1993 Fender '63 Vibroverb RI (Brown) mod suggestions

[GuitarPilot65]

Looking to replace stock output transformer with Mercury Magnetics Toneclone FBVO. Is this the correct model for this amp?


Guy I bought it from pulled the "bright" cap and replaced stock speakers with Jensen C10Q's. It's still too bright. I'm thinking of replacing these speakers with Weber 10F125s. Does anyone have experience with the Weber 10F125?

[stratomaster]

You can tame the brightness by changing

R17 to 82kΩ
C7 to 250pF

This is for the reverb/vibrato channel only.

Do small scale component swaps before dropping big money on transformers that won't end up giving you the tonal changes you're chasing.

[GuitarPilot65]

Hello. I appreciate the reply.
The previous owner removed C7 altogether. Are you saying add a 250pF back in its place?
Reverb and Vibrato are sent to both channels of the Vibroverb's 6G16 circuit. However I'll still take a look at that resistor suggestion.
Thanks!

[stratomaster]

According to the schematic I found, C7 is the treble capacitor in the tonestack.  It's currently a 330pF which increases high mids vs the 250pF cap used in Blackfaces and their derivatives. 

The Bright cap is C11

[TitaniumValhalla]

I have had those Jensen 10”s before and they are harsh and bright. You may find that model of Weber to be bright as well. You might try the Weber DT10, especially if you like amp overdrive as they are less efficient and will allow you to crank it further without blowing yourself away. The DT10 is DARK and will tame a bright amp. Might be what you’re after, and you might even be able to put the bright cap back with them.

I hope he did pull C11 and not C7, otherwise you’d have quite a bit of DC voltage on your treble pot.

[sluckey]

I hope he did pull C11 and not C7, otherwise you’d have quite a bit of DC voltage on your treble pot.

     How so?

[Latole]

I hope he did pull C11 and not C7, otherwise you’d have quite a bit of DC voltage on your treble pot.

     How so?

Yes, How so ?

[Latole]

With a MM output xfrs will the amp sound really better at your ears ?

I will check output tubes's bias first. it cost nothing

A correctly biased amp will run efficiently and maximizes the life of your tubes.
Under - biased (hot ) amps will lack of punch and tubes will run hotter , shorter tube's life .

Overbiased amps  ( cold ) will sound thin and brittle. with tubes running too cool for proper performance .
A correctly biased amps will sound clean and tight a moderate volumes, than at higher volumes breakup and distort musically .

[TitaniumValhalla]

I hope he did pull C11 and not C7, otherwise you’d have quite a bit of DC voltage on your treble pot.

     How so?

You’re right, for some reason my mind went to bypassing it, not clipping it. Carry on!

[jlaj]

Not to come across the wrong way, but have you tried the tone knob on your guitar? I’ve played some bright amps and it sometimes is a benefit because it feels like there’s a little bit more grit and I can control it with the tone knob that’s at my fingertips. I find it’s easier to do this kind of tone shaping than when changing coupling caps to block bass, or anything inside the amp.

[GuitarPilot65]

Hello, All, and thanks for the responses! Apologies, as I am just now logging back in since making my original post.


My mistake; C11 was removed, not C7.


A little more context - Back in 2007 I saw a guitarist at a club using a VV. What intrigued me was that he had a jumper lead from the Normal channel to the Bright channel, while his guitar was plugged into the other Normal channel input. When I began looking into the VV I stumbled upon this: https://waynereno.com/index.html (I applied several suggestions therein to my DRRI; it sounds phenomenal, but that's a discussion for another thread).


I was originally going to purchase a Weber 6G16 kit (which they apparently no longer offer) when I stumbled upon my VVRI. After being in storage for the past six or so years I'm rediscovering it. I just reread the seller's description (attached) and forgot he also added a bias pot.   However, unlike the external connections Mr. Reno had installed on his DRRI (as I also did on my DRRI), the chassis of my VVRI needs to be removed from the cab for bias testing. Not very practical.


Then there's the single-coil buzzing (worse when not using the grounded plug; please don't admonish me over the safety of this, as I'm well aware)


I'll post some more as I dive back into it.