The recent Azur range looks like a completely different kettle of fish compared to the older A, C, D ranges. Theres a lot more stuff crammed into the cases.
One of the things I like about the older CA stuff is the thoughtful layout inside. I used to have a D500SE which had a transformer at the back. The transport and associated electronics at one side and the Dac and Analogue section at the other side of the case with loads of room in between. It also had synchronous reclocking.
The only thing I didn't like about the amps was that the input sockets at the back were often connected to the preamp at the front by long parallel runs of thin PCB track which just seems a terrible thing to do.
Can anyone say if this was a design thing or did it only happen once the accountant started complaining about production costs.
One of the things I like about the older CA stuff is the thoughtful layout inside. I used to have a D500SE which had a transformer at the back. The transport and associated electronics at one side and the Dac and Analogue section at the other side of the case with loads of room in between. It also had synchronous reclocking.
The only thing I didn't like about the amps was that the input sockets at the back were often connected to the preamp at the front by long parallel runs of thin PCB track which just seems a terrible thing to do.
Can anyone say if this was a design thing or did it only happen once the accountant started complaining about production costs.
a300 service manual
Hi baskiria , primalsea
Can you send me the service manual for the A300 ?
I have one that have a buzzing issue.
Same as described in this thread (buzz when the amp is on at any volume with or without source connected to the amp but stop when the power is removed and the amp is running from the cap).
Thanks a lot,
Stephan
Hi baskiria , primalsea
Can you send me the service manual for the A300 ?
I have one that have a buzzing issue.
Same as described in this thread (buzz when the amp is on at any volume with or without source connected to the amp but stop when the power is removed and the amp is running from the cap).
Thanks a lot,
Stephan
I was going to say, that a300 looks suspciously like a doug self circuit, in his books, its very close indeed, I think too much so to be a coincidence....
also, I think they have made a big error with the pricing of the big 840,l everyone knows cambridge are richer sounds, and none in their right mind would pay £800 for a richer sounds amp, I think they would still struggle to get £450 for it, £350 more like....I don't reckon they will sell many at all at that price, esp. as they are made in china for very little indeed, the posh xd bias doesn't look at all expensive at all, and would add very little to an already standard amplifier.
also, I think they have made a big error with the pricing of the big 840,l everyone knows cambridge are richer sounds, and none in their right mind would pay £800 for a richer sounds amp, I think they would still struggle to get £450 for it, £350 more like....I don't reckon they will sell many at all at that price, esp. as they are made in china for very little indeed, the posh xd bias doesn't look at all expensive at all, and would add very little to an already standard amplifier.
Hi,
I've been traveling for a while so not much progress with the amp.
I've sent it for a quick check but people there said the amp has no problem. This is a bit frustrating since some of the people from there said they can hear the buzz some not. But at the end they said the amp is fine and this is probably a grounding issue at home.
I did try a few things: another amp (no issue with it
) but anything else fails (no ground, different plug, switch off everything at home except the amp and the source, filter, etc ...).
I've opened a ticket with Cambridge Audio as well but this was useless. They guy is taking forever to reply and so far he only suggested the things I've already tried.
The good news is I've found a shop that is willing to take the amp if i buy another one. I'll probably go this way since I'm not good enough to troubleshoot it ...
Thanks,
--stephan
I've been traveling for a while so not much progress with the amp.
I've sent it for a quick check but people there said the amp has no problem. This is a bit frustrating since some of the people from there said they can hear the buzz some not. But at the end they said the amp is fine and this is probably a grounding issue at home.
I did try a few things: another amp (no issue with it
) but anything else fails (no ground, different plug, switch off everything at home except the amp and the source, filter, etc ...).I've opened a ticket with Cambridge Audio as well but this was useless. They guy is taking forever to reply and so far he only suggested the things I've already tried.
The good news is I've found a shop that is willing to take the amp if i buy another one. I'll probably go this way since I'm not good enough to troubleshoot it ...
