ok this is not working no replies about the schematic but that is ok i will manage without it
i will also post pictures of the mess i found inside that will be really funny since transitors inside the amp was diferent types, brands, models, with reversed pins at every stage
beyond that its a classic amp as we know it LTP + CCS ...no bootstrap ... with vbe and four transitors in the outpout stage per amplifier EFP configured
the machine is very low power ( not finished yet so i dont know ) but i will guess no more than 35+35 @8R
the problem i noticed is the vbe transitor was never mounted in the heatsink anyway ..
so i will relocate it anyway but anybody has a diferent opinion please let me know ...
regards sakis
i will also post pictures of the mess i found inside that will be really funny since transitors inside the amp was diferent types, brands, models, with reversed pins at every stage
beyond that its a classic amp as we know it LTP + CCS ...no bootstrap ... with vbe and four transitors in the outpout stage per amplifier EFP configured
the machine is very low power ( not finished yet so i dont know ) but i will guess no more than 35+35 @8R
the problem i noticed is the vbe transitor was never mounted in the heatsink anyway ..
so i will relocate it anyway but anybody has a diferent opinion please let me know ...
regards sakis
the schematic of the power amp unit from P25 and P35 is very close to that one of Mission Cyrus I and II, if I recall right.
Also Moth (UK) and Monrio (Italy) uses this topology by several of it's models arround 1995 until 1998 in their power amplifier stages (first stage: Darlington-LTP, second stage = predriver: differential amp and current mirror, third stage: PP class A/B power follower/ buffer, sometimes quasi complementary 30-50mA idle current)
Also Moth (UK) and Monrio (Italy) uses this topology by several of it's models arround 1995 until 1998 in their power amplifier stages (first stage: Darlington-LTP, second stage = predriver: differential amp and current mirror, third stage: PP class A/B power follower/ buffer, sometimes quasi complementary 30-50mA idle current)
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Where have you found Cambridge service manuals? I am in need of one for the Azur 340C
Magura
Cambridge P35
That is what Stan Curtis told me. He claims that is his design and it was between the P25 and P55. This was also quoted somewhere in the web that it is called "segmented passive equalization".
That is what Stan Curtis told me. He claims that is his design and it was between the P25 and P55. This was also quoted somewhere in the web that it is called "segmented passive equalization".
I have heard, that all new and vintage Cambrighe Audio Service Manuals are available.
Customer Care System
I will now try to order there this service manual from the integrated amplifier "P-35"
Customer Care System
I will now try to order there this service manual from the integrated amplifier "P-35"
i have repaired the amplifier without the schematic so there is no problem for me ... but still it would be nice to have ...
the only thing that troubles me beyond that the particular amp was canibalized wearing all shorts of transistors and parts inside .... still i had to replace a holly lot ( and some of them looked mama original ) to achieve a useable bandwidth ...
on start up after changing alsmot all semiconductors the bandwidth was bearly 12KHZ .... then found a few things wrong here and there guessed a few others that seemed reasonable and proceed from there ...
as we speak its working perfectly and with a happy bandwidth of almost 100 khz ... other than that its an ok amplifier but nothing too impressive ....
then again i never got the point of having 4 transistors per amplifier when you have a trafo that is bearly 100 w......
any way i am not going to spend time to hand draw a schematic ....
pictures coming any day
the only thing that troubles me beyond that the particular amp was canibalized wearing all shorts of transistors and parts inside .... still i had to replace a holly lot ( and some of them looked mama original ) to achieve a useable bandwidth ...
on start up after changing alsmot all semiconductors the bandwidth was bearly 12KHZ .... then found a few things wrong here and there guessed a few others that seemed reasonable and proceed from there ...
as we speak its working perfectly and with a happy bandwidth of almost 100 khz ... other than that its an ok amplifier but nothing too impressive ....
then again i never got the point of having 4 transistors per amplifier when you have a trafo that is bearly 100 w......
any way i am not going to spend time to hand draw a schematic ....
pictures coming any day
FYI the cambridge audio p35 is very similar to the ar amp. both were introduced back in 1984 in the uk. acoustic research was then under teledyne and the ar amp was manufactured by cambridge audio research. i believe the p35 was released short after the ar amp with minor modifications. i do have a working arm amp and did sent it for a repair once due to popping sound on the right channel (a common problem with the ar amp).
P35 details
I used to have a P35, they were fantastic. Unfortunately I left mine with a repair man who i think took a fancy to it. Told me it was beyond repair. I am pretty sure he still has it...
Anyway i can tell you they are fantastic bits of kit. I have the original spec sheets and operators manual if you are keen. It does not include the original circuit diagrams but does include test sheet for my amp showing 64 watts output power 1KHz 1%THD 8ohms both channels (75 watts single channel).
I can also tell you thet the original company was based at Home Farm Diddington Huntingdon (0480 811811 back then). I believe they sold the name on to Richer Sounds which is when mass production started and quality went. I never found another amp of similar sound quality until I moved into valves.....
I used to have a P35, they were fantastic. Unfortunately I left mine with a repair man who i think took a fancy to it. Told me it was beyond repair. I am pretty sure he still has it...
Anyway i can tell you they are fantastic bits of kit. I have the original spec sheets and operators manual if you are keen. It does not include the original circuit diagrams but does include test sheet for my amp showing 64 watts output power 1KHz 1%THD 8ohms both channels (75 watts single channel).
I can also tell you thet the original company was based at Home Farm Diddington Huntingdon (0480 811811 back then). I believe they sold the name on to Richer Sounds which is when mass production started and quality went. I never found another amp of similar sound quality until I moved into valves.....
Quite true... Cambridge Audio is now a brand of Audio Partnership plc who also manufacturer other brands such as Gale and Mordaunt-Short loudspeaker. Julian Richer, of Richer Sounds, owns a 51% stake in Audio Partnership... and Richer Sounds is th sole UK distributor of CA products.
Indeed, while the older products were good, and the new ones are not always bad designs, they suffer from poor build quality.
Indeed, while the older products were good, and the new ones are not always bad designs, they suffer from poor build quality.
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