I recently upgraded from an old Nad C530 to a new 565. First impressions were great. More detail, sharper but right. Then I played some older CD's. Arrrrg. What you learn real quick is just how bad the old CDs were. Early Beatles? 14 bit Sony transcriptions of a bad tape.
I need a switch. Good and bad CD. The older NAD kind of masked the problems of really poor CD's. Of course, it did not do the detail of better CD's.
Transformer? Analog low pass? Tube? What ideas are out there? Oh, it sounds just about like my external DAC. The answer is not a thousand dollar DAC.
I need a switch. Good and bad CD. The older NAD kind of masked the problems of really poor CD's. Of course, it did not do the detail of better CD's.
Transformer? Analog low pass? Tube? What ideas are out there? Oh, it sounds just about like my external DAC. The answer is not a thousand dollar DAC.
Try a simple one or two transistor FET buffer stage to add a bit of even harmonic distortion to the mix.
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Not familiar with the NAD but it might be worth looking at the output stages of the player. It could be worth considering different opamps (assuming it uses something like 5532's) that can offer subtle but real improvements to sonics. That wouldn't spoil the sound you get from better CD's either... you might like them even more.
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Not familiar with the NAD but it might be worth looking at the output stages of the player. It could be worth considering different opamps (assuming it uses something like 5532's) that can offer subtle but real improvements to sonics. That wouldn't spoil the sound you get from better CD's either... you might like them even more.
Actualy, they have some of the latest parts. This is their $800 unit. My old C530 had 5532's. Op amps don't make this big a difference. How well they are used does.
No, like I said, a well mastered CD sounds better. Clean, crisp, accurate. A bad CD is more clearly bad. Truth can hurt. So I am looking to DEGRADE it's performance optionally. A buffer with limited BW may be a reasonable idea. A couple poles of LP may help. 18K maybe?
No, like I said, a well mastered CD sounds better. Clean, crisp, accurate. A bad CD is more clearly bad. Truth can hurt. So I am looking to DEGRADE it's performance optionally. A buffer with limited BW may be a reasonable idea. A couple poles of LP may help. 18K maybe?
An HF shelf might smooth things a little. Alternatively, try a Bessel filter - very round corner so more amplitude loss but a good approximation to linear phase so no timing distortion. From memory, a double-pole (e.g. Sallen-Key) filter should have Q=1/sqrt(3) for Bessel response (Q=1/sqrt(2) is Butterworth i.e. maximally flat).
I think you are just finding out that your C565 is not as good as it's cracked up to be. Whenever I do an evaluation of the sound of a player/dac that I've upgraded or just checking out, or an output stage I've designed, I always play not just my best recorded cd's, but also certain of my worst. A unit that sounds great on a great recording isn't necessarily great. A bad recording can reveal a lot about the real quality of the unit. For me to consider a unit/circuit really great, it has to sound great with great recordings, and make bad recordings sound no worse than they actually are. My personal experience with players using Wolfson dacs, like your C565, is that they have a metallic, ringing character to the top end that does not become obvious until you play a cd that has top end that is excessive or less than smooth, at which point the Woflson dac chips I've heard so far have chased me out of the room. Fast. And this has been the case even when I have upgraded the heck out of the output stages & power supplies to give the dac chip it's best chance of sounding good. I frankly think they are just plain awful chips. I think people get dazzled by how clean & clear they sound on a great recording, and are misunderstand that the bad sound they hear from bad recordings is actually being made a lot worse by the dac.
Nicely put Stephen...
it's also very much how a system as a whole sounds and comes across to the listener. It doesn't matter what technical attributes all the components may have. If you don't like what you hear then its not doing its job.
The amplifier used can make a huge difference in the "whole system" concept too.
it's also very much how a system as a whole sounds and comes across to the listener. It doesn't matter what technical attributes all the components may have. If you don't like what you hear then its not doing its job.
The amplifier used can make a huge difference in the "whole system" concept too.
