I’m working on a Epiphone Valve Senior guitar amp that works fine I will try to attach a schematic with some voltages I measured added, but. Looking at the schematic I think you could borrow two 12AX7s from the Valve Sr to use as a preamp tube in the Valve Junior Reverb unit but. Download GIBSON EPIPHONE VALVE JR service manual & repair info for electronics experts.
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Skin and Language Theme: Before I address the tube, I would like to look at resistor 3. Do you see that as what should be? Page 1 of 1 You cannot start a new topic You cannot reply to this topic. Thanks for staying with me Mark.
The factory value is 68K Ohms. I’ll also give him your list and ask for his opinion as well no offense intended.
ShortScale :: View topic – Epiphone Valve Senior Combo Issues
Lately I have gone more in the acoustic direction so I haven’t really looked around for amps in a few months. Eppihone in or Sign up. They just seem to “feel” better. If it’s anything like the VJ tone wise it should kickass. My opinions are based on my personal experience. Community Forum Software by IP. Dec 31 The VS might just get me back into electric though. Anyone an idea for a quick fix?
I’ve changed the tubes, checked the heater and plate voltages and verified most all the values of the resistors, and checked most of the caps. This may be an oscillation at some stage and past this stage you get only distored signal. So, that being said, you should upgrade the following capacitors with the same values: Anyone know anything about it?
I’m just not happy with the tone now even after trying just about every mod out there. Unless you meant to leave V3 in place I can’t get a signal out with input signal attached to C13 because V3 is removed.
I do not accept any liability for anything said in the above post. I’d be interested in trying one out. You will not be disappointed. DC voltage remains steady on both plate and screen grids at and respectively with light bulb current limiter in line of the supply AC Heater voltage pin 2 or 7 referenced to ground starts at 3 VAC until standby switch is turned off, then stays steady at 2. The first triode is the first gain stage, and the vlve triode, the second Quick fix would be best.
These amps can easily be transformed into little boutique monsters that will urinate all epjphone just about any other amps in the Watt range. Previous 1 2 3 Next.
Bookmarks Bookmarks Digg del. Can I use parts of the valve senior to do this mod? Here’s the schematic again valveseniorjventura4bjpg voltages. First, you spiphone bump up all of the filter caps. As for your warnings, I know two things about amps.
Added capacitors to C24 Schmatic C23 to 47uf Removed the feedback loop wire Checked all the grounds None of these has changed the attenuation drop off at a certain level, either gain or master I realize I haven’t followed the suggestions to the letter, but did what I could with what I have What next?
Login or Sign Up. Separating the preamp from them power amp is step one. If V2 epiphine V3 are still in you’ve only eliminated the reverb. The one in your first post is not working. Next on the agenda would be the pre-amp, and gain. Is that where you meant?
Gibson Brands Forums: Valve senior Mods. – Gibson Brands Forums
I really have no idea what I’m doing, but what I’m doing seems to work. This will transform the reverb from “Out of control, Useless, Over the top” to just about the best tube driven reverb circuit you’ve ever heard. Next swapped tubes both power and PI to no avail.
AC voltage at the plate of V4 climbs steadily with the increase in volume or master volume pots to 50 VAC, then drops to 1 VAC when the volume at the load drops as would be expected of course but pin 5 of V4 rises from 0 to 8 VAC, then jumps to 9 VAC during the same test. Yes the attenuation drop off problem still occurs in that case Installed V2 and put the signal back to the input jack, virtually no output, installed V3 and problem still occurs.
And as I stated earlier, change the reverb driver tube to a 12AT7. Most people use a 10K in that application, but I’ve found that to be just a little too hot and my intention was to build a really dirty amp. Originally Posted by Urinate Forever And wiklund is smart, i’m in agreement with him.
zchematic I am using a 33K in both of my Valve Srs. I am running two 12AT7s, which draw considerably higher plate current than 12AX7s, but this has not been an issue for the power transformer sand I’ve been running both of mine very hard, for some time now. I like to use audio grade electrolytic caps when possible.