Form@C wrote:

I'm just experimenting with a source-follower single-ended MOSFET
headphone amp, with an op-amp voltage gain stage. Its rather good but not
enough output (yet!) for speakers. :-)


You could always try a gainclone

http://home.student.utwente.nl/f.s.b...rtedLM3875.gif

--
Nick

On Fri, 19 Dec 2003 18:35:41 +0000, Nick Gorham wrote:

Form@C wrote:

I'm just experimenting with a source-follower single-ended MOSFET
headphone amp, with an op-amp voltage gain stage. Its rather good but not
enough output (yet!) for speakers. :-)


You could always try a gainclone


http://home.student.utwente.nl/f.s.b...rtedLM3875.gif

I *could*, but I rather like the look of something like this:
http://digilander.libero.it/essentia...ybrid_home.htm
'cos I suspect it has more chance of *really* sounding good, rather than
being based around a chip being used for other than its designed purpose!
(ducks down behind 0.2C/W heatsinks to hide from gaincloners hurling
flaming 1000uF capacitors...)

:-)

--
Mick
http://www.nascom.info for Nascom & Gemini information
Also at http://www.mixtel.co.uk where the collection started.
Currently deserting M$ for linux... :-)

Form@C wrote:

On Fri, 19 Dec 2003 18:35:41 +0000, Nick Gorham wrote:


Form@C wrote:

I'm just experimenting with a source-follower single-ended MOSFET
headphone amp, with an op-amp voltage gain stage. Its rather good but not
enough output (yet!) for speakers. :-)


You could always try a gainclone



http://home.student.utwente.nl/f.s.b...rtedLM3875.gif

I *could*, but I rather like the look of something like this:
http://digilander.libero.it/essentia...ybrid_home.htm
'cos I suspect it has more chance of *really* sounding good, rather than
being based around a chip being used for other than its designed purpose!
(ducks down behind 0.2C/W heatsinks to hide from gaincloners hurling
flaming 1000uF capacitors...)

:-)


Well you could try this then

http://www.petemoore.pwp.blueyonder....rschematic.jpg

I didn't see the need as the one I built was being fed by a valve stage
anyway. They are fun things, I was quite shocked just how good they are
for £30. Of course you could go to the other extreme.

http://www.lurcher.org/nick/audio/vi...ul/v4212-1.jpg

:-)

--
Nick

On Sat, 20 Dec 2003 11:34:40 +0000, Nick Gorham wrote:

snip

Well you could try this then

http://www.petemoore.pwp.blueyonder....rschematic.jpg

I didn't see the need as the one I built was being fed by a valve stage
anyway. They are fun things, I was quite shocked just how good they are
for £30. Of course you could go to the other extreme.


Now - there's an idea.... :-)


http://www.lurcher.org/nick/audio/vi...ul/v4212-1.jpg

:-)

I'm *really* jealous now... I've always wanted a pair of 211s to play
with! (with the appropriate ironmongery that is!). :-)

That's a hell of a setup! (plus obligatory !!!!!! courtesy of ebay)
I particularly like the king-size timber & ply chassis system....

--
Mick
http://www.nascom.info for Nascom & Gemini information
Also at http://www.mixtel.co.uk where the collection started.
Currently deserting M$ for linux... :-)

Form@C wrote:
On Sat, 20 Dec 2003 11:34:40 +0000, Nick Gorham wrote:

snip

Well you could try this then

http://www.petemoore.pwp.blueyonder....rschematic.jpg

I didn't see the need as the one I built was being fed by a valve stage
anyway. They are fun things, I was quite shocked just how good they are
for £30. Of course you could go to the other extreme.



Now - there's an idea.... :-)



http://www.lurcher.org/nick/audio/vi...ul/v4212-1.jpg

:-)


I'm *really* jealous now... I've always wanted a pair of 211s to play
with! (with the appropriate ironmongery that is!). :-)

That's a hell of a setup! (plus obligatory !!!!!! courtesy of ebay)
I particularly like the king-size timber & ply chassis system....

Sadly not mine, and no its not at 211, its a 212 (and assorted
variants). one day I may get to play with toys like that, but first
stage 6em7.

For comparison, this pic is a ecc83 on the left, the next is a 211, and
then various 212 (ish) valves, Paul would go into great and interesting
depth about the differences. And under them all a GM100.

http://www.lurcher.org/nick/audio/vi...l/v4212-20.jpg

--
Nick

On Sat, 20 Dec 2003 22:03:11 +0000, Nick Gorham wrote:

snip

Sadly not mine, and no its not at 211, its a 212 (and assorted
variants). one day I may get to play with toys like that, but first
stage 6em7.

For comparison, this pic is a ecc83 on the left, the next is a 211, and
then various 212 (ish) valves, Paul would go into great and interesting
depth about the differences. And under them all a GM100.

http://www.lurcher.org/nick/audio/vi...l/v4212-20.jpg


wow! That is serious glassware...

I assume that the GM100 isn't for a preamp then.... Sheesh! :-)

Much as I love Paul's collection of heavy-duty audio, It can only be
regarded as an interesting conversation piece when installed like that. It
doesn't exactly blend in with the decor does it? grin
Lovely - my Mrs would kill me... Especially now I've found this pic:
http://www.lurcher.org/nick/audio/vi...paul/paul1.jpg

I've dug my old 6L6 p-p project out again. I may just get to complete it
soon! My nasty little parallelled ECC82 p-p amp still runs nicely, but
there is a bit of a hum on one channel that needs looking at. Low power,
but interesting; and a lot cooler and lighter than a 212 collection. Takes
less juice in total than the heater on one of those...
(photos on mixtel site under Rough Audio).

