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Is there a schematic available of the Tramp without the VRM components? I'd like to remove all the VRM components but I'm not sure what to remove and how to reconnect. I assume I could add a standard power OFF/ON switch where the VRM control is located. Actually, schematics of all the Trinity amps sans VRM might be useful for those who don't plan to use this feature. Thanks - Tom

The schematic shows a dotted line around the VRM parts. Eliminate them but you MAY need to increase the 100R to 1K and add a stand-by switch.

The amps don't come with VRM standard so all the schematics are sans VRM already!

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Stephen - Thanks. After removing the VRM components & adding a stand by switch, are there any wires that need to be reconnected in a different way or will the amp work just by removing the VRM components & adding the standby switch?

Also, do I need to check voltage(s) at any specific points to determine whether or not to increase the 100R resistor value to 1K? If not a voltage test, what do I need to check to determine the resistor value required after VRM removal?

Thanks a lot for your outstanding support. Tom

I have just removed the VRM from my Tramp build and added a standby switch. I left the 100ohm resistor in and I noticed my voltages went up a tad. When I installed a 1K resistor, the voltages after the resistor dropped significantly but the amp still sounded good. When I put the 100 ohm back in, the 1K resistor was very hot so I am leaving the 100 ohm in for now. I was not happy with the VRM since it distorted the sound at all settings below 8. Has anyone else had this experience with the Tramp? I did not use Tramp transformer set and instead used a Hammond P-T272BX which gives 300V on the secondaries compared to 315V on the Tramp PT which explains why my B+ voltages are about 5% below what is shown on the layout. I also used a BBQ single ended OT which matches the Tramp OT specs except that it only has 5K on the primary. Don't know if my choice of transformers is causing these problems.

Dan

To clarify things, to run the amp without the VRM circuit, I should remove the following components:
MOSFET
Diode Z1
100K 1W R21
100K R22
5 ohm 1W R20
Power level pot VR5

Is this correct? Aside from the standby switch, do I need to make any different connections or just simply remove the components above? Put another way, do I just simply yank out the components listed above and the amp will work?

Thanks for your comments Dan. Perhaps you can comment on this posting. Tom

Tom,

No. After you remove all of the VRM components, you will have to make one connection between R23 and the positive side of C12. Once you remove these components, there will be nothing connected to one side of R23. If you still have the underboard wire connected from C12 to where the zener diode and R20 connect, you can connect R23 to this point. Just run a jumper wire between the turrets to complete the connection. I did not change the value of R23 and the amp is running fine.

Installing a standby switch is a bit more involved. It has to go between where the 2 diodes connect and the plus side of C13 and R23. This will require relocating R23 and doing some additional wiring using the lugs from the VRM.

Dan

Having built a stock Tramp kit, I have not experienced distortion caused by the VRM below 8.

It is easy to get clean tones with the preamp in tweed mode with the VRM below 8. Try it with the Tweed mode at 5 or 6 and you should get a clean tone with the VRM below 8.

The Tude mode causes distortion to happen earlier, but this is normal as the additionnal preamp stage pushes the amp in the brown zone. This is what happens with single coils with my Tramp. To get amp stage distortion, I have to go to 8 or higher on the VRM.

If your guitar is humbucker equipped, then, the hotter the pickup, the faster you encounter distortion.

Hope this helps.

All my components came fron Trinity, including the transformers.

I guess I am not a fan of VRM. I tried it on one of my 5E3 builds and seemed to have the same problem. I removed it from the 5E3 and put in a master volume that is working great. Since the Tramp has a MV, I am very satisfied with the various tones I can get without the VRM. I am now using the Tramp at rehearsals and might even use it at gigs. My main gigging amp is the Lightning 15 clone I built several years ago using 2 10" BBQ Speakers (Blue Pup and Silver 10 - Alnico).

Dan

I really believe that a VRM should be installed to control only the power tube(s). A MV is installed just ahead of the o/p stage to drop the drive to the o/p stage as the B+ is dialed down. This way all the tone and dynamics of the preamp remains the same.
just my $0.02
Stew

Dan - Thanks for the VRM removal clarification, particularly on the jumper wire. Regarding the standby switch, which options have you tried or recommend. Specifically:

1-Installing a Power ON/OFF switch in the hole vacated by the VRM pot & installing a 2nd switch for Standby (another hole would need to be drilled I assume).
2- Installing a single ON/STANDBY/OFF Switch in the hole vacated by the VRM pot.

Option 2 sounds preferable since drilling a 2nd hole isn't required. If you've installed a 3 way switch, which type would you recommend (i.e. DPDT ON/OFF/ON (aka Center Off) or DPDT ON/ON/ON?)

I know some amps use Option 2 but I haven't found any info as yet on which switch type they use and how to wire it up. Thanks in advance for your expertise.

Tom

Stephen uses the on-on-on switch in his Triwatt You could have a look at the wiring in the resource section. As to where to buy one...?
Stew
viewtopic.php?f=14&t=1468

Since I built the Tramp from scratch, I had a separate on/off switch and power control. I installed the standby switch (SPST) in the hole from the power control. I would go with Stew's recommendation on using the on/on/on switch to simplify the addition of a standby. This would avoid drilling another hole.

Dan

The 3 way ON/ON/ON is a good solution, but so far I've only found them in mini-toggle style. Will do some searching and post the results.

Stephen - Will Trinity be selling the equivalent Carling switch to it's customers?

Thanks - Tom

It appears that Antique Electronics (aka CE Electronics) has a new item, Part Number P-H520, which is described as a Carling Play-Standy-Off switch. Goes for around $6.00. Here are the links.

https://secure.cedist.com/
or
https://secure.tubesandmore.com/

This is the same company - one link is for retail, the other for repair techs (lower prices). This may be the same switch that Stephen referred to for the Triwatt.

This switch would mean no drilling of an extra standby switch hole for those removing the VRM section from the Tramp or other Trinity amps with VRM's.

Tom

I've done business with these guys . Positive experience!

We tried it that way to start but in a SE amp, it doesnt work as well on the power tube only so went back to the full on power control.

I agree that the MV does an excellent job on this amp, and in the final analysis, the Tramp may loose the VRM and be replaced by a progressive switch as discussed earlier. OFF-STANDBY-ON . Then for those who want a VRM, they can add it as an option later.

Still, one of the things you could do is to introduce a Zener with a switch to drop the B+ to "Brown" out the amp or bring the voltages into the vintage Tweed zone.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Maybe I'm missing something here I dunno.

I tend to think of the VRM as another tone tweaking tool on the amp, so I'm happy with it. If you have already built your Tramp with the VRM in it wouldn't it be more convenient/easier and versatile to just leave the VRM in the amp and when playing dial it to MAX, then for standby set it at IDLE?

Wouldn't that approach essentially be the same as removing it and adding a Standby, but without doing the invasive surgery on the amp, plus you still have it there if the mood strikes to tweak the tone with it?

Snowy

Interesting!

Would you mind chiming into this thread on the 18 watt page that has some VRM questions?
http://www.trinityamps.com/phpbb/viewtopic.php?f=7&t=3010&p=25621#p25621

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Go Buckeyes!

Controlling the power tubes in our SE Amp didnt work as well as expected so went back to the full on power control.

If you still dont like it's tonal impact, do as Snowy suggested. Full on or at min for idle.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

We deliberately vary the whole amp's DC in the case of the Tramp, so that as well as reducing volume we can also get browner tones.

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Great tones come in small glass jars!