Hello all - I hope your projects are going well.
Today I got a CA Azur 840a for a very reasonable price. The seller claimed input one was dead on both the RCA's and XLR's. Reading up on this amp - I discovered the inputs are controlled by relays - and my suspicion was that the input one relay had gotten sticky. Not so - I can hear it activate robustly. Turns out the wee toggle switch on the rear panel that selects either the RCA or XLR inputs has been broken and is flopping about.
I found the service manual and I cannot, for the life of me, find mention of this switch anywhere in it.
In my initial listening - I like the sound of this amp - and I'd like to get it working completely. All the other inputs operate fine.
I'm happy to either replace the switch - but would love to discover the part # so I can order it before taking the amp apart - or simply rewire the circuit so that input one is hardwired to the XLR inputs. I don't often sell gear and this will likely stay in my collection for a good while. So getting it back to factory spec isn't important to me.
But I can't discover in the schematics or the BOM what's needed for either approach.
Any tips?
Link to the service manual is here: https://elektrotanya.com/cambridge-audio_azur-840a_ver.2_sm.pdf/download.html
Thanks in advance!
RK
Today I got a CA Azur 840a for a very reasonable price. The seller claimed input one was dead on both the RCA's and XLR's. Reading up on this amp - I discovered the inputs are controlled by relays - and my suspicion was that the input one relay had gotten sticky. Not so - I can hear it activate robustly. Turns out the wee toggle switch on the rear panel that selects either the RCA or XLR inputs has been broken and is flopping about.
I found the service manual and I cannot, for the life of me, find mention of this switch anywhere in it.
In my initial listening - I like the sound of this amp - and I'd like to get it working completely. All the other inputs operate fine.
I'm happy to either replace the switch - but would love to discover the part # so I can order it before taking the amp apart - or simply rewire the circuit so that input one is hardwired to the XLR inputs. I don't often sell gear and this will likely stay in my collection for a good while. So getting it back to factory spec isn't important to me.
But I can't discover in the schematics or the BOM what's needed for either approach.
Any tips?
Link to the service manual is here: https://elektrotanya.com/cambridge-audio_azur-840a_ver.2_sm.pdf/download.html
Thanks in advance!
RK
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Sure - but two thoughts about that.
1. I'd love some guidance to learn what I'm doing wrong in interpreting the schematics. So I came to a hive of wisdom with that hope.
2. The part is likely about $2 from Digi-Key and likely $20 plus shipping from CA. Or more. I learned this the hard way when I had to replace a switch on my LS-15. Although it uses high quality C&K switches, Audio Research was charging $50USD per switch. I'd like to avoid that path if possible.
Sure - happy to take one - but of what? The switch? I haven't opened the amp yet - so I don't have any internal views. I'm mechanically capable - so getting to and replacing the switch isn't my challenge. It's understanding the schematics (So that I might modify the circuit) and finding the part # in the service manual that I'd like help with. Making sense?
In general, you are more likely to get a quick and positive response if you post everything here rather than ask people to navigate away .
If you post the schematic then it's easy enough for any passerby to have a quick look. If in addition to that, you post a pic of the switch with what it's connected to then that helps too.
If you post the schematic then it's easy enough for any passerby to have a quick look. If in addition to that, you post a pic of the switch with what it's connected to then that helps too.
Here is the service manual. The switch does not seem to be on the schematic, so someone could have added it.
Just bypass the switch and use only the input of your choice.
Just bypass the switch and use only the input of your choice.
Thanks so much for confirming my suspicion that it's not there! I am indeed not totally incompetent. : )
I'll open it up and give that a try. Thanks again.
RK
I'll open it up and give that a try. Thanks again.
RK
Sure there do - there are 4 C&K momentary switches on the front of the unit that control several functions (I just replaced one last month on my LS-15) C&K 7108P1YCBES is the part #.
