit before the Bass/Treble controls. Here someone modeled it, and you can see the response by sliding the resistance slider on the right- turning it up gives a flat response, turning it down drops the frequency of the notch center while also increasing the notch amplitude. I'd be curious to see a model of the entire circuit placing a more typical Fender tonestack after the Traynor Mid circuit (if I'm not mistaken, the Treble/Bass part of the Traynor circuit still creates a mid notch of its own here unless turned down to 2 or so like a typical Fender tonestack, even though the Mid pot is omitted from that part of the circuit): https://www.falstad.com/afilter/circuitjs.html?cct=$+1+0.000005+5+50+5+50 %+0+28853.998118144256 c+752+336+864+336+0+4.7000000000000004e-8+0 c+864+336+976+336+0+4.7000000000000004e-8+0 r+864+336+864+400+0+1500 g+864+400+864+432+0 w+976+176+976+256+0 w+976+256+976+336+0 w+752+176+752+256+0 w+752+256+752+336+0 O+976+256+1040+256+0 170+752+256+704+256+3+40+80+5+0.5 174+752+176+976+176+0+15000+0.5+Resistance w+864+160+976+160+0 w+976+160+976+176+0 o+9+32+0+34+5+0.025+0+-1 o+8+32+0+34+5+0.00009765625+1+-1
Here is the Mid in context of the circuit (all the cut paths at the bottom go to ground):
The most interesting part of the Traynor circuit comes after the tonestack- the signal gets cut into three frequency bands that each have their own clipping transistor, then are recombined. So each frequency band is clipped independently (not directly related to the tonestack, though boosting/cutting the tonestack will affect the gain at different bands since the tonestack comes before the clipping circuit)
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Thank you so much. It makes much more sense in my head now. I really appreciate you.
If anyone is interested in learning more about the Fender tone stack Rob Robinette has a good article on it that is easy to understand.
Has anyone finished a Steddi Go! yet?
Unagi/ Tung Sol
I've got a Lightning Boy transformer and some other tubes/knobs for the next two.
Unagi/ Tung Sol
I've got a Lightning Boy transformer and some other tubes/knobs for the next two.
Here's another one.
Lightning Boy transformer/ Tung Sol
I had a Mullard in there to start but it kinda stunk, to be honest. Noisy and cut some low end…
I also love single knob stuff because of the opportunity to use a cool knob.
Lightning Boy transformer/ Tung Sol
I had a Mullard in there to start but it kinda stunk, to be honest. Noisy and cut some low end…
I also love single knob stuff because of the opportunity to use a cool knob.
Nice build although it sort of looks like you missed soldering the mounting lugs on the pot, maybe it's an optical illusion.
You're right! I did miss that one but got the other side.
I finished another Steddi Go!
This one has Unagi transformer but a TAD au7. I think it sounds the best. I guess it's the lower gain tube?
This one has Unagi transformer but a TAD au7. I think it sounds the best. I guess it's the lower gain tube?
The Steddi Go circuit is near-identical to the Ampeg SVTDI and likely also Khan VTDI; both of which use a 12AU7 tube. Maybe that's the preferred tube in this application. I imagine that a AX7 is a bit too gainy.
I'm waiting for Musikding to provide a complete Steddi Go kit, so I can build one for a bandmate as he wants a tube DI for acoustic guitar.
I'm waiting for Musikding to provide a complete Steddi Go kit, so I can build one for a bandmate as he wants a tube DI for acoustic guitar.
