Home |
Search |
Today's Posts |
#81
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
"Don Pearce" wrote in message ... On Sun, 20 Dec 2009 12:22:40 +0000 (GMT), Jim Lesurf wrote: I guess designers of commercial audio amps back then were more habituated to using transformers than nowdays. I didn't know about the above, but recall that some early domestic transistor amps included things like coupling transformers. How about a current guitar practice amplifier? http://www.soundthoughts.co.uk/look/pignose.jpg The idea is to sound like a proper valve guitar amplifier, and it sort of does it. The Pignose is brilliant. I have one. http://www.kolumbus.fi/iain.churches/Pics/Pignose.jpg A huge sound from a tiny amp:-) Iain |
#82
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
On Sun, 20 Dec 2009 18:17:48 +0000 (GMT), Jim Lesurf
wrote: In article , Don Pearce wrote: On Sun, 20 Dec 2009 12:22:40 +0000 (GMT), Jim Lesurf wrote: I guess designers of commercial audio amps back then were more habituated to using transformers than nowdays. I didn't know about the above, but recall that some early domestic transistor amps included things like coupling transformers. How about a current guitar practice amplifier? http://www.soundthoughts.co.uk/look/pignose.jpg The idea is to sound like a proper valve guitar amplifier, and it sort of does it. The transformers look quite small. What's the scale of the picture? I did once do a 'theoretical' design using two bipolars and couple of transformers to make a SET power amp, just to work out what kind of gain, etc, you might get. But never built it as it didn't seem worth trying to get suitable transformers. Maybe the above did it anyway? :-) Slainte, Jim The whole thing is small - the long side is about three inches. This is a battery powered amplifier that sees a lot of use in studios. It sounds "big" when recorded. d |
#83
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
On Mon, 21 Dec 2009 17:27:20 +0200, "Iain Churches"
wrote: "Don Pearce" wrote in message ... On Sun, 20 Dec 2009 12:22:40 +0000 (GMT), Jim Lesurf wrote: I guess designers of commercial audio amps back then were more habituated to using transformers than nowdays. I didn't know about the above, but recall that some early domestic transistor amps included things like coupling transformers. How about a current guitar practice amplifier? http://www.soundthoughts.co.uk/look/pignose.jpg The idea is to sound like a proper valve guitar amplifier, and it sort of does it. The Pignose is brilliant. I have one. http://www.kolumbus.fi/iain.churches/Pics/Pignose.jpg A huge sound from a tiny amp:-) Iain It isn't the same without the proper pig's nose volume knob. d |
#84
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
"flipper" wrote
My 'mini guitar amp' is a similar idea, except it's real tubes with more controls, headphone, and line out for recording. Interesting choice of valve. Apparently it was designed for use in cascode VHF amplifiers in TV sets. I guess the nearest European equivalent would be the ECC84. If anyone wants to try building one I've got a box-full of the PCC84 (same thing but with 7.0V heater). David. |
#85
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
"flipper" wrote My 'mini guitar amp' is a similar idea, except it's real tubes with more controls, headphone, and line out for recording. http://flipperhome.dyndns.org/Gemini%20x2.htm What I lovely little project - almost makes me wish I was still messing about with that good DIY valvey stuff!! @:-) |
#86
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
"flipper" wrote
I used a number of tricks. Current mirror under the power tubes for automatic bias, input FET buffer done as a HV 'tube' emulator, NPN follower tone stack buffer, and NPN phase splitter. But the tubes do the 'music' work. Are you using the two halves of one of your double triodes as a push-pull output pair? I have the service manual somewhere for an Ampex 451 tape recorder (circa 1965). That uses two double triodes in the line amp, the second (a 12AT7) configured as a push-pull pair. From the photo it looks as though your output transformer is a line-matching transformer for 70V/100V line, such a transformer wouldn't have been designed to cope with DC in the primary. But if you were able to drive it push-pull you'd get DC cancellation in the core. David. |
#87
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
