Pye Mozart Stereo pre & power amp in a right old state! - UK Vintage Radio Repair and Restoration Discussion Forum

Rolf Startin · 13th Mar 2008, 6:37 pm

Hello everyone

Following the death of my father, I was clearing his loft and discovered a home-made wooden enclosure containing a PYE Mozart Stereo Pre and Power Amp combination! It's in a heck of a mess, no valves and a botched attempt at replacing the big can caps with axial electrolytics wrapped in insulating tape.

I am familiar with push pull valve amps, more specifically guitar amps, and I've restored a few, even successfully rewinding a fried output transformer, but i'm clueless

when it comes to this single-ended, Class A design. Nevertheless I am determined to restore this very special piece of history, not least in honour of my dad who was a notorious and very loveable bodger.

Now then, I saw Station X's report of his repairing Stuart's Mozart, and I downloaded JPEGs number 2 & 3 but could not access JPEG 1. Could this be the full preamp schematic? I'd love to see it if anyone has a copy.

Please can anyone tell me where I might buy a pair of (empty?) cap cans in order to fill them with modern radial electrolytics whilst preserving the appearance?

Thanks a lot!

Rolf Startin · 13th Mar 2008, 6:43 pm

.... and here's some photos! (should have thought of that earlier!)...

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Station X · 13th Mar 2008, 7:06 pm

Hello Rolf and welcome to the forums.

This would be well worth restoring.

PM me you email address and I'll send you the full manual for the Amp and pre-amp plus details of the different bias and pre-amp circuits.

Does your amp have cathode bias resistors for the output valves?

This would be well worth restoring.

Nickthedentist · 13th Mar 2008, 7:10 pm

Quote:

Originally Posted by Station X

This would be well worth restoring.

I totally agree. The condition is actually quite good

mickjjo · 13th Mar 2008, 7:18 pm

Some useful information and pictures of how nice they should look here

:-

http://homepage.ntlworld.com/hon.lau/PyeMozart.html

Regards, Mick.

Rolf Startin · 25th Mar 2008, 3:55 pm

Hiya Mick

It seems that everything NTL has begome Virgin-ated, and so the tantalising link you posted doesn't work!!!

I don't suppose you kept the htm page offline? I'd love to have a look.

Thanks

Rolf Startin · 28th Mar 2008, 2:22 pm

Graham

Thanks a million for the schematics - mine is not the cathode biassed species, the output tubes are biassed via 470K resistors to the control grids per your sketch.

Am I at a disadvantage here, i.e. is there a perceptible difference in the sound or some other compromise going on? I wonder why Pye changed the arrangement.... non-catastrophic failure mode perhaps?

Thanks Again

Station X · 28th Mar 2008, 6:48 pm

I'm sorry Rolf, but I can't answer that one. I don't even know which version came first, the cathode biased version or the version where the bias is derived from a separate bias supply.

I do know that even a non audiophile like myself loved the sound of the amp, even when connected to speakers rescued from a skip. I soak tested it for several days and it was a wrench handing it back to its owner.

magnastat · 28th Mar 2008, 7:38 pm

http://web.archive.org/web/200708080...PyeMozart.html

I agree.
Pye amps are very special. In a moment of madness I bought a pair of PF91s.
Stunning, absolutely stunning.

yestertech · 29th Mar 2008, 1:37 am

Quote:

Originally Posted by magnastat

http://web.archive.org/web/200708080...PyeMozart.html

I bought a pair of PF91s.
Stunning, absolutely stunning.

Any chance of a pic ? Andy

Tractorfan · 1st Apr 2008, 6:35 pm

I had the mono version out of a school's record player & regretted selling it. Should have looked for another one instead. Filly fod!
Cheers, Pete.

Dalek55 · 15th May 2008, 1:23 pm

I too have a Pye Mozart Stereo Preamp which I wish to restore.
Unfortunately I have lost the schematic over the 15 odd years its been in storage.
I would really appreciate it if someone could send me a copy.

Thanks,

Ian

Station X · 16th May 2008, 4:32 pm

PM or email me your email adress and it shall be yours.

Dalek55 · 20th May 2008, 1:48 pm

Graham,
Just received the Pye Mozart Manual, many thanks.
Award yourself a medal.

Cheers,

Ian

Rolf Startin · 20th May 2008, 5:25 pm

Hi Ian

Best of British and all that! Have you taken any pictures?