Hmmm. I had not heard that criticism of the Wolfson chips on the higher end. That is about how I would describe what I am hearing. It also could be the speakers being asked to do things they had not before. I'll plug in my external DAC. It has a PCM1793/DIR9001 chipset in it. It's power supply is not the best and I am suspicious of some of the analog. ( $100 Chinese special) It is better than than my last two CD players. The preamp is a Nak CA-5 feeding my modified DH120 amp.
Where I want a unit to make the best of a good recording, as in be accurate, I don't consider a unit that masks things enough to make a bad recording better to be great. That is exactly what I want to do, but have an option; clean or masked. Breadboarding up a quick little filter should not be too hard. Of course, one reason I got this one was to get a one year warrantee. It IS an NAD.
All is not lost. My absolute requirements were it was a CD player, so it starts fast, and it fits on a 12 inch shelf. If I have to go to an outboard DAC, so be it.
Where I want a unit to make the best of a good recording, as in be accurate, I don't consider a unit that masks things enough to make a bad recording better to be great. That is exactly what I want to do, but have an option; clean or masked. Breadboarding up a quick little filter should not be too hard. Of course, one reason I got this one was to get a one year warrantee. It IS an NAD.
All is not lost. My absolute requirements were it was a CD player, so it starts fast, and it fits on a 12 inch shelf. If I have to go to an outboard DAC, so be it.
You have what I consider the best sub-$2k solid state preamp around in that CA-5. Good choice, which only needs soft recovery diodes to be about as good as it can get. The DH120, though, is certainly an amp that would be, without major redesign, "excited" to be harsher by a dac that has eccentricities in the top end like the Wolsons(IMO). A Nak PA-5(w/LF corner freq 10uf film enlarged by addition of at least 150uf/50v Nichicon lytic to remove subsonic BW limit) would be a huge improvement on a low budget, and can be relied upon to NEVER exaggerate any top end nasties.
Have to say, I would not touch an NAD piece with a ten foot pole, speaking as a 30+ year exp servicer, knowing how unreliably virtually every piece they make is built, due to combo of lackluster engineering and severe corner-cutting for cost.
Have to say, I would not touch an NAD piece with a ten foot pole, speaking as a 30+ year exp servicer, knowing how unreliably virtually every piece they make is built, due to combo of lackluster engineering and severe corner-cutting for cost.
Stephen,
Well, I would agree fully, but the 120 has a vastly improved power supply, Exicon outputs, cap replacements, and the compensation is moved from the VAS output to Miller compensation. Inputs are matched to better than 1% and the other 4 compensation circuits are removed. Let me tell you, it was a real pain to get it stable and match the slew rates of the outputs. Is it great? No. It is darn good. At least until I can afford to bid on a PA-5 it will do fine. As I have an ST-7 tuner, why not? It is just my little office system. Maybe I should have bid higher on that last Linn.
Anyway, just did a careful listen to my BB DAC and the NAD. The BB happens to have an analog-in bypass so it was a simple A/B. Listening to the Grado's, I would not bet I could hear the difference. Granted my BB DAC is a Chinese DAC/phones special (MUSE) and it is not world class, but it was a darn sight better than the old C520. I never really compared it to my big Rotel. I need to get on with my speaker projects. Embarrassingly, I still have Kef Q1's here. I build a lot better. I just have to get around to it. I have four speaker projects going.
I have to agree with the questionable NAD quality. 3 of 5 I have owned have failed. The C520 was really just too long in the tooth. Can't really call it a failure. But it HAD to fit on a 12 inch shelf. The only other one I found was a used Arcam. I really know nothing about them other than being respected. I will say, 2 of 4 HK's have failed and every single Sony, every one, failed. Never a failure in a Denon, Marantz, Nak, Rotel, Hafler, B&K, Luxman, Kenwood, Pioneer, Sanyo, JVS, MXR, DBX, Behringer, KLH, Eicho, Knight, Heath, Thorens, Philips, Yamaha, and , hmmm. what else have I had? Oh, I had a CM Labs amp that even the factory could not get stable. Gave up after three times. I do think NAD has gotten a bit better, or at least I am telling myself that.
