mini z

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chopstuck
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Re: mini z

Post by chopstuck »

That's 50 ma. Only good for pedals / preamps and maybe a 1 watt amp.


Flea...flea can't drive a real power tube

You need a champ / princeton style PT.

But that's just me.
Heavens, an unused PI input !
azatplayer
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Re: mini z

Post by azatplayer »

Build a champ. Much nicer amp. I owned the new model with the attenuater.
was ok for a few months, tire of it tho, just no cleans in it.
Its the amp that got me into building tho, i copied it as it was in front of me. Was a great way to explore building.
My clone sounded identical too, and started me off looking for more single ended ideas, i still have that amp in various diguise.
It IS a GA5 verbatim. And to be honest, the epi VJ i own, is nicer and has more substantial iron, better cleans too.
I built a vibrachamp that owns it imo. Alltho, caveat , if you like buzzy gain tones then its cool. It does have a cool tone, tho just the one.
collinsamps
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Re: mini z

Post by collinsamps »

If you are an el84 guy, it's possible to borrow from the Z/GA5, EVj, and few other so called 5 watters and add features like a pab boost, bright switch, low gain pre switch, etc. that will make a very versatile screamer of a single ended el84 that does have nice functional cleans for a 5 watter. I'm not knocking the champ, I think we all realize what a time proven circuit it is, but the champ circuit in stock form, even with the el84 output stage doesn't give you what you can get if you experiment a little. Also, as Vox learned a long time ago, having more ma on tap than you use in a PT actually contributes to the sound in a good way, so don't skimp on ma even if it's functional.
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M Fowler
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Re: mini z

Post by M Fowler »

I know one can't believe everything you read but. I was reading yesterday about Fender had gone with EL84 on several models between the tweed tremolux and the tolex Tremolux era.

Which amps were those?
gregarious
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Fender EL84

Post by gregarious »

Mark

http://www.kbapps.com/audio/schematics/ ... ux6g9.html

Understand it was more of an experimental variant.
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M Fowler
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Re: mini z

Post by M Fowler »

Thanks for the schematic very unusal for Fender indeed.
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Noel Grassy
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Re: mini z

Post by Noel Grassy »

collinsamps wrote:If you are an el84 guy, it's possible to borrow from the Z/GA5, EVj, and few other so called 5 watters and add features like a pab boost, bright switch, low gain pre switch, etc. that will make a very versatile screamer of a single ended el84 that does have nice functional cleans for a 5 watter. I'm not knocking the champ, I think we all realize what a time proven circuit it is, but the champ circuit in stock form, even with the el84 output stage doesn't give you what you can get if you experiment a little. Also, as Vox learned a long time ago, having more ma on tap than you use in a PT actually contributes to the sound in a good way, so don't skimp on ma even if it's functional.
Thanks for suggesting this!
I've been messing with this circuit {Harmony 413= Epiphone Valve Jr. circuit save for a tube recto & a tremolo circuit.] I have it driving two AlNiCo 8" speaks and there's a killer low end no Champ or Magnatone Varsity ever got! I'm adding a diode recto with beefier filter caps on a rotary switch to get the plates up around 250VDC next. This little bugger is light for hauling and it
almost keeps up with my heavy handed drummer's SPL.

Noel Grassy.
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collinsamps
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Re: mini z

Post by collinsamps »

Noel Grassy wrote:
collinsamps wrote:If you are an el84 guy, it's possible to borrow from the Z/GA5, EVj, and few other so called 5 watters and add features like a pab boost, bright switch, low gain pre switch, etc. that will make a very versatile screamer of a single ended el84 that does have nice functional cleans for a 5 watter. I'm not knocking the champ, I think we all realize what a time proven circuit it is, but the champ circuit in stock form, even with the el84 output stage doesn't give you what you can get if you experiment a little. Also, as Vox learned a long time ago, having more ma on tap than you use in a PT actually contributes to the sound in a good way, so don't skimp on ma even if it's functional.
Thanks for suggesting this!
I've been messing with this circuit {Harmony 413= Epiphone Valve Jr. circuit save for a tube recto & a tremolo circuit.] I have it driving two AlNiCo 8" speaks and there's a killer low end no Champ or Magnatone Varsity ever got! I'm adding a diode recto with beefier filter caps on a rotary switch to get the plates up around 250VDC next. This little bugger is light for hauling and it
almost keeps up with my heavy handed drummer's SPL.

Noel Grassy.

Very cool. I found 260 to be the sweet spot for my 5 star in terms of breakup and usable cleans. You're right about keeping up with drummers, an efficient speaker like an alnico blue makes it sound like a good 20 watts.
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roberto
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Re: mini z

Post by roberto »

I've posted some mods to doctorify the GA5, and people are always happy with them:
- 1M input impedance instead of 68k
- bright cap before the gain
- 1k5 grid stopper instead of the tonestack
- first resistor in power supply jumpered (so you have 44µ on plates)
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