Cheers

Dalek55 · 23rd May 2008, 9:00 am

Hi Rolf,
No pictures taken, but its in a similar state to your own.
I have built a 'modern' power supply for it, and added a pair of phono sockets for the output onto the case. After a few voltage measurements and no smoke I connected it to one of my solid state power amps, plugged in the MP3 player and music came out. Sounds good too. Now that it is fundamentally OK, I shall work on the cosmetics and maybe change a few capacitors and probably new valves.

onward!

jim221 · 1st Jul 2008, 6:02 pm

Hi There Graham,
I too have just obtained a stereo mozart. Unfortunately it doesn't have a control unit with it. (Anyone know where there is a control unit) it is in a much better state than Rolfs and I wondered if I could lean on you for a copy of the manual. I have not had a chance to power it up yet as I need another EL34. I think a mullard EL 34 is going to cost me more than I paid for the Amp.
Best Regards
Jim

mastermanx2001 · 1st Jul 2008, 9:44 pm

Perhaps try the JJ KT7 in place of the Mullard EL34, its a good valve and cheap.

Station X · 1st Jul 2008, 9:54 pm

Jim.

You'll have to send me your email address in a PM, so I can email you the manual. I can't send attachments via the forum.

jim221 · 3rd Jul 2008, 11:01 am

Hi Graham, thank you for the pm and attachment. The information will certainly come in handy.
Thanks again
Jim

13th Mar 2008, 6:37 pm	#1
Rolf Startin Retired Dormant Member Join Date: Mar 2008 Location: Bournemouth Posts: 8	Pye Mozart Stereo pre & power amp in a right old state! Hello everyone Following the death of my father, I was clearing his loft and discovered a home-made wooden enclosure containing a PYE Mozart Stereo Pre and Power Amp combination! It's in a heck of a mess, no valves and a botched attempt at replacing the big can caps with axial electrolytics wrapped in insulating tape. I am familiar with push pull valve amps, more specifically guitar amps, and I've restored a few, even successfully rewinding a fried output transformer, but i'm clueless when it comes to this single-ended, Class A design. Nevertheless I am determined to restore this very special piece of history, not least in honour of my dad who was a notorious and very loveable bodger. Now then, I saw Station X's report of his repairing Stuart's Mozart, and I downloaded JPEGs number 2 & 3 but could not access JPEG 1. Could this be the full preamp schematic? I'd love to see it if anyone has a copy. Please can anyone tell me where I might buy a pair of (empty?) cap cans in order to fill them with modern radial electrolytics whilst preserving the appearance? Thanks a lot!

13th Mar 2008, 6:43 pm	#2
Rolf Startin Retired Dormant Member Join Date: Mar 2008 Location: Bournemouth Posts: 8	Pye Mozart Stereo pre & power amp in a right old state! .... and here's some photos! (should have thought of that earlier!)...

13th Mar 2008, 7:06 pm	#3
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: Pye Mozart Stereo pre & power amp in a right old state! Hello Rolf and welcome to the forums. This would be well worth restoring. PM me you email address and I'll send you the full manual for the Amp and pre-amp plus details of the different bias and pre-amp circuits. Does your amp have cathode bias resistors for the output valves? This would be well worth restoring. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

13th Mar 2008, 7:18 pm	#5
mickjjo Rest in Peace Join Date: Jul 2004 Location: Dartford, Kent, UK. Posts: 1,661	Re: Pye Mozart Stereo pre & power amp in a right old state! Some useful information and pictures of how nice they should look here :- http://homepage.ntlworld.com/hon.lau/PyeMozart.html Regards, Mick.

25th Mar 2008, 3:55 pm	#6
Rolf Startin Retired Dormant Member Join Date: Mar 2008 Location: Bournemouth Posts: 8	Re: Pye Mozart Stereo pre & power amp in a right old state! Hiya Mick It seems that everything NTL has begome Virgin-ated, and so the tantalising link you posted doesn't work!!! I don't suppose you kept the htm page offline? I'd love to have a look. Thanks

28th Mar 2008, 2:22 pm	#7
Rolf Startin Retired Dormant Member Join Date: Mar 2008 Location: Bournemouth Posts: 8	Re: Pye Mozart Stereo pre & power amp in a right old state! Graham Thanks a million for the schematics - mine is not the cathode biassed species, the output tubes are biassed via 470K resistors to the control grids per your sketch. Am I at a disadvantage here, i.e. is there a perceptible difference in the sound or some other compromise going on? I wonder why Pye changed the arrangement.... non-catastrophic failure mode perhaps? Thanks Again

