Pre-amp/Distortion Pedal

[Shakal]

I want a clean/distortion preamp in the same circuit because its way better than put 2 circuits in one box and then make a switch... I'm a begginer, so it's harder to make mistakes in one circuit than two circuits...

I wanna know if there is a commercial pedal that does that, and a clone for it.

[rogeryu_ph]

I'm not sure but you could built this one.
Real McTube II
This uses a 12ax7 tube valve
http://www.dogstar.dantimax.dk/tubestuf/mctube.htm
check out and download the PDF project file on TONEPAD
http://www.tonepad.com/project.asp?id=23

I'm looking forward to do this project also good luck,
Roger

[Shakal]

Ouch! Valves!

Too newbie to deal with this hot tubes, for now... Need to make one more, or two to get the feeling.

I'm looking forward to make the Bass Driver DI right now. It getting hard because I don't have a layout, just the schem, I'm trying to do it on my on, but it's really hard!

But thanks anyways!

[snoof]

As stated earlier in this thread, just build a TubeScreamer and make the diodes switchable.  No diodes, no clipping(unless CRANKED), switch in diodes, distortion.



this switches between two diff pairs of diodes, just leave off one of the pairs and you get boost instead of dist(using a on-on), or use it as shown, and have 3 diff settings(with a on-off-on toggle).  you can even use a stomp switch for the selection(on-on setup).  There are many many layouts and schems for the TS.

[rogeryu_ph]

Hi snoof,
Yeah you are right I was just doubting that my TS9 re-issue and Clone TS808 was lacking in warm overdrive and I read this RMT would satisfy my taste in OD setup co'z its a valve concept. This will be my last priority if ever. Can I ask one question? Whats the different in using Tubescreamer in non-tube amp and a tube amp?
I know this was design use for tube amp. 
Thanks,
Roger

[ZeroGravity]

About switching the diodes in or out: won't you have an enormous boost in volume when they are switched out?
Apart from clipping the signal, the diodes also lower the output volume, because when they are conducting, they have a very low impedance.
I'm experimenting with a preamp/overdrive circuit for the moment, and I thought about switching the diodes AND at the same time a resistor to lower the overall gain of the amplifier.

[snoof]

on a TS clone I have, there is a bit of boost, but hardly noticable.  It depends on what diodes you use as clippers.  GE diodes will give you quite a boost when switched out, 4001's, 914's and LED's not as much.

[bonkdav]

this seems really interesting, would it be possible for me to build an lpb2 or an amz mosfet booster and then add switchable diodes to ground from the output for distortion and then tag the octave portion of the octavia on there just like the octo booster (make it bypassable) and then possibly another clean boost on the end to make up for any volume loss ?

clean boost > diodes > octave transformer > clean boost > output pot

im planning on making the middle 3 bypassable with switches

any concerns or thoughts feel free to tell me whats up

[snoof]

this seems really interesting, would it be possible for me to build an lpb2 or an amz mosfet booster and then add switchable diodes to ground from the output for distortion

Sure.

then tag the octave portion of the octavia on there just like the octo booster (make it bypassable) and then possibly another clean boost on the end to make up for any volume loss

it might be easier to just build the octo-booster and switch between the "octave section", and a "diodes to grnd section".  The switching might take place after the 100uf cap, but before the transformer.  Then you'd have fuzzy octave, or OD/dist.  There might be a level difference betwixt the two settings though...

[bonkdav]

yeah i was worried about the level difference, especially if i use ge diodes, maybe i can get a dual gang pot and tweak one with resistors or even replace the wafer. or get the clean output to match level with the diodes with some sort or trim and have that on the switch as well. and use the second boost to get it back to a good volume. i have numerous 3pdt switches and even a 4pdt that ive scavenged off record players and cb radios so im not too worried about getting the switching to work.  I think this will be great for my first breadboarding experience and hopefully something useful will come out of it.  Hopefully ill have a build report within a few weeks.

Thanks for the advice snoof

[Chris Frailin]

For a friend, I built a TS-808, with a switch to knock out the clipping diodes, so when the diodes are out, it's a preamp (with the signature mid boost) and with the diodes in, full-on OD. Also included an extra pot in the FB loop for when the diodes are out, so you can change the preamp level without effecting [sic] the OD  level.

You mean he built a Fulldrive?  Maybe he could put in Fuller's FM circuit too.