How do you register for the Peavey site?
All I get is a credential request,or error 404

Its kinda late to go over those mods you listed,I will later.
I appreciate the answers.
I asked elsewhere about the common 2k7 cathode resistors and was told the cooler bias was a trade off for the filter effect when using a bypass cap.
However since the triodes here dont have cathode bypass caps,I wonder why they would use that value over 1k5,
I think 1k5 cathode resistors would be an improvement like your OPA hifi opamps(which I want to try now after your glowing endorsment)

Can you enlighten me on the 5 x 1n34A set up you refered to?
I to like using them on occasion,but am unfamiliar with a 5 diode bridge rectifier,sounds very interesting.

That is strange I have a tube amp that makes that exact same noise when you unplug the cord from the input.
It only lasts for a few seconds and only when you unplug from the input jack.
I have checked several times and cant find anything wrong no bad connections or voltages outa whack.
I hope someone else might know what your problem is,so as to help with my similiar issue.

I think you meant Hz and Khz not Mhz as that would be way beyond the range of any instrument I know of.
The usual HiFi range is 20hz - 20 khz
Just clarifing for others who may not know the difference,

Thanxs Eric I threw you a chip point for that!
The old data at SLM is no longer and no link for schematics.
The people here have been kind enough to send me schematics for most of my old Crate stuff,but I will e-mail them and see what they send.
I love Crates they are cheap and everywhere the way VWs used to be.

Wow again it looks really nice Joe!
Cant wait to see more.

What kind of sound do the 4X4148s to ground give after the first triode?
I just tried something similiar with red LEDs and found 2 sounded great but 4 only added a little dirt not very noticable.
How does the low plate voltage affect the clipping the make?
My triodes are closer to 250V- 300V plate voltage 80v seems low.

Also why are they biased with 2k2 instead of 1k5 or 820r?
Is it because of the low plate voltage?

And finally have you tried added a bypass cap to either triode?
Seems like the first one could have a 4.7uf on a switch for a nice warm boost or even a .2 - .68 for some top boost .
Thanxs for sharing the schematic and pics,Its nice learning about new stuff.

Quote from: teemuk on November 03, 2009, 12:25:49 AM
See those resistive dividers within the clipping gain stage, (R27, R31, R30, R29, R28)? Change the ratio of those dividers and you can shape the clipping harder or softer.

Thats what I was going to say try changing R28 to a 100-250K
That might smooth it up into some classic rock type gain.
Edit - Or you could try a 100k - 1M pot for R28 and the one next to it 18K with a 20K pot then dial em to see what sounds good and measure the pots when you get the sound you want and replace with fixed resistors.
Also 1N5711 diodes sound alot smoother and less buzzy than the 1n4148s in there now.

I just about finished putting a 4 gain stage Marshall type tube pre amp(a modified Dockery TMB in cascade mode with selectable boost and an NFB circuit) into a small SE amp (Valve Jr).
I added an FX loop right after the MV breaking directly before the input to the power tube
an EL84.
I can drive anything with it !!!!!!!!!!!
Seriously with the MV down I can drive the input of any of my SS gear.
And it sounds sweet.
And it works super going into another tube amp as well.
Still needs a boost in front to get the gain I am after  8| But wow with some drop tuning
it is the $h1T.
I see no reason why a Hybrid tube pre/SS PA shouldn't be as simple.
FWIW the Dockery pre uses a cathode follower into the PA and it made the tonestack sound better to me.So the last stage is a CF followed by the TMB tonestack and then into the MV into the FX loop into the EL84(PA)

Yeah Joe I found the same thing with most chip amps they need more than 1V input.
I thought the question was in regards to limiting the input to 1 V for a certain chip.

The tip will connect to the "IN" of the circuit.
The sleeve will connect to the "ground" of the circuit.
have fun

If you search this site you WILL find it along with the owners manual,happy reading.

http://www.ssguitar.com/index.php?topic=1212.0
Uses car amp chip,runs on 12-18V and yeah AA batteries about 2 hrs full volume.
The TDA20** series have more info available as far as projects go.
So I have done what your asking and it works great,IDK about the battery from Frys
but that sounds about right,and I could use two of em

Thats insane he's lucky to be alive.
You could try removing the input jack then unsoldering all the components where the board has turned color.
Use some acetone and clean it up real good so you can inspect the traces.
Find the schematic and replace those burnt SMD components(if there is enough of the traces left)
Then if it still hums IDK I would check all the electrolytics with a meter to see if thats it.
A bad filter cap can make a bad hum and they dont like the wrong polarity voltage.
Beyond that (and thats alot of work but not impossible)Yeah its probably spare parts.
So a few hours patient work for a maybe,but no outa pocket expense minus a few passive components.

I really like it Sergscar !!!
And more important you are very happy with it to!
How does it sound with your 386 pre-amp?
You should be able to overdrive it with that too.
Yes I am looking forward to the sound clips,
Best wishes to you Serg in SP,Brazil
from Bryan in Mohave Desert, USA

Sounds like it fried some caps,try to find the schematic,write to Spyder if you have to.
Taking pics of the insides of the amp might prove helpful too.
Let us know.