Thanks,
--stephan
Sorry, but I could not find the schematics. I'll try to find them again, I just run out of time.
I also have a light 50hz-like hum when I turn the pot all the way up. I assume it is because of the power supply. It uses a really simple topology, and far not the best one. Isn't it possible, that the hum you hear is "factory condition"?
I also have a light 50hz-like hum when I turn the pot all the way up. I assume it is because of the power supply. It uses a really simple topology, and far not the best one. Isn't it possible, that the hum you hear is "factory condition"?
By the way, it's the hum that really bugs me, it's the buzzing noise.
It does not go up when increasing the volume (it's stable all the time).
It only stops when the amp is switched off (but the amp is still running for a short time - discharge).
The noise is not very high but you can hear it when there is no music playing.
--stephan
It does not go up when increasing the volume (it's stable all the time).
It only stops when the amp is switched off (but the amp is still running for a short time - discharge).
The noise is not very high but you can hear it when there is no music playing.
--stephan
It seems that it's not the preamp then, nor the signal line. Something must be wrong around your power supply. I would check the grounding around the supply first... Maybe trying the amp with an other toroid could also lead you closer to the solution.
Just an other idea: are the rectifier diodes all ok?
Edit: and another: isn't it possible, that the amp picks up some kind of "garbage signal" from the electrical system? I heard it somewhere, that these high-to-low voltage converters (transformator houses that are on the street), can make some strange things... This amp picks it, and others you tried don't (as I read that you tried others to exclude this problem)...
I hope you could understand what I'm trying to explain with my "not so well" english...
Just an other idea: are the rectifier diodes all ok?
Edit: and another: isn't it possible, that the amp picks up some kind of "garbage signal" from the electrical system? I heard it somewhere, that these high-to-low voltage converters (transformator houses that are on the street), can make some strange things... This amp picks it, and others you tried don't (as I read that you tried others to exclude this problem)...
I hope you could understand what I'm trying to explain with my "not so well" english...
At this point I should apologise for not piping in earlier.
Don't worry baskiria, I sent the schematics to rastafazz several months ago...
I believe I have exactly the same problem as rastafazz, but unfortunately haven't had access to my amp for several months (due to getting an electronics technician job (unfortunately not as glamorous as it sounds!) and moving away from my parent's house). If I get a chance over my week-long Christmas break, I'll look into the problem again.
I think I've mentioned it before somewhere, but my ex-housemate used to have an A300 V2 as well. When I last saw him, I asked if I could hear his amp - it seemed to be exhibiting the same symptons (though not quite as badly as mine - bearing in mind that his speakers are different).
The noise I hear is definitely more of a rough buzz than your standard 50Hz hum (but sounds like around 50Hz).
Good luck,
Rob
Don't worry baskiria, I sent the schematics to rastafazz several months ago...
I believe I have exactly the same problem as rastafazz, but unfortunately haven't had access to my amp for several months (due to getting an electronics technician job (unfortunately not as glamorous as it sounds!) and moving away from my parent's house). If I get a chance over my week-long Christmas break, I'll look into the problem again.
I think I've mentioned it before somewhere, but my ex-housemate used to have an A300 V2 as well. When I last saw him, I asked if I could hear his amp - it seemed to be exhibiting the same symptons (though not quite as badly as mine - bearing in mind that his speakers are different).
The noise I hear is definitely more of a rough buzz than your standard 50Hz hum (but sounds like around 50Hz).
Good luck,
Rob
thank you for your help. We have now looked at the amp and found that it might be the output transistors that are labelled U201 SAP15. N and U202 SAP15P - interestingly inside the amp they are labelled SAP10N SAP10P - would this have any effect on operation of the amp. So i'm going to track down a couple and solder them in. If anybody has a good place to get them in the UK please let me know. RS catalogue doesn't as far as i can tell.
thanks a lot
thanks a lot
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