VVR in a "beefed up" 5E3 Tweed Deluxe (FINISHED)

[angelodp]

Ken, just a thought.... have you considered an airbrake, simple build. I have the VVR in my Rocket and I built the Airbrake, between the two I can dial in a perfect level for my small studio or a larger space. I use the airbrake on my Mission kit 5E3 and it works very well.

best Ange

[doveman]

I really like the idea of the one knob VVR built into the amp. I think I've figured out what I want to do in the preamp to allow for the VVR. If I can just figure out where the actual VVR unit should go in the Supra-Luxe model, I'll install it and give it a try. I thought that was going to be the simple part ... but the power supply is a bit different from Dana's instructions.

I have a question into Dana ... hopefully he can point me in the right direction.

[angelodp]

I have read where some have tried just the power section and eventually go to the whole amp.

[IMG:900:675]http://i260.photobucket.com/albums/ii9/ ... -pic-6.jpg[/img]
[IMG:900:675]http://i260.photobucket.com/albums/ii9/ ... -pic-4.jpg[/img]
[IMG:900:675]http://i260.photobucket.com/albums/ii9/ ... -pic-1.jpg[/img]

[doveman]

OK ... I did it ... VVR whole amp ... on a beefed up (30w 6L6) Richter Supra-Luxe 5E3

Sara (Richter Amps) and Dana (VVR from Hall Amplification) have been helping me understand what needs to be done to put VVR (Variable Voltage Regulation) on the 5E3 Supra-Luxe. Both have helped me understand what is going on and checked my work a bit. Granted, I have one of the few Supra-Luxe "head format" amps ... so this may not help anyone specifically. What I think it can do is take some of the mystery out of the VVR process. What this VVR thing does is allow me to drop the voltage to the whole amp ... reducing the 30w to maybe 3w.

I have a drawing that Sara developed with the help of Dana ... me acting as a conduit back and forth while I was learning. The method I'm using is "one knob scales the whole amp" for a cathode biased amp (Supra-Luxe is cathode biased). Here is Sara's drawing ... adjusted to the Supra-Luxe ... based on the initial drawing from Dana ...
[IMG:539:639]http://i104.photobucket.com/albums/m168 ... a-Luxe.jpg[/img]

Here's what the amp looks like to start with ...
[img:639:478]http://i104.photobucket.com/albums/m168 ... CN1099.jpg[/img]

Step 1: Drill a hole in the back panel ... mount the POT/BOARD ASSEMBLY. Be sure to protect all the amp parts from shavings ... I used aluminum foil and tape. Made it easy to collect all of the shavings once done.
[img:639:478]http://i104.photobucket.com/albums/m168 ... ed01-1.jpg[/img]

Step 2: Lift the RED wire ... output to the OUTPUT TRANSFORMER off the board
[img:639:478]http://i104.photobucket.com/albums/m168 ... weed07.jpg[/img]

Step 3: Lift the 5W 4.7k resistor out ... Sara suggested that I switch it to a new type they are now using ... better quality and has a thicker lead (I need that in a later connection in Step 5):
[img:639:478]http://i104.photobucket.com/albums/m168 ... weed08.jpg[/img]

Step 4: Connect yellow and blue wires per the drawing to the B+IN and B+OUT per the drawing. Run the other end of these wires along the underside of the board. Now it the board had one more additonal hole in it ... that would be ideal but I wire tied and shrink wrapped the right side of the 5W resistor ... it is pretty stable.
[img:639:478]http://i104.photobucket.com/albums/m168 ... weed09.jpg[/img]

Step 5: Replace the new 5W 4.7k resistor (one end reattaches to board ... other end attaches to RED OT lead + Blue B+OUT lead)
Step 6: Yellow lead from the B+IN drops in to the other side ... where the 4.7k used to connect ... it doesn't now.
[img:639:478]http://i104.photobucket.com/albums/m168 ... weed10.jpg[/img]

