NAD C515BEE is finished.............
Hello,
From start to finish in 6ish weeks, 67 replacement caps, 3 Class D regs, opamps, CMC silver rca's, alot of dampening, a re-wire, a clock kit, a 12v toroidal, reels of mundorf solder, ground work, removal of un-needed bits, burnt fingers, quite a few problems, some mistakes, alot of shouting, waiting for parts to arrive on the slow boat from China and it's finished!
I've had a hard time finding any info on the 515, there's nothing out there at all. Nad themselves are useless. Trying to decipher chinese and Japanese is far too hard. So I had to rely on guess work and questions placed upon diyaudio.
What's the outcome? It's been a headache but it was well worth it and the Brucey bonus is......it sounds great!
I'd like to thank amc148 and Bill_P for their time, help and great info and Nick at amplifier valve kits, HIFI pre-amplifiers, speaker kits, upgrade components for a speedy, helpfull and excellent service.
There's a photo attached if anyone's interested.
Chow fa now
Hello,
From start to finish in 6ish weeks, 67 replacement caps, 3 Class D regs, opamps, CMC silver rca's, alot of dampening, a re-wire, a clock kit, a 12v toroidal, reels of mundorf solder, ground work, removal of un-needed bits, burnt fingers, quite a few problems, some mistakes, alot of shouting, waiting for parts to arrive on the slow boat from China and it's finished!
I've had a hard time finding any info on the 515, there's nothing out there at all. Nad themselves are useless. Trying to decipher chinese and Japanese is far too hard. So I had to rely on guess work and questions placed upon diyaudio.
What's the outcome? It's been a headache but it was well worth it and the Brucey bonus is......it sounds great!
I'd like to thank amc148 and Bill_P for their time, help and great info and Nick at amplifier valve kits, HIFI pre-amplifiers, speaker kits, upgrade components for a speedy, helpfull and excellent service.
There's a photo attached if anyone's interested.
Chow fa now
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Forgot to mention the other half of the system is almost finished too. It's been within the same 6ish weeks as the CDP and the same story regarding Mundorf caps, Welwyn resistors, opamps, re-wire, etc etc.
Just the CMC binding posts and RCA's to drop in and it's done.......
I'm extremely impatient and need everything done 'now' but some things have to wait.
All in all, it's coming on nicely and it sounds super, even if it is only for the office.
Just the CMC binding posts and RCA's to drop in and it's done.......
I'm extremely impatient and need everything done 'now' but some things have to wait.
All in all, it's coming on nicely and it sounds super, even if it is only for the office.
Hello Andrea,
I started with the LM4562MA opamps then changed to LME49720HA (tin hats) that are TO99 fitment but I soldered them direct to the smt. There was no room under the board so I had to drill the chassis and finish them with grommets. If I do say so myself, It looks like it came from the factory so that ended up being good news.
The D/A chip is the 24/192 Sigma/Delta.
You're not done yet! You still have to replace the output circuitry with a discrete output stage!
Well Bill Fuss, you may be onto something there. Only a few hours after saying it's finished, I've been contemplating adding 3 more toroidals for the dac and opamps, changing more diodes, resistors etc etc. When will it be complete?? my answer would probably be 'never', but who knows?
I might start on my Meridian next??
But then I might not and go back to the 515bee and go for a discrete output, any recommendations??
I'm glad to see that you got the player going.
What model of DAC is this player using? You said before that it is a 24 bit / 192 kHz delta sigma, but that describes the function. We were looking for something like "it's a PCM1702" or similar.
Depending on the model of DAC, I don't know how much more I would do to it if I were you. It just doesn't seem to be, on the surface, a player worth spending a whole lot of time and money on. That super intergrated VLSI, the one that does clock generation among a million other things, is the sort of thing I would expect to find in a 'boom box'.
That's not to say that this is nesessarily a bad thing, there is a huge thread on a boom box player, but its just not the platform I would have chosen to modify.