--
Mick
http://www.nascom.info for Nascom & Gemini information
Also at http://www.mixtel.co.uk where the collection started.
Currently deserting M$ for linux... :-)

Form@C wrote:

I assume that the GM100 isn't for a preamp then.... Sheesh! :-)

There was a actual working amp using them at VSAC

http://img.audioasylum.com/cgi/i.pl?...f=MVC-001F.JPG


Much as I love Paul's collection of heavy-duty audio, It can only be
regarded as an interesting conversation piece when installed like that. It
doesn't exactly blend in with the decor does it? grin
Lovely - my Mrs would kill me... Especially now I've found this pic:
http://www.lurcher.org/nick/audio/vi...paul/paul1.jpg


Its still a work in progress, he does have plans to make it into two
monoblocks, that can be put in the back of a van.

I've dug my old 6L6 p-p project out again. I may just get to complete it
soon! My nasty little parallelled ECC82 p-p amp still runs nicely, but
there is a bit of a hum on one channel that needs looking at. Low power,
but interesting; and a lot cooler and lighter than a 212 collection. Takes
less juice in total than the heater on one of those...
(photos on mixtel site under Rough Audio).


As I said, I have yet to build a SE amp, but after hearing the amps in
the pictures, I am going to give it a try, there was a nice sounding
6em7 amp there, (sort of rat amp construction), so I am going to give
that a try in the new year.

http://www.lurcher.org/nick/audio/vi...ul/v6em7-1.jpg

--
Nick

Form@C wrote:

I assume that the GM100 isn't for a preamp then.... Sheesh! :-)

There was a actual working amp using them at VSAC

http://img.audioasylum.com/cgi/i.pl?...f=MVC-001F.JPG


Much as I love Paul's collection of heavy-duty audio, It can only be
regarded as an interesting conversation piece when installed like that. It
doesn't exactly blend in with the decor does it? grin
Lovely - my Mrs would kill me... Especially now I've found this pic:
http://www.lurcher.org/nick/audio/vi...paul/paul1.jpg


Its still a work in progress, he does have plans to make it into two
monoblocks, that can be put in the back of a van.

I've dug my old 6L6 p-p project out again. I may just get to complete it
soon! My nasty little parallelled ECC82 p-p amp still runs nicely, but
there is a bit of a hum on one channel that needs looking at. Low power,
but interesting; and a lot cooler and lighter than a 212 collection. Takes
less juice in total than the heater on one of those...
(photos on mixtel site under Rough Audio).


As I said, I have yet to build a SE amp, but after hearing the amps in
the pictures, I am going to give it a try, there was a nice sounding
6em7 amp there, (sort of rat amp construction), so I am going to give
that a try in the new year.

http://www.lurcher.org/nick/audio/vi...ul/v6em7-1.jpg

--
Nick

On Sat, 20 Dec 2003 22:03:11 +0000, Nick Gorham wrote:

snip

Sadly not mine, and no its not at 211, its a 212 (and assorted
variants). one day I may get to play with toys like that, but first
stage 6em7.

For comparison, this pic is a ecc83 on the left, the next is a 211, and
then various 212 (ish) valves, Paul would go into great and interesting
depth about the differences. And under them all a GM100.

http://www.lurcher.org/nick/audio/vi...l/v4212-20.jpg


wow! That is serious glassware...

I assume that the GM100 isn't for a preamp then.... Sheesh! :-)

Much as I love Paul's collection of heavy-duty audio, It can only be
regarded as an interesting conversation piece when installed like that. It
doesn't exactly blend in with the decor does it? grin
Lovely - my Mrs would kill me... Especially now I've found this pic:
http://www.lurcher.org/nick/audio/vi...paul/paul1.jpg

I've dug my old 6L6 p-p project out again. I may just get to complete it
soon! My nasty little parallelled ECC82 p-p amp still runs nicely, but
there is a bit of a hum on one channel that needs looking at. Low power,
but interesting; and a lot cooler and lighter than a 212 collection. Takes
less juice in total than the heater on one of those...
(photos on mixtel site under Rough Audio).

--
Mick
http://www.nascom.info for Nascom & Gemini information
Also at http://www.mixtel.co.uk where the collection started.
Currently deserting M$ for linux... :-)

Form@C wrote:
On Sat, 20 Dec 2003 11:34:40 +0000, Nick Gorham wrote:

snip

Well you could try this then

http://www.petemoore.pwp.blueyonder....rschematic.jpg

I didn't see the need as the one I built was being fed by a valve stage
anyway. They are fun things, I was quite shocked just how good they are
for £30. Of course you could go to the other extreme.



Now - there's an idea.... :-)



http://www.lurcher.org/nick/audio/vi...ul/v4212-1.jpg

:-)


I'm *really* jealous now... I've always wanted a pair of 211s to play
with! (with the appropriate ironmongery that is!). :-)

That's a hell of a setup! (plus obligatory !!!!!! courtesy of ebay)
I particularly like the king-size timber & ply chassis system....

Sadly not mine, and no its not at 211, its a 212 (and assorted
variants). one day I may get to play with toys like that, but first
stage 6em7.

For comparison, this pic is a ecc83 on the left, the next is a 211, and
then various 212 (ish) valves, Paul would go into great and interesting
depth about the differences. And under them all a GM100.

http://www.lurcher.org/nick/audio/vi...l/v4212-20.jpg

--
Nick