One of these days I'll look inside the CA-5, but as right now I don't even have a sub, the LF corner is not an issue. I really do need to look at the power supply. Anything this old needs caps, and I have had very good luck with diodes lowering the noise floor.
I guess the message here is the CD is OK. I need to address the speakers. I am a bit surprised none of my bottle head friends have suggested a tube buffer. =D
Well, I would agree fully, but the 120 has a vastly improved power supply, Exicon outputs, cap replacements, and the compensation is moved from the VAS output to Miller compensation. Inputs are matched to better than 1% and the other 4 compensation circuits are removed. Let me tell you, it was a real pain to get it stable and match the slew rates of the outputs. Is it great? No. It is darn good. At least until I can afford to bid on a PA-5 it will do fine. As I have an ST-7 tuner, why not? It is just my little office system. Maybe I should have bid higher on that last Linn.
Anyway, just did a careful listen to my BB DAC and the NAD. The BB happens to have an analog-in bypass so it was a simple A/B. Listening to the Grado's, I would not bet I could hear the difference. Granted my BB DAC is a Chinese DAC/phones special (MUSE) and it is not world class, but it was a darn sight better than the old C520. I never really compared it to my big Rotel. I need to get on with my speaker projects. Embarrassingly, I still have Kef Q1's here. I build a lot better. I just have to get around to it. I have four speaker projects going.
I have to agree with the questionable NAD quality. 3 of 5 I have owned have failed. The C520 was really just too long in the tooth. Can't really call it a failure. But it HAD to fit on a 12 inch shelf. The only other one I found was a used Arcam. I really know nothing about them other than being respected. I will say, 2 of 4 HK's have failed and every single Sony, every one, failed. Never a failure in a Denon, Marantz, Nak, Rotel, Hafler, B&K, Luxman, Kenwood, Pioneer, Sanyo, JVS, MXR, DBX, Behringer, KLH, Eicho, Knight, Heath, Thorens, Philips, Yamaha, and , hmmm. what else have I had? Oh, I had a CM Labs amp that even the factory could not get stable. Gave up after three times. I do think NAD has gotten a bit better, or at least I am telling myself that.
One of these days I'll look inside the CA-5, but as right now I don't even have a sub, the LF corner is not an issue. I really do need to look at the power supply. Anything this old needs caps, and I have had very good luck with diodes lowering the noise floor.
I guess the message here is the CD is OK. I need to address the speakers. I am a bit surprised none of my bottle head friends have suggested a tube buffer. =D
It's the PA-5 power amp that has the too-smal LF corner cap. Nakamichi was very paranoid about their own first run of stasis amps & receivers(which Nak designed, not Nelson), so the first PA-5 & PA-7 had the subsonic cutoff & oversensitive protection mute circuits(easy 2 resistor changes to cure that bit), but are otherwise terrific even without further upgrading.
You will NOT need to replace ANY caps in the CA-5 for at least another 20 years, and would be wise to leave them alone. All of the lytics are top shelf Nichicons, rest are film caps. Literally only the rectifiers are the only place for any meaningful upgrading. Four soft recovery diodes, some Triflow spray into the controls, and you're done.
You could make a damn nice all-Nak system by adding, for usually around $100, a CDP-2A. Uses a surprisingly well implemented TDA1541A w/simple & easy to upgrade output stage, and is a lovely sounding player, with a cheap but very reliable(other than periodic loading belt & tracking rail lub every 10 years or so) Sony mech. It's a great little player. Other really good one in same range of cost/sound is the CDPlayer4/CD-4(same player, different front panels), which uses the venerable AD1864 dual 18bit r2r ladder dac, the better version of the AD1865 used in the Audio Note dac & so many others. Also has a very simple output stage for easy upgrading(although the opamp is a SIP package that requires an adapter to install an SOIC-8 packaged nicer opamp, e.g., OPA2134UA), and damn nice sound in stock form, and essentially same Sony mech as the CDP-2A. Either one will sound really sweet on good recordings, and still very listenable on bad recordings, because they intrinsically don't suck.;-)
You will NOT need to replace ANY caps in the CA-5 for at least another 20 years, and would be wise to leave them alone. All of the lytics are top shelf Nichicons, rest are film caps. Literally only the rectifiers are the only place for any meaningful upgrading. Four soft recovery diodes, some Triflow spray into the controls, and you're done.