28th Mar 2008, 6:48 pm	#8
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: Pye Mozart Stereo pre & power amp in a right old state! I'm sorry Rolf, but I can't answer that one. I don't even know which version came first, the cathode biased version or the version where the bias is derived from a separate bias supply. I do know that even a non audiophile like myself loved the sound of the amp, even when connected to speakers rescued from a skip. I soak tested it for several days and it was a wrench handing it back to its owner. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

28th Mar 2008, 7:38 pm	#9
magnastat Retired Dormant Member Join Date: May 2007 Location: East Sussex, UK. Posts: 40	Re: Pye Mozart Stereo pre & power amp in a right old state! http://web.archive.org/web/200708080...PyeMozart.html I agree. Pye amps are very special. In a moment of madness I bought a pair of PF91s. Stunning, absolutely stunning.

1st Apr 2008, 6:35 pm	#11
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,184	Re: Pye Mozart Stereo pre & power amp in a right old state! I had the mono version out of a school's record player & regretted selling it. Should have looked for another one instead. Filly fod! Cheers, Pete. __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

15th May 2008, 1:23 pm	#12
Dalek55 Retired Dormant Member Join Date: May 2008 Location: Winchester UK Posts: 3	Re: Pye Mozart Stereo pre & power amp in a right old state! I too have a Pye Mozart Stereo Preamp which I wish to restore. Unfortunately I have lost the schematic over the 15 odd years its been in storage. I would really appreciate it if someone could send me a copy. Thanks, Ian

16th May 2008, 4:32 pm	#13
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: Pye Mozart Stereo pre & power amp in a right old state! PM or email me your email adress and it shall be yours. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

20th May 2008, 1:48 pm	#14
Dalek55 Retired Dormant Member Join Date: May 2008 Location: Winchester UK Posts: 3	Re: Pye Mozart Stereo pre & power amp in a right old state! Graham, Just received the Pye Mozart Manual, many thanks. Award yourself a medal. Cheers, Ian

20th May 2008, 5:25 pm	#15
Rolf Startin Retired Dormant Member Join Date: Mar 2008 Location: Bournemouth Posts: 8	Re: Pye Mozart Stereo pre & power amp in a right old state! Hi Ian Best of British and all that! Have you taken any pictures? Cheers

23rd May 2008, 9:00 am	#16
Dalek55 Retired Dormant Member Join Date: May 2008 Location: Winchester UK Posts: 3	Re: Pye Mozart Stereo pre & power amp in a right old state! Hi Rolf, No pictures taken, but its in a similar state to your own. I have built a 'modern' power supply for it, and added a pair of phono sockets for the output onto the case. After a few voltage measurements and no smoke I connected it to one of my solid state power amps, plugged in the MP3 player and music came out. Sounds good too. Now that it is fundamentally OK, I shall work on the cosmetics and maybe change a few capacitors and probably new valves. onward!

1st Jul 2008, 6:02 pm	#17
jim221 Pentode Join Date: Dec 2005 Location: Dereham, Norfolk, UK. Posts: 140	Re: Pye Mozart Stereo pre & power amp in a right old state! Hi There Graham, I too have just obtained a stereo mozart. Unfortunately it doesn't have a control unit with it. (Anyone know where there is a control unit) it is in a much better state than Rolfs and I wondered if I could lean on you for a copy of the manual. I have not had a chance to power it up yet as I need another EL34. I think a mullard EL 34 is going to cost me more than I paid for the Amp. Best Regards Jim

1st Jul 2008, 9:44 pm	#18
mastermanx2001 Retired Dormant Member Join Date: Jun 2007 Location: London, UK. Posts: 366	Re: Pye Mozart Stereo pre & power amp in a right old state! Perhaps try the JJ KT7 in place of the Mullard EL34, its a good valve and cheap.

1st Jul 2008, 9:54 pm	#19
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: Pye Mozart Stereo pre & power amp in a right old state! Jim. You'll have to send me your email address in a PM, so I can email you the manual. I can't send attachments via the forum. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

3rd Jul 2008, 11:01 am	#20
jim221 Pentode Join Date: Dec 2005 Location: Dereham, Norfolk, UK. Posts: 140	Re: Pye Mozart Stereo pre & power amp in a right old state! Hi Graham, thank you for the pm and attachment. The information will certainly come in handy. Thanks again Jim