Low Powered EL84 Stereo Amplifier - How to use it for guitar?

[LooseStrings]

A friend of mine overheard me saying I would like to try a Vox amp, so next time I see him he hands me this chassis with stereo EL84 tubes (knowing I like to tinker). I believe it was once part of a stereo system and might have had a powered turntable connected to it. When I get it home I plug in some speakers and fire it up, pretty low volume. It seems there is no preamp, so I plug in a compresser and max out the level, then plug in my klon clone and up the output on that....and this thing sounds amazing. Pretty good volume too.

So... I guess the amp has no preamp. How can I fix this? Could I get a good preamp pedal? Can I build a preamp section and connect it with the poweramp? What can you recommend?

Thanks folks!

 

[Dacious]

Fitting a preamp to the chassis would be fine. It would only take 1 12AX7 and two pots to create a Tweed style like a 5F11 or 2 to make an early Vox/Marshall EL84 type amp. Mostly they came with a volume and treble cut tone control.

Or you could use a Sansamp or stomp amp signal out. Basically you need more gain and eqs. Remove negative feedback - voila.

 

[LooseStrings]

Fitting a preamp to the chassis would be fine. It would only take 1 12AX7 and two pots to create a Tweed style like a 5F11 or 2 to make an early Vox/Marshall EL84 type amp. Mostly they came with a volume and treble cut tone control.

Or you could use a Sansamp or stomp amp signal out. Basically you need more gain and eqs. Remove negative feedback - voila.

What should I look for in a Sansamp or stomp amp? Are there particular ones that would work best? Thanks!

 

[Tim S]

 

[radiocaster]

You should keep it stereo so you can use stereo effects.

Be aware that if you don't plug a speaker into each side you'll fry the OT without a speaker.

 

[printer2]

Do you have the make and model number of the stereo?

 

[Wally]

Fyi, it is not the type of power tube that makes an amp do what it does. It is the circuit that determines that. So…an EL84 amp is NOT necessarily an amp that will yield a Vox sonic.
That said, have fun with the project.

 

[archetype]

A friend of mine overheard me saying I would like to try a Vox amp, so next time I see him he hands me this chassis with stereo EL84 tubes (knowing I like to tinker). I believe it was once part of a stereo system and might have had a powered turntable connected to it. When I get it home I plug in some speakers and fire it up, pretty low volume. It seems there is no preamp, so I plug in a compresser and max out the level, then plug in my klon clone and up the output on that....and this thing sounds amazing. Pretty good volume too.

So... I guess the amp has no preamp. How can I fix this? Could I get a good preamp pedal? Can I build a preamp section and connect it with the poweramp? What can you recommend?

Thanks folks!

Put a Joyo American Sound or any similar 'character' pedal in front and it's a done deal. Use a Y adapter to drive both channels of the amp.

 

[LooseStrings]

Ok, I bought and received one of these and it is awesome. Plugged into the stereo amp it sounds great. I also plugged it in to my Hot Rod Deluxe which is just collecting dust, and also amazing. I think I may just play it that way instead of through the stereo amp. I have an attenuator on the HRD and with this AC Tone it is just a whole different beast.

 

[LooseStrings]

Put a Joyo American Sound or any similar 'character' pedal in front and it's a done deal. Use a Y adapter to drive both channels of the amp.

Just got the AC Tone. It sounds amazing.

 

[LooseStrings]

Do you have the make and model number of the stereo?

I dont see any on the chassis but there are some on the "power supplies"? Attached photo.

 

[Tim S]

Just got the AC Tone. It sounds amazing.

Glad it worked out for you

 

[W.L.Weller]

Try the AC Tone plugged into the Power Amp in of the Hot Rod Deluxe if you haven't already. But it'll also work just find plugged into the regular input. Different EQ options are always nice to have.

 

[studio]

I know ima little late to the festivities here, but my input would be to get a small mixing board and make that amp sing with the right levels on a variety of instruments!

With the right speakers, I bet even using it as a small vocal PA would be nice!

Guitar Center has their store brand lil mixers with built in fx going for peanuts these days.

I wouldn't limit it to just guitar sounds.

 

[LooseStrings]

Try the AC Tone plugged into the Power Amp in of the Hot Rod Deluxe if you haven't already. But it'll also work just find plugged into the regular input. Different EQ options are always nice to have.

Do I do the following: preamp out into the pedal input, and pedal output into the power amp in? Im not sitting by the amp at the moment but will give it a shot when I am. Thanks for the suggestion.

Oh, and by the way this is where I have my "attenuator" which is this one.

 

[W.L.Weller]

Do I do the following: preamp out into the pedal input, and pedal output into the power amp in?

That's another option, there are actually 3 choices:

1) Guitar > Hot Rod Deluxe Input 1 or 2 > Preamp Out > AC Tone > Power Amp In
2) Guitar > AC Tone > Hot Rod Deluxe Input 1 or 2 > Preamp Out > Donner > Power Amp In
3) Guitar > AC Tone > Power Amp In

I omitted the Donner from option 1 and 3 since the "Level" knob on the AC Tone will basically duplicate what the Donner is doing.