You could make a damn nice all-Nak system by adding, for usually around $100, a CDP-2A. Uses a surprisingly well implemented TDA1541A w/simple & easy to upgrade output stage, and is a lovely sounding player, with a cheap but very reliable(other than periodic loading belt & tracking rail lub every 10 years or so) Sony mech. It's a great little player. Other really good one in same range of cost/sound is the CDPlayer4/CD-4(same player, different front panels), which uses the venerable AD1864 dual 18bit r2r ladder dac, the better version of the AD1865 used in the Audio Note dac & so many others. Also has a very simple output stage for easy upgrading(although the opamp is a SIP package that requires an adapter to install an SOIC-8 packaged nicer opamp, e.g., OPA2134UA), and damn nice sound in stock form, and essentially same Sony mech as the CDP-2A. Either one will sound really sweet on good recordings, and still very listenable on bad recordings, because they intrinsically don't suck.;-)
I thought the newer Nak's were mostly Sherwoods, low end. It would be nice to have a matched system. I never have. Shelf depth is still the limit for a CD. An absolute limit. I worry about older CD's as over time, the laser gets weak.
I was pretty sure the 5 and 7 were both Papa's designs, as were the Adcom 5x5 series, which I don't care for at all. I had a B&K instead, but even it failed my wife's hyper hearing test so I sold it before I figured out it was the speakers that were the root of the problem. The magic here is the old Rotels were designed to work on mid-fi speakers and mask a lot of the tweeter issues. ( VAS output compensation mostly) I got "schooled" quite a bit in the lounge and got to understand a bit about the input filters and their effect on distortion and more on stability and methods of compensation that my poor brain can hold. Eye opening.
I see an old L-11 Levinson and have seen several Linns go for what looks like reasonable money. I just don't know anything about them. I only need 50W or so. Reputation is not reliable. I picked up my hearts delight Creek for my bedroom system and am pretty disappointed. Good not great, but it cost great. I am looking to do a step above what I have. I guess a Parasound 1200 is my top amp right now but the modified Hafler is better than one might think. I don't want a 200W monster in my office. I have had no luck in borrowing a Halo A23. I finally heard a Bryston and was not impressed.
I spent many a year in failure analysis and looked at caps in great depth. No electrolytic really can last over 10 to 15 years. They spec 8. Of course, it it was stored in a hot warehouse, less. If one is 20, it is bad. Period. I know many don't believe me and I am not trolling for a big discussion. Films are just fine.
Anyway, I'll check the physical dimensions of the CDP2A and CD-4 and see if it is viable. A bit of PS and output work is cake.
I was pretty sure the 5 and 7 were both Papa's designs, as were the Adcom 5x5 series, which I don't care for at all. I had a B&K instead, but even it failed my wife's hyper hearing test so I sold it before I figured out it was the speakers that were the root of the problem. The magic here is the old Rotels were designed to work on mid-fi speakers and mask a lot of the tweeter issues. ( VAS output compensation mostly) I got "schooled" quite a bit in the lounge and got to understand a bit about the input filters and their effect on distortion and more on stability and methods of compensation that my poor brain can hold. Eye opening.
I see an old L-11 Levinson and have seen several Linns go for what looks like reasonable money. I just don't know anything about them. I only need 50W or so. Reputation is not reliable. I picked up my hearts delight Creek for my bedroom system and am pretty disappointed. Good not great, but it cost great. I am looking to do a step above what I have. I guess a Parasound 1200 is my top amp right now but the modified Hafler is better than one might think. I don't want a 200W monster in my office. I have had no luck in borrowing a Halo A23. I finally heard a Bryston and was not impressed.