Step 8: This was only necessary for me due to space constraints but I asked Dana and he said it was OK. If you have the space the MOSFET can attach directly to the board ... but you have to attach it to the chassis for the heat sinking of the MOSFET. I prepared some leads and connected them to the MOSFET.
[img:639:478]http://i104.photobucket.com/albums/m168 ... weed11.jpg[/img]

Step 9: Attach these MOSFET leads to the VVR board. These are the ORANGE/PURPLE/YELLOW leads twisted together in my amp.
Step 10: Attach the GROUND from the VVR board to the chassis ... this is the WHITE/BLACK striped lead in my amp.
[img:478:639]http://i104.photobucket.com/albums/m168 ... weed12.jpg[/img]

Step 11: Drill a hole in the chassis to attach MOSFET. (IMPORTANT: Must use silicon insulator (see the trasnparent square beneath the MOSFET in the picure) and this one can use a regular nut/bolt. Protect the amp once again ... this ones a bit easier ... vacuum to be sure.
[img:478:639]http://i104.photobucket.com/albums/m168 ... weed02.jpg[/img]

Step 12: One "chicken head" knob controls the whole amp level. For those familiar with the tweed 2-4-6-8-10 5E3 volume control settings, this is where I've been running this amp all day long ... with really good sounds.
[IMG:639:478]http://i104.photobucket.com/albums/m168 ... CN1125.jpg[/img]

Now one problem that Dana mentioned ... when you dial the amp back (mine at about 30%) you begin to get scratchy guitar pots as the voltage drops. There are a couple of resistor and cap adjustments you can make that will correct this. I wanted to leave the amp as close to standard as I could. While playing today, I discovered that as long as there is ONE pedal that is NOT true bypass (in other words ... with buffer), the scratchy pot disappears throughout the entire VVR range. It doesn't matter if that pedal is engaged or not ... mine is a TS9. I will run a couple of drive pedals in front of this rig so ... no issue for me. Works great ... really saisfied ... if I were not planning on running any pedals, I'd have a bit more work to do to get the scratchy pots adjusted but all of those adjustments are explained in Dana's VVR instructions.

Also, not related to the VVR but while I had the hood up, I changed the .1uf/600v caps in the pre-amp to .022uf/600v for normal channel and .047uf/600v for bright channel. Sara thought this might de-emphasize the bass a little with my humbuckers ... the standard 5E3 can be a little bassy. It also allows me to vary the bass a bit when mixing the two interactive volume controls. And ... with the extra headroom of the 30w 6L6 format in the Supra-Luxe, I've found that I like the 12AX7 in V1 ... changed that early on.

I can't tell how much help both Sara (Richter Amps) and Dana (Hall Amplification) have been as I've learned about this subject and this amp. Great to put up with all my questions.

Clips soon ... but pleased with it all.

[Structo]

Great tutorial as usual Ken.

Do you have a layout that is bigger than the one posted?
It is blurry on my monitor when I click on it and I am unable to read the text and values.

Looks like a very clean installation!

[doveman]

CLEAN CLIP ...

This is the first clip ... Vol1=0, Vol2=2, Tone=8 (VVR 100%, 50%, 25%, Almost Nothing) Tele on middle pickup ... full volume, full tone, straight in to amp.

http://soundclick.com/share?songid=8976506

I'll load up a couple of varieties to show the tone ... forgive the playing ... it's just to see if the Richter Supra-Luxe loses anything from the VVR.

[doveman]

Update: Still real happy with this VVR installation. Did learn a bit more about the scratchy pot mod. If you recall, I discovered that if I had one drive pedal that was NOT true bypass before the amp, I did not have the scratchy pot.

Here's what I learned from Dana. He pointed out that my buffered pedal now gets the effect. Sure enough if I adjust the volume level on the pedal it does it too. That would not be a problem in that I would not be adjusting the pedal volume during a song. It also explains why the true bypass pedals react the way they do ... they just pass along the "grid leak" to the guitar pots. He also explained to me that it's a nussance rather than a problem. No risk to people or equipment ... but it causes the same sound that you would have if you had a really scratch volume pot on your guitar. Bad news is that would drive someone crazy ... including me.