But I agree they don't have a switch on the rear to select RCA or XLR like the CA amp I have. I'll suggest we're both right. : )
RK
But I agree they don't have a switch on the rear to select RCA or XLR like the CA amp I have. I'll suggest we're both right. : )
RK
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Those are good points and I could have done a better job on that. But the schematics were numerous and I didn't even know which one to post - because I couldn't find the switch anywhere (it turns out because it NOT THERE!). I did post a link to the service manual.
I was also hoping that someone knew the part # so I could order it BEFORE I opened up the unit to limit its downtime - but that appears not to be possible - so I will indeed open it up.
Agree with you - I popped the cover off and here's the inside - not yet useful for our switch fixing purposes - but a nice 840a nudie. ; )
It appears you have two power transformers. Of the two the smaller one is more likely for the line stages where signal switching and perhaps output relay delays and dc output protection are to be powered. The latter relays should be large in size.
I am could not see where the toggle switch would be in your picture. You should check the wiring of the toggle switch to see where the wires lead. If this is not in the manual with a manufacturers name and part number. I think it was an add-on by the previous owner for some personal switching preference. If so you could arrange your wiring to reflect the circuit connections in the makers service manual
I am could not see where the toggle switch would be in your picture. You should check the wiring of the toggle switch to see where the wires lead. If this is not in the manual with a manufacturers name and part number. I think it was an add-on by the previous owner for some personal switching preference. If so you could arrange your wiring to reflect the circuit connections in the makers service manual
The switch is a standard feature from the factory. I'm in conversations with CA on the matter and I'll see what they say about this. I'll post more detailed pics when I take it apart.
FWIW, the CA tech support folks have replied very quickly - we'll see if they're helpful or not.
RK
FWIW, the CA tech support folks have replied very quickly - we'll see if they're helpful or not.
RK
That seems to be a good sign of customer service here is hoping that results in customer satisfaction
Well, speedy doesn't mean helpful. : (
Here's CA's official response...
"We have been instructed not to supply component-level spare parts to unauthorized parties.
All stock of available parts is intended solely for use by our authorized repair and service centers worldwide and is reserved for them."
So - with an inadequate service manual (As confirmed above, the manual DOES NOT detail this switch, its wiring or the circuit it's in) and no parts available to the end user - this isn't a fix one can easily do on their own. While I do appreciated their position of protecting their repair network, and perhaps reducing liability exposure - in an age when independent repair shops are incredibly rare - and the hobby itself isn't exactly thriving - this policy seems particularly short-sighted and injurious to the market.
So be warned - if you are thinking of buying used Cambridge Audio gear (and as we know that often funds the purchase of NEW CA gear upstream) think carefully about doing so. I'll not do it again and have told CA that. They've lost me as a customer for life. Shame.
RK
Here's CA's official response...
"We have been instructed not to supply component-level spare parts to unauthorized parties.
All stock of available parts is intended solely for use by our authorized repair and service centers worldwide and is reserved for them."
So - with an inadequate service manual (As confirmed above, the manual DOES NOT detail this switch, its wiring or the circuit it's in) and no parts available to the end user - this isn't a fix one can easily do on their own. While I do appreciated their position of protecting their repair network, and perhaps reducing liability exposure - in an age when independent repair shops are incredibly rare - and the hobby itself isn't exactly thriving - this policy seems particularly short-sighted and injurious to the market.
So be warned - if you are thinking of buying used Cambridge Audio gear (and as we know that often funds the purchase of NEW CA gear upstream) think carefully about doing so. I'll not do it again and have told CA that. They've lost me as a customer for life. Shame.
RK
So here's news - CA - has further replied - after I told them I was disappointed about their lack of support. They now say that may indeed "may" be able to offer some help, with the caveats that the unit is over 15 years old and shipping of any parts they might have could be crazy expensive - which is fair and appropriate.
I've made a detailed request - and we'll see what they come back with. But I don't think I should have to express my profound disappointment in their level of service (or lack thereof) to get better service. So, I'll proceed with caution at this point and see how it goes.
I've made a detailed request - and we'll see what they come back with. But I don't think I should have to express my profound disappointment in their level of service (or lack thereof) to get better service. So, I'll proceed with caution at this point and see how it goes.