Just curious if anyone here got one and if he did any mods..I have one...about a year ago it almost blowed down because of some bad soldering joints it had..at this point the tech offered me to mod it to sound more like a marshall JMP..now it takes EL34s and it's a bit rounder, plus I got a built-in 9db attenuator..anyway I still am not so satisfied..I play garage/punk and I run it very high volume wise, it has a strange smell, no cap smell but something not so nice..plus I still hate how it...

Okay so I got this tube mixer that is just old and funkay!

But I am going to put it in a new rack sized chassis and will mod it, but Im wonderinf where I can find info on it..

Its not all origional or anything like that..so value is just the sum of its parts..but maybe one of you out there have a better clue than me. :)

the piccie is upside down.... :slap:

As you know from our Mojo-Experts the type of solder can have a big influence of the sound. Many years ago Guild recognized this problem and to avoid any negative effect on the sound didn´t use any solder as you can see here:

more info here:

analogguru

Hi, theres no SS amp forum here so I thought I'd post it in here!

The Squier SP-10 is a terrible amp on the dirt channel, and the EQ isnt great either; but the clean channel is nice, so im gonna remove and recycle the OD channel & EQ components and make the amp permanently on clean, and build some pedals inside the enclosure.

The circuit has two JRC4558Ds (most likely for clean boosts) and two anti-parallel diodes..possibly for clipping (forward V of: 700mV) The PA section seems to consist of...

any chance one of you guys have a schematic for an ampeg b50r?

I have a Marshall AVT 50 head, and over at the Marshall Forum
a fellow claims to have figured out some mods to fix a few of the complaints
with the amp. He has since not been around to answer questions.
Here is what he says about it.

I came up with some great modifications for my AVT50 amp:
1. The obvious mod: add a second speaker jack.
2. Installed a clean channel midrange control.
3. Increased preamp tube gain by around 25% (switched).
4. Installed a 6 position mid shift switch on the...

I've been trying to find information on these but so far what I have found is limited
I did find gutshots on the ESP forums though :D

not all valve as is stated on most of the retail sites, several fets and op amps in there, apparently its the preamp that is hybrid and the power section is a 12BH7 valve running in push pull config.

Alos they seem to have some issues

I like the way they sound, I'm considering trying one if they manage to sort out the issues

Anybody have the modular amp schematics from randall for the egnater designed stuff? :)

Hi folks,
Besides all the classic mods for all these 5W class A tube amps (you know : AX84, Epiphone Valve Jr, Harley Benton GA5, Blackheart, Ibanez Valbee, Peavey Nanovalve, etc.), i was wondering how i could add some vintage tube tremolo circuit.
( briggs, you're not the only one with a hole to fill in a Valve Jr. :wink: )

Most of the tremolo amps are in fact in push-pull configuration, and the class AB bias point is modulated by the LFO.
I've eventually found 4 ways to get tremolo in a...

At least I think it's a lamp.
Has 2 small filaments and I lit it up (dimly) with 24vac 3, 6, 9 or 12 wouldn't light it at all. It has a Octal base is GT size and has pins at 1,2,3,5,7 and 8. Pins 2 & 7 have 12.5 ohm resistance and those light it but none of the other pins have any continuity.

I have a 49 Sylvania Technical book also googled but couldn't find anything what so ever :scratch:
Anyone have the data sheet? I don't want to keep cranking up the juice until I burn it up!

Here are...

Hi, i picked up a traynor mark 3 yesterday (250$), but its distorting really unpleasantly. When the master volume channel has the preamp cranked, no matter where the master is, its got this distortion. When i crank the non-master volume channel, its there too, and its also very quiet for an amp thats supposed to be as loud as the twin. The distortion sounds like very bad solid state distortion, and its not dynamic at all. Whats my problem?

I've got an SLP on the bench that is very quiet. When I crank it the loudness sounds to be about 10W even though it brakes up as if it was at full volume. The voltages seem to be fine and I've tried new tubes and different cabs but the issue remains. If anyone could help me solve this puzzle I'd appreciate it. I'll post my voltage readings tomorrow.

Thanks

heard of some clips online and liked it a lot
is there any schem lying around?

dont suppose anybody has the einstein schematic :D

Hi, first of all, thanks for this forum, great inspiration! In was wondering what kind of power soak/attenuator or whatever I should build for my tweed champ clone - it's still too loud for a city apartment, the neighbors, you know. The sound shouldn't be altered too much by the device. Maybe I should mention that I know a bit about electronics, I used to work in a TV-repair shop about 15 years ago, but I forgot a lot. Still, I know how to solder, how to read a schematic and I already built...

Hi guys, I make a small meter to bias tube amplifiers
Here is a schematics and pictures how I make this meter:

And the ready to use tester :)

Hi there!
I'm going to build a simple Ax84 Hi-Octane version, but i've got in my hands a 260V-0-260V (40mA+40mA) Power tranny (instead of the 190-0-190 suggested for this project). A solid state rectified 260V gives me approximately 365V on the B+ tap (i'm using the Duncan Amp power supply software for the simulation) . Isn't it a bit too much for an EL84?
Could i lower B+ voltage with a resistor in series after the rectifier, without loosing too much current ? Any suggestions?
Sorry for the...

Hi,

I have recently been given a vintage Leak Trough Line Stereo, an all-valve stereo FM Tuner from the '60s, and was just wondering if by some chance that it could be made into a valve guitar amp???

The Trough Line is in pretty good condition, looks really nice, all vintage Mullard valves, all point-to-point wiring, serious mojo :wink:

I haven't tested it out yet (has a vintage 2 prong plug so can't test it unless I change this to UK 3 pin), but it should still work! I wouldn't mind...

Dear friends, here is a gibson master service manual book

This book contain 513 pages with gibson amplifier schematics. Most of them are tube schematics, other solid state.

Enjoy

I use old transformers from Regent 60 - German tube amplifier - 2xEL34 tube power amp.
I make my own enclosure.
This amp is based over fender twin reverb preamp + send-return, and classic tube amplifier. I make some modifications and now I use russian 6l6 analog - 6p3s-e

Enjoy the pictures:

Hello to everyone! I am new in here but not new to the field. I have been building guitars for a while and have been getting into building effects and now amps.

So, my question is, how can I remove a tremelo out of a circuit when it is bias modulating? Example would be maybe a Sears 1482 amp but I want to re-create is without the tremelo. Or any amp for that matter. I want to mess around with a simple clean circuit but I don;t want a tremelo on it. Thanks and I will try to contribute too as...

I'm fixing up a friend's old Stromberg-Carlson amp for his use w/ guitar. I want to set up the output tubes (2x6L6) to have separate cathode resistors and capacitors. The one problem I'm having is that the filament winding has a 100 ohm hum balance pot with the wiper going to the (presently) tied together 6L6 cathodes (which has 25v according to the schematic). Should I just take the wire and connect it to ground or is there some place better to put it so it's getting a similar voltage?

Anyone have any for the Rocker series?

Just wondering if any of you use a Fender Blues Jr. If so, have you modded it? I'm aware of the . Anybody know what all he did? Brian, care to share your modifications?

I just got the amp tonight, so I've only been able to play with it for about 5 minutes. I noticed something strange about the tone controls... The mid control seems to suck out all of the mids when turned below noon, and gives a hell of a boost when past noon. Also, the bass and treble controls don't really seem to do anything....