What model of DAC is this player using? You said before that it is a 24 bit / 192 kHz delta sigma, but that describes the function. We were looking for something like "it's a PCM1702" or similar.
Depending on the model of DAC, I don't know how much more I would do to it if I were you. It just doesn't seem to be, on the surface, a player worth spending a whole lot of time and money on. That super intergrated VLSI, the one that does clock generation among a million other things, is the sort of thing I would expect to find in a 'boom box'.
That's not to say that this is nesessarily a bad thing, there is a huge thread on a boom box player, but its just not the platform I would have chosen to modify.
Thanks for your input (as disheartening as it was) but I'm not really into following the 'norm', hence no CD63.
The nad cd/amp combo & B&W's were bought 'just' for office at home and considering 95% of my working life is at our main premesis, they're rarely used so I thought I'd have a little play with them but then I got a bit carried away. I own other systems which are far, far better but that's another story.
That really depends on the dac chip, whether it is voltage or current output. IMHO, the implementation of the chip is as important as the particular chip used.
I'm a recent, fervent convert and promoter of using line OP trafos with voltage out dac chips, the simplest and most direct way of extracting everything the chip has.
For I/V conversion, jfets are hard to beat. Spencer had some inexpensive kits a while back that he has recently redesigned that are relatively easy to implement. Borbely also has a kit but they are much more expensive. There are many others too.
Have fun, that's what it's all about, Bill.
Well yes implementation is crucial of course... but for first the DAC chip has to be one whose sound I like (me, I like a lot the sound of Crystal chips).
Also, I don't mind opamps at all... but as few as possible and chosen among the (real) best (meaning not necessarily those most popular in forums ).
Also, I don't mind opamps at all... but as few as possible and chosen among the (real) best (meaning not necessarily those most popular in forums
).Thanks for that.
I'm unsure if you read a recent post by amc184? but he's kind of disheartened me in my nad, would have been more honest to say he thinks it's a bit crap.
But, and a big but, I thought that's what it was all about? get something and make it better? most of the enjoyment I get is actually playing with the thing, not sitting there afterwards analysing the output.
The aim is to make it sound better whils't having fun with the iron, but if there is little difference afterwards then so be it, if there's a increase in musical enjoyment, then that's a bonus.
On the other hand, if I want to sit and 'enjoy' the music, then I'll power up mr Boothroyd and 'plonk' a disc in the destiny.
Chow
Hmm, I haven't checked but I doubt that the CS4398 is pin compatible.
Anyway I don't think it's limiting to have the CS4392 and not the CS4398 in this kind of player.
BTW, in my opamp tests I found the LME49720HA to sound quite well paired with the CS4398 -- it was one of my absolute favorites.
Maybe you could try the OPA1612 too.
Anyway I don't think it's limiting to have the CS4392 and not the CS4398 in this kind of player.
BTW, in my opamp tests I found the LME49720HA to sound quite well paired with the CS4398 -- it was one of my absolute favorites.
Maybe you could try the OPA1612 too.
Great stuff, thanks.
Just been looking at the dac supply regs. There's 2, 1 drops the 10v input to 5v (KIA11117S55) and into a KIA1117S33 (down to 3.3v) to supply the D/A.
Thinking of pulling them out and swapping both for a single 3.3v ClassD discrete module, what do you think??
I use the ClassD regs for the opamps and what I thought was the D/A supply, but it's not...... oops.
Don't know well that stuff... I will just say that I don't think the usual regulators are a big limiting factor for sonic quality. Maybe only in extreme high end audio (the sort of thing we usually see as pure craziness)
I would be more concerned about the quality of the electrolytic capacitors in the power supply lines. Upgrading these can be very cost effective. I personally like the Rubycon ZL caps a lot (for their lifetime too).
I would be more concerned about the quality of the electrolytic capacitors in the power supply lines. Upgrading these can be very cost effective. I personally like the Rubycon ZL caps a lot (for their lifetime too).
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