He has a mod in his instuctions to fix this ... moving a 1meg resistor and adding a cap before the preamp, then adding another 1meg and cap after the first preamp tube. OR you can change those two 100k resistors to 220k. You don't have to do both. The first option takes care if the scratchy pots. The 2nd option just limits how far you can dial the VVR down ... which limits the problem but also limits the VVR effectiveness. I like dialing it way down if I like (see clip above).

Nice product

[angelodp]

Ken, clips sound great. I am wondering about your test. My take on the VVR is that its meant to help take your volume down while retaining tone. I am curious as to how the amp sounds as you vary the amps volume and then dial back the VVR.

ange

[doveman]

The test I did was keep the amp at a certain setting ... in this case clean. Then drop the volume an see if it stays the same. I increased the recording volume which gives you a good idea if the tone changes. I plan on making a couple of other recordings showing what the amp sounds like cranked up with some overdrive and do the same thing. I think changing the two at the same time would not tell you much. I just ran out of time last weekend. Maybe this weekend I will pick up a few more examples.

[angelodp]

Ok, I did not catch that aspect, now it makes sense. Given that you simply used the record volume to stay in the notch it is a great test. I am still curious to hear the amp cranked up a bit and then dialed back on the VVR.

cheers ange

[UR12]

Great clips and documentation! I think you will find that adding the extra caps and resistors to correct the scratchy pot thing is well worth the effort for your sanity. Thanks For posting the clips and tutorial.

[doveman]

I think you will find that adding the extra caps and resistors to correct the scratchy pot thing is well worth the effort for your sanity.

I think you are right ... it would give me the most flexibility. The amp does sound good going straight in to it. I sent you pictures of what I think I need to do via email. If you agree, I'll take a shot at finishing this thing off. I'll post those results, as well. I think I'm close to being complete. It really does sound good ... w/o the scratchy pots ... brilliant!

[doveman]

OK I fixed the scratchy pot deal on the VVR by:

• Clipping out the 1meg resistors on the input jacks on both normal channel and bright channel.
• Added .022uf/600v and both sides of the pre-amp tube - the cap value matches the pair of .022uf caps on the board. Then added 1meg resistor to ground off the pins (these are pins 2 and 7).
• Added .047uf/600v between the volume pot and the phase inverter tube - the cap value matches the pair of .047uf caps on the board. Then added 1meg resistor to ground off pin 2 on the phase inverter.

Step 1: Add the terminal strips to both the preamp and phase inverter tubes.
[img:639:478]http://i104.photobucket.com/albums/m168 ... atchy2.jpg[/img]

Step 2: Disconnect the leads to pins 2 & 7 of preamp tube and pin 2 of phase inverter. Then add the 1meg resistors. They are grounded to the socket base through the terminal strips.
[img:639:478]http://i104.photobucket.com/albums/m168 ... atchy4.jpg[/img]

Step 3: Attach the wires to the terminals ... then caps to the pins on the tubes ... .022uf for the pre-amp ... .047uf for the phase inverter. These are the same values I replaced on the board ... replacing the .1uf all four were originally.
[img:639:478]http://i104.photobucket.com/albums/m168 ... atchy1.jpg[/img]

Scratchy pots are gone ... hopefully I haven't trashed the look of Sara's amp too much. But I'm happy with it. The VVR is wonderful too. The Supra-Luxe is far less bassy and more to my taste plus I can dial it down to nothing with the VVR without changing the tone.

[doveman]

Double post.

[Structo]

That's great Ken.
Do you feel the mods you did affected the tone negatively in any way?

I guess I thought the fix would be simpler than that, like just a cap on the input to block the DC from your guitar volume pot.