Cool!
So the only non standard things are the main supply caps, signal coupling and feedback, and opamps?
Glad you got there in the end
Yep, bang on! and the IEC.
I've been looking back at you PM regarding the amp. This one......
*Begin with replacing the main PSU caps with the Mundorfs.
*Upgrade the regulators, and rectifier diodes.
*Then try some different caps in the signal path (film are best).
*After that have a play with the poweramp feedback cap.
*Then finally try some different opamps.
The mundorfs are done, however they're 50v with only 3v headroom so I'm looking for the 80v versions at the mo.
Signal and feedback caps are done (silmics)
Opamps are done (LM4562's on sockets)
Just leaves the regs and diodes. The main (x2) 4 pin rectifiers are KBU 8D by HY and the pre amp rectifiers are DB104 again by HY.
Any ideas on what to replace them with??
I'll jot the reg numbers down soon, will be looking for better std regs rather than discrete modules like the classD's.
Danke!
3v is a bit close but should be fine. You could always go with 63v caps too. If you do go for higher rated caps why not go for a little more capacitance too? This should help with bass and dyanmics.
Heres a simple regulator mod that is cheap and works wonders: linky. Its shown applied to a LM317 but can easily be implemented on a LM78** or 79** type reg. PM me if you need a hand.
Good quality Shottkey diodes for preamp and Hexfreds for the poweramp. I cant advise on the exact part numbers but Brent should be able to help.
EDIT: Worth trying these for signal coupling: WIMA MKS2 3.3uF/50v Film caps will be far superior to any 'however expensive' electrolytic cap where the audio signal is passing through. Get a few extra, you'll need the for the regulator mod.
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Try the LME49725, LME49723.
No thanks, I'm looking for rectifiers and regs, not opamps.
3v is a bit close but should be fine. You could always go with 63v caps too. If you do go for higher rated caps why not go for a little more capacitance too? This should help with bass and dyanmics.
Heres a simple regulator mod that is cheap and works wonders: linky. Its shown applied to a LM317 but can easily be implemented on a LM78** or 79** type reg. PM me if you need a hand.
Good quality Shottkey diodes for preamp and Hexfreds for the poweramp. I cant advise on the exact part numbers but Brent should be able to help.
EDIT: Worth trying these for signal coupling: WIMA MKS2 3.3uF/50v Film caps will be far superior to any 'however expensive' electrolytic cap where the audio signal is passing through. Get a few extra, you'll need the for the regulator mod.
Cheers mike!
Would 15000uf 63v be ok instead of the 10000uf 50v?
Looked at the reg 'linky', looks very good but what are the components??
I'll ask Brent for a 'lil' help regarding the rectifiers soon.
Thanks.....
"BC547c, 3.3uF film, 10K, and 10/22uF tant". I'll send you a simple schematic shortly.
Those caps will be fine so long as they fit in the chassis. Were you thinkig of sticking with Mundorfs or is there something else in mind?
With Diodes I think Shottkey DQ09 is the one, but I could be wrong about the lil number three. On the Hexfreds you'll probably be fine with the ones he (Brent) stocks @ his website. ( I bet those are he ones he'll recommend
)
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For the positive version:
I haven't got a drawing for the negative. You would use a negative reg and substitute the BC547 for a BC557. The collector needs to go to the voltage input, and the emitter feeds the reg. Just use the reg you need according to the desired voltage (re-use the existing regs). This circuit will add about <1v dropout so check your raw supply has enough headroom. It should be fine though.
I haven't got a drawing for the negative. You would use a negative reg and substitute the BC547 for a BC557. The collector needs to go to the voltage input, and the emitter feeds the reg. Just use the reg you need according to the desired voltage (re-use the existing regs). This circuit will add about <1v dropout so check your raw supply has enough headroom. It should be fine though.
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With Diodes I think Shottkey DQ09 is the one, but I could be wrong about the lil number three. On the Hexfreds you'll probably be fine with the ones he (Brent) stocks @ his website. ( I bet those are he ones he'll recommend
Remember the original diodes are in a bridge package, not discrete diodes.
For the positive version:
I haven't got a drawing for the negative. You would use a negative reg and substitute the BC547 for a BC557. The collector needs to go to the voltage input, and the emitter feeds the reg. Just use the reg you need according to the desired voltage (re-use the existing regs). This circuit will add about <1v dropout so check your raw supply has enough headroom. It should be fine though.
Thanks again Mike, Great help!
Can I use discrete diodes? the originals are in bridge package.
Ta.
It's possible, if a bit messy:
http://www.hificollective.co.uk/pdf/diode.pdf
Alternatively you could build the diodes onto a piece of veroboard. How comfortable are you building such circuits? How far do you want to take the Nad?
http://www.hificollective.co.uk/pdf/diode.pdf
Alternatively you could build the diodes onto a piece of veroboard. How comfortable are you building such circuits? How far do you want to take the Nad?
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I'd be happy to build the circuit.
I'm unsure as yet, do you have any ideas what I could do?
I will put NAD C515BEE player service manual in public domain. I think there is no problem in doing this, and I own this player.
I found this link
http://nadelectronics.com/content/100504165228-C515BEESM.pdf
for downloading the manual. All service manuals are in /content/ directory
If there was anyway to download the entire directory, all service manual would be avaible...
I found this link
http://nadelectronics.com/content/100504165228-C515BEESM.pdf
for downloading the manual. All service manuals are in /content/ directory
If there was anyway to download the entire directory, all service manual would be avaible...
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