What is the Donner doing? Instead of calling it an "attenuator" (since people usually use that word to refer to a different device that goes in between the amp's speaker output and the speaker itself (absolutely do NOT use this Donner box like that)) I'd call it an "Effects Loop Master Volume". The Donner is basically a volume pedal with a hand-operated knob instead of a foot-operated treadle. (I realize that the Hot Rod Deluxe has a "Master" knob, but that's a little misleading, since the "Master" knob is really just the pre-amp Level control for the Drive and More Drive channels.

Option 1 has your signal going through the HRD pre-amp, then through the AC Tone. By way of experimentation with this setup, you could turn the "Bass" control on the HRD to 0, and then observe that the "Bass" control on the AC Tone has almost no effect on your overall sound.

Option 2 has your signal going through the AC Tone, then through the HRD pre-amp. By way of experimentation with this setup, you could turn the "Bass" control on the AC Tone to 0, and then observe that the "Bass" control on the HRD has much less effect on your overall sound than it would without the AC Tone. Almost all of the low frequencies are getting filtered out by the AC Tone before they get to the HRD pre-amp.

Option 3 skips every knob on the HRD except Reverb and Presence. All tone shaping (except the Presence setting on the HRD), gain and overall level will be controlled by the 6 knobs on the AC Tone.

If you want to add the Donner to Option 1 or 3, I'd put it right before the Power Amp In. But I suspect you'll find it's just duplicating the Level control on the AC Tone.

 

[LooseStrings]

That's another option, there are actually 3 choices:

1) Guitar > Hot Rod Deluxe Input 1 or 2 > Preamp Out > AC Tone > Power Amp In
2) Guitar > AC Tone > Hot Rod Deluxe Input 1 or 2 > Preamp Out > Donner > Power Amp In
3) Guitar > AC Tone > Power Amp In

I omitted the Donner from option 1 and 3 since the "Level" knob on the AC Tone will basically duplicate what the Donner is doing.

What is the Donner doing? Instead of calling it an "attenuator" (since people usually use that word to refer to a different device that goes in between the amp's speaker output and the speaker itself (absolutely do NOT use this Donner box like that)) I'd call it an "Effects Loop Master Volume". The Donner is basically a volume pedal with a hand-operated knob instead of a foot-operated treadle. (I realize that the Hot Rod Deluxe has a "Master" knob, but that's a little misleading, since the "Master" knob is really just the pre-amp Level control for the Drive and More Drive channels.

Option 1 has your signal going through the HRD pre-amp, then through the AC Tone. By way of experimentation with this setup, you could turn the "Bass" control on the HRD to 0, and then observe that the "Bass" control on the AC Tone has almost no effect on your overall sound.

Option 2 has your signal going through the AC Tone, then through the HRD pre-amp. By way of experimentation with this setup, you could turn the "Bass" control on the AC Tone to 0, and then observe that the "Bass" control on the HRD has much less effect on your overall sound than it would without the AC Tone. Almost all of the low frequencies are getting filtered out by the AC Tone before they get to the HRD pre-amp.

Option 3 skips every knob on the HRD except Reverb and Presence. All tone shaping (except the Presence setting on the HRD), gain and overall level will be controlled by the 6 knobs on the AC Tone.

If you want to add the Donner to Option 1 or 3, I'd put it right before the Power Amp In. But I suspect you'll find it's just duplicating the Level control on the AC Tone.

I didn't know about using the Preamp, Poweramp on the HRD like this. Very informative. I have played around with option 2 you suggested and to me it sounds amazing. The HRD has always been too muddy to me so I just never use it. I can see this setup being very useful and a much different sound than my other Fender amps (Bandmaster Reverb, 74 PR, DRRI).

Thanks again for sharing the knowledge!

 

[W.L.Weller]

The HRD has always been too muddy to me so I just never use it.

Don't forget to turn all the knobs on the amp. You're allowed to have the bass on 0 and treble on 10, if it sounds good to you. And try the bright switch at low volumes, that's what it's made for. And don't forget that the Presence control also affects the high frequency content of your sound.

You can "study" the Presence control specifically and independently from the HRD pre-amp with the setup I described as "Option 3".

And just because "people say" the Drive channel is bad doesn't make that true either. It's your amp and you can't hurt it by turning the knobs. (hurting your hearing is a different conversation)

 

[Wally]

I have a HR Deluxe IV here that is the best sounding Blues/Hot Rod Fender amp I have heard. It gets it done in all modes. Those with experience are surprised by its sound.…as am I.

 

[TwoBear]

A friend of mine overheard me saying I would like to try a Vox amp, so next time I see him he hands me this chassis with stereo EL84 tubes (knowing I like to tinker). I believe it was once part of a stereo system and might have had a powered turntable connected to it. When I get it home I plug in some speakers and fire it up, pretty low volume. It seems there is no preamp, so I plug in a compresser and max out the level, then plug in my klon clone and up the output on that....and this thing sounds amazing. Pretty good volume too.

So... I guess the amp has no preamp. How can I fix this? Could I get a good preamp pedal? Can I build a preamp section and connect it with the poweramp? What can you recommend?

Thanks folks!

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