Revoicing Normal channel on a Deluxe Reverb

[xjazzy]

I've been searching some info on amps and saw an ideia I liked: addin some "tweed" character to the Normal channel of a Deluxe Reverb (read here).

Has anyone tried some revoincing on the re-issue model?

What mods did you do and how that affected the sound?

 

[xjazzy]

Anyone?

 

[Mik]

I've never had an amp modded like that, interesting to read about though, thanks.

 

[xjazzy]

I'll give it just one more try...
Anyone?

who can I talk too about this kind of mods?

 

[Telemonger]

I did it and it sounded pretty good. There is more mids and the channel sounds fatter and a little more aggressive. It was easy and I can change it back. I guess try it and see what you think.

 

[xjazzy]

Hi telemonger.
You're talking about a original one or the re-issue?

 

[Telemonger]

An original hand-wired, no pcb. You can do it to a RI by locating the same parts and swapping values. If you're not using the Normal channel now it's worth a shot and use an A/B box.

 

[xjazzy]

That's the problem: finding the parts.
When I have some spare time I'll give it a try.

Thanks.

 

[Telemonger]

You can get the parts from Mouser electronics or Small Bear Electronics. Small Bear is easier to order with because you do not have to go through thousands of catalog parts to find what you need. Fast shipping as well.

 

[Martin R]

Is all that needed?

I use an A/B box with my '65 Deluxe, (no reverb). The vibrato channel is used mostly for rhythm, Treble at 7, Bass 6. The normal channel is for leads and usually set about a half point higher than the normal, with tone controls dimed. I've also got a 12AT7 in the normal side.

Seems to give me a little boost and fuller tone for leads, just by tapping my toe, (when I can find the damn pedal...it's the one that never seems to stay put on the board).

I do like idea of the pot on the phase inverter. It'd be great for recording.

 

[xjazzy]

I've tried different tubes in the position V1 but I never liked the result.
I would love to get some more punch and grit from the normal channel.

 

[jhundt]

I have tried changing all those tone-stack components before. Fender used a few different combinations, if you study the schematics for the various black- and silverface amps you will see...

I really couldn't hear much (or any) difference. I'm sure there is some change, but my ears couldn't distinguish it.

I think if you want a truly different voice on the Normal you would do better to lift the ground at the 6800 mid resistor. This disables the tone circuit and adds a lot of gain and mid-range. It gives a sound somewhat more like the tweed amps. It is easy to do, 100% reversible - and if you choose you can make the ground-lift switchable so you still have a normal Normal should you require it.

 

[xjazzy]

jhundt, I liked that idea.
I'll try it... when I find where's that resistor! Do you know its position on the circuit?

 

[Telemonger]

I have tried changing all those tone-stack components before. Fender used a few different combinations, if you study the schematics for the various black- and silverface amps you will see...

I really couldn't hear much (or any) difference. I'm sure there is some change, but my ears couldn't distinguish it.

I think if you want a truly different voice on the Normal you would do better to lift the ground at the 6800 mid resistor. This disables the tone circuit and adds a lot of gain and mid-range. It gives a sound somewhat more like the tweed amps. It is easy to do, 100% reversible - and if you choose you can make the ground-lift switchable so you still have a normal Normal should you require it.

That's a totally cool mod and the most noticeable of them all. It makes the channel really breath fire. Put it on a footswitch and you have a really cool gain boost. You can even wire the switch with an LED for annunciation and power it with a 9v battery and also have a jack to hook up to your pedalboards power supply. Cool....

 

[Wally]

Yes, those cap changes to the .022mfds will emphasize some mids in the channel and remove some of the tendency to get flabby on the low end. I have never gone to a 220K for the slope resistor. I have gone to a 56K....that definitely is more of a Marshall thing.
I also like to separate the cathodes of V1 and V2. This allows you to manipulate the gain in the two channels independently. You can heat up the Normal channel while keeping the Vib ch stock.
The negative feedback change is soemthing I like....I would rather have a potentiometer to go from stock resistance(820 ohms) to a much larger resistance. I have measured
22K as a point at which one player liked things.

 

[ojaverde]

I think if you want a truly different voice on the Normal you would do better to lift the ground at the 6800 mid resistor. This disables the tone circuit and adds a lot of gain and mid-range. It gives a sound somewhat more like the tweed amps. It is easy to do, 100% reversible - and if you choose you can make the ground-lift switchable so you still have a normal Normal should you require it.


I have a 64 non reverb Deluxe. Will lifting the ground on the 6800 bass resistor acomplish the same thing?

 

[Martin R]

I have a 64 non reverb Deluxe.

You're the only person I've ever come across with another non-reverb Deluxe...We could start a club and have meetings in Buick.

Martin
http://EChristinaHerr.com

 

[chabby]

Its a huge part of what I do to SF fenders especially - its almost a waste not to tweed or marshallize the non vibrato side even if the amp is collectible - just change it back if you want to sell.

 

[xjazzy]

Its a huge part of what I do to SF fenders especially - its almost a waste not to tweed or marshallize the non vibrato side even if the amp is collectible - just change it back if you want to sell.

You're talkiing about the mod from the first post, right?

My problem is finding the parts to change on the PCB of the DRRI!

 

[jhundt]

I'll try it... when I find where's that resistor! Do you know its position on the circuit?

If you're looking at the amp chassis from the back, the Bass control for the Normal channel is the third pot from the right. The 6800 resistor jumps from the 3rd tab of that pot to the back of the pot (which is a ground). You can simply desolder the terminal and disconnect the resistor at that end, leaving the resistor connected at the back of the pot. There is also a blue(?) wire at this terminal - just leave that connected.

If you want to add a switch, just run a wire from the terminal to one side of a single-pole single-throw (SPST) switch; Bring another wire from the other side of the switch back to the free end of the 6800 resistor. Now you can use the channel either way - as originally wired or with the tone circuit disabled.

I have a 64 non reverb Deluxe. Will lifting the ground on the 6800 bass resistor acomplish the same thing?

Yes. Lifting the ground from the tone-stack will work on most black and silverface Fenders. I won't say ALL because there may be some exceptions that I can't recall.

I have my Princeton Reverb II wired this way. The tone is much more aggresive with the ground lifted, and quite a bit louder too.