"flipper" wrote in message ... On Mon, 21 Dec 2009 17:27:20 +0200, "Iain Churches" wrote: "Don Pearce" wrote in message ... On Sun, 20 Dec 2009 12:22:40 +0000 (GMT), Jim Lesurf wrote: I guess designers of commercial audio amps back then were more habituated to using transformers than nowdays. I didn't know about the above, but recall that some early domestic transistor amps included things like coupling transformers. How about a current guitar practice amplifier? http://www.soundthoughts.co.uk/look/pignose.jpg The idea is to sound like a proper valve guitar amplifier, and it sort of does it. The Pignose is brilliant. I have one. http://www.kolumbus.fi/iain.churches/Pics/Pignose.jpg A huge sound from a tiny amp:-) My 'mini guitar amp' is a similar idea, except it's real tubes with more controls, headphone, and line out for recording. http://flipperhome.dyndns.org/Gemini%20x2.htm Excellent:-) Pleased to see that there is someone still left on UKRA who actually builds something, and with valves too. Iain |
#88
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
"Don Pearce" wrote in message ... On Mon, 21 Dec 2009 17:27:20 +0200, "Iain Churches" wrote: "Don Pearce" wrote in message ... On Sun, 20 Dec 2009 12:22:40 +0000 (GMT), Jim Lesurf wrote: I guess designers of commercial audio amps back then were more habituated to using transformers than nowdays. I didn't know about the above, but recall that some early domestic transistor amps included things like coupling transformers. How about a current guitar practice amplifier? http://www.soundthoughts.co.uk/look/pignose.jpg The idea is to sound like a proper valve guitar amplifier, and it sort of does it. The Pignose is brilliant. I have one. http://www.kolumbus.fi/iain.churches/Pics/Pignose.jpg A huge sound from a tiny amp:-) Iain It isn't the same without the proper pig's nose volume knob. Rats!. Do you think mine is a worthless Chinese copy? Its output is tiny but its sound it *huge* - |
#89
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
On Wed, 23 Dec 2009 08:50:34 +0200, "Iain Churches"
wrote: "Don Pearce" wrote in message ... On Mon, 21 Dec 2009 17:27:20 +0200, "Iain Churches" wrote: "Don Pearce" wrote in message ... On Sun, 20 Dec 2009 12:22:40 +0000 (GMT), Jim Lesurf wrote: I guess designers of commercial audio amps back then were more habituated to using transformers than nowdays. I didn't know about the above, but recall that some early domestic transistor amps included things like coupling transformers. How about a current guitar practice amplifier? http://www.soundthoughts.co.uk/look/pignose.jpg The idea is to sound like a proper valve guitar amplifier, and it sort of does it. The Pignose is brilliant. I have one. http://www.kolumbus.fi/iain.churches/Pics/Pignose.jpg A huge sound from a tiny amp:-) Iain It isn't the same without the proper pig's nose volume knob. Rats!. Do you think mine is a worthless Chinese copy? Its output is tiny but its sound it *huge* - I'm sure it is real. Those must number among the last properly hand-made products in the world - no chance of mass production in Dafen. d |
#90
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
flipper wrote:
http://flipperhome.dyndns.org/Gemini%20x2.htm Excellent:-) Thank you. Pleased to see that there is someone still left on UKRA who actually builds something, and with valves too. Who knows. Maybe this year I'll get around to building the 807 amp I've already got the tubes for. Hey Flipper, Would love to see your amp but I've been getting 404s. Any suggestions ? TIA TonyL |
#91
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
flipper wrote:
On Wed, 30 Dec 2009 12:02:59 -0000, "TonyL" wrote: flipper wrote: http://flipperhome.dyndns.org/Gemini%20x2.htm Excellent:-) Thank you. Pleased to see that there is someone still left on UKRA who actually builds something, and with valves too. Who knows. Maybe this year I'll get around to building the 807 amp I've already got the tubes for. Hey Flipper, Would love to see your amp but I've been getting 404s. Any suggestions ? Yeah, I'll reboot the server. Sorry about that. It's running on a little webpal that's sitting on the edge and I've got a new puppy that loves to smack the thing into brain dead. He also likes to pull cables out of the router on that segment.. I just moved it to a more stable location so hopefully it'll stay up longer. Thanks Flipper, Gotit :-) Nice work ! Any chance of seeing a schematic ? |
#92
Posted to uk.rec.audio,rec.audio.tubes
|
|||
|
|||
The price of valves
On Wed, 30 Dec 2009 15:52:33 -0600, flipper wrote:
Well, there's some potentially proprietary stuff in there so I don't publish that one. I can talk about it, though. By publishing you establish your priority, so go ahead. d |
Reply |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Valves By the Ton | Vacuum Tubes | |||
FS: PX4 Valves and others | Vacuum Tubes | |||
What the hell are these valves ????????????????????? | Vacuum Tubes | |||
Ageing valves | General | |||
Valves, valves and more valves | Audio Opinions |