Hey all, well I have been in the basement reading all about how tubes work...still need to learn more :>) Currently I'm restoring a console type amp with EL84's. But I think I'm almost at the point of building one...or two :>)
My question is, I have a box full of Luxman EL34's (never used and still in boxes) as well as a box full of ECC83's (never used). I feel I should be doing something with these. Anyone know of a good design to build? Nothing large, just a simple but awsome sounding amp to drive a pair of 2-way bookshielfs, DIY of corse.
Man are tubes fun!
Rino Odorico
My question is, I have a box full of Luxman EL34's (never used and still in boxes) as well as a box full of ECC83's (never used). I feel I should be doing something with these. Anyone know of a good design to build? Nothing large, just a simple but awsome sounding amp to drive a pair of 2-way bookshielfs, DIY of corse.
Man are tubes fun!
Rino Odorico
SHOEBOXES
Hi,
In case you want to put your tubes to good use:
The CR syblos are there to indicate NFB loops of which there 3 local ones and 1 global.
As far as the PSU goes you could use a tubed or one using silicon diodes.
I'll mail the daigrams with examples to Dave since I can't seem to attach a file.
Cheers,
Hi,
In case you want to put your tubes to good use:
The CR syblos are there to indicate NFB loops of which there 3 local ones and 1 global.
As far as the PSU goes you could use a tubed or one using silicon diodes.
I'll mail the daigrams with examples to Dave since I can't seem to attach a file.
Cheers,
OTL with EL34s? Naah. Bad choice.
Keep it simple. Get a 6600 ohm p-p OP anchor, use a simple input circuit (like a triode voltage amp direct coupled to a long-tail inverter- the Eico HF87 circuit is a classic), use a simple power supply. I'd avoid the silicone that Frank suggests- it's too jiggly. But silicon rectifiers will work.
Joe Curcio's ST-70 circuit is a good one, too. I used his input stage and regulator to drive '34s wired as triodes with good success.
Keep it simple. Get a 6600 ohm p-p OP anchor, use a simple input circuit (like a triode voltage amp direct coupled to a long-tail inverter- the Eico HF87 circuit is a classic), use a simple power supply. I'd avoid the silicone that Frank suggests- it's too jiggly. But silicon rectifiers will work.
Joe Curcio's ST-70 circuit is a good one, too. I used his input stage and regulator to drive '34s wired as triodes with good success.
Now both those circuits have too many ECC83s in them for my taste (i know you have new ECC83s -- what kind, on eBay they may fetch enuff to pay for the iron -- especially if they have little diamonds on the bottom).
Here is what i'm going to base my Dyna ST70 on:
this schema and a couple accompanying ones (and a picture) can be found at the http://www.vacuumstate.com/schematics.htm]Vacuum State[/URL] web site (you will have to scroll down a bit.
dave
Here is what i'm going to base my Dyna ST70 on:
An externally hosted image should be here but it was not working when we last tested it.
this schema and a couple accompanying ones (and a picture) can be found at the http://www.vacuumstate.com/schematics.htm]Vacuum State[/URL] web site (you will have to scroll down a bit.
dave
CHEVEUX BOUCLES.
Hi,
Correct,only I didn't want to chop of the circuit part since it may be usefull to others.
Naturally it will need some mods to work with the first circuit and I'd put some bigger caps behind the chokes.
This one circuit that benefit from the brute force approach especially when crossing to Class B operation.
Sy,
Charmant,no?
All,
If anyone needs a translation of the french text under that first circuit I'll be happy to do it.
Cherio,
Hi,
Correct,only I didn't want to chop of the circuit part since it may be usefull to others.
Naturally it will need some mods to work with the first circuit and I'd put some bigger caps behind the chokes.
This one circuit that benefit from the brute force approach especially when crossing to Class B operation.
Sy,
Charmant,no?
All,
If anyone needs a translation of the french text under that first circuit I'll be happy to do it.
Cherio,
Hey, talk about info!
Wow, thanks guys! And the circuits don't look that bad to build! Now, just to choose which one to do...
As far as the tubes...been a while since I looked. From what I can remember about the ECC83's, they are not "Matched" or in any order. Darn can't remember what make. Put it to ya this way, I have approx 20 of them. They actually can from Luxman Canada's service depo.
The EL34's approx. 15-20. I know that those are not in matched pairs. What make are they, well they say Luxman directly on them...so who ever they used back then.
Frank, never seen anything like that pre-stage before...4 tubes?
Rino Odorico
Wow, thanks guys! And the circuits don't look that bad to build! Now, just to choose which one to do...
As far as the tubes...been a while since I looked. From what I can remember about the ECC83's, they are not "Matched" or in any order. Darn can't remember what make. Put it to ya this way, I have approx 20 of them. They actually can from Luxman Canada's service depo.
The EL34's approx. 15-20. I know that those are not in matched pairs. What make are they, well they say Luxman directly on them...so who ever they used back then.
Frank, never seen anything like that pre-stage before...4 tubes?
Rino Odorico
MATCH
Hi Rino,
Actually what you see are just two 12AX7As',each contains two triodes that should be matched already internally.
The diagram you see is very well thought out and is known to be able to drive even difficult loads with ease.
The EL34s' should be matched for optimum performance.
Maybe ask a dealer to do that for you against a nominal fee?
Yur Lux tubes are likely to be Japanese jobs built by Matushita,NEC or Toshiba depending on age.
Sy,
Mon ami,you izz wrong in yourrrr assumption.
Je suis Flemish,and proud of it.
Fact is most Flems do speak French whereas very little Wallons speak Flemish.
Put a Wallon and a Flemish guy together and within a second or two they'll speak in french to each other,never,never the other way around.
Cheers,
Hi Rino,
Actually what you see are just two 12AX7As',each contains two triodes that should be matched already internally.
The diagram you see is very well thought out and is known to be able to drive even difficult loads with ease.
The EL34s' should be matched for optimum performance.
Maybe ask a dealer to do that for you against a nominal fee?
Yur Lux tubes are likely to be Japanese jobs built by Matushita,NEC or Toshiba depending on age.
Sy,
Mon ami,you izz wrong in yourrrr assumption.
Je suis Flemish,and proud of it.
Fact is most Flems do speak French whereas very little Wallons speak Flemish.
Put a Wallon and a Flemish guy together and within a second or two they'll speak in french to each other,never,never the other way around.
Cheers,
Great!
Great, should have known...as per the reading I have been doing..."some triodes will actually be doubled internaly" or something like that (can't remember the words perfectly, but I get the jist).
Looks like a great starter amp Frank. Hate to bother you about it, but when I print it...can't really read it very well. Could you if possible (please) e-mail it to me? Now here's the topper...and anything else you have on it?
rodorico@ca.telus.com 
Great, should have known...as per the reading I have been doing..."some triodes will actually be doubled internaly" or something like that (can't remember the words perfectly, but I get the jist).
Looks like a great starter amp Frank. Hate to bother you about it, but when I print it...can't really read it very well. Could you if possible (please) e-mail it to me? Now here's the topper...and anything else you have on it?
rodorico@ca.telus.com
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