I spent many a year in failure analysis and looked at caps in great depth. No electrolytic really can last over 10 to 15 years. They spec 8. Of course, it it was stored in a hot warehouse, less. If one is 20, it is bad. Period. I know many don't believe me and I am not trolling for a big discussion. Films are just fine.
Anyway, I'll check the physical dimensions of the CDP2A and CD-4 and see if it is viable. A bit of PS and output work is cake.
CD4 is over 12 deep. I wonder how hard it would be to move the cables and power cord to the side and lop half an inch out of the case. They are pretty old, do they play CDR?
I guess I could be looking at smoother external DAC's too. About all I know is my cheap one is better than a lot of CD players, and there is more snake oil than in a cable store out there. I probably should shut up and send more money to Seas where the big payoffs are. Paint is drying so I have time to get in trouble.
I guess I could be looking at smoother external DAC's too. About all I know is my cheap one is better than a lot of CD players, and there is more snake oil than in a cable store out there. I probably should shut up and send more money to Seas where the big payoffs are. Paint is drying so I have time to get in trouble.
Speaking of Adcom, the GFA535II is a very, very cheap($125-150) & common amp that is a HUGE bargain, and doesn't take much work to make quite superb. And it's reliable as hell. Completely dual mono, but for the power cord sharing, and the best sounding amp, I think, that Adcom ever made. Always keep one around as a back-up/loaner amp.
I've been a service pro for >30years, and I can tell you that even a 1980 piece can be relied upon to have any Nichicon caps still in perfect health 99.9% of the time. I can still count on one hand the number of defective Nichicons I have seen in all those years, that weren't subjected to >50% over-voltage for years(literally). Not about that brand, but I work on RCA mic preamps from the mid 1930's very frequently, and you would not believe the number of chassis can lytics for HV supply that turn out to be still good & usable(though I don't leave them in). I also work on a ton of McIntosh tube gear from the 50's up to 1968, and they have at least good HV cans more than 90% of the time. Anyway, if you replace lytics in the CA5, at least do it the justice of using equal or better grade Nichicons.
It would be odd, but simple enough to side-mount the output jacks in a CDP2 or CD4. For rational access, you'd have to cut a section of of the top bonnet so you could then mount the jacks on the bottom chassis' sidewall. At least you wouldn't be hacking something worth a mint. The Sony lasers used almost never get weak or fail(at least 85-90% of the time in my rather prodigious experience with them), and can play cdr no problem.
I've been a service pro for >30years, and I can tell you that even a 1980 piece can be relied upon to have any Nichicon caps still in perfect health 99.9% of the time. I can still count on one hand the number of defective Nichicons I have seen in all those years, that weren't subjected to >50% over-voltage for years(literally). Not about that brand, but I work on RCA mic preamps from the mid 1930's very frequently, and you would not believe the number of chassis can lytics for HV supply that turn out to be still good & usable(though I don't leave them in). I also work on a ton of McIntosh tube gear from the 50's up to 1968, and they have at least good HV cans more than 90% of the time. Anyway, if you replace lytics in the CA5, at least do it the justice of using equal or better grade Nichicons.
It would be odd, but simple enough to side-mount the output jacks in a CDP2 or CD4. For rational access, you'd have to cut a section of of the top bonnet so you could then mount the jacks on the bottom chassis' sidewall. At least you wouldn't be hacking something worth a mint. The Sony lasers used almost never get weak or fail(at least 85-90% of the time in my rather prodigious experience with them), and can play cdr no problem.
Might just pick up what I can there. It would be fun to work over the 535 and one of my 951's to see who wins. Of the series, if I can remember back that far, they were the smoothest. The big 565 the stores always pushed sounded "ballsey" but not smooth. Fine for a sub I guess. Mark I of the 535 is a tad different from Mark II. Which has better promise?
Me have torch. Cut anything. Ugg. As long as the board is not edge to edge, no problem. Cutting a board in half and folding it is a pain. Been there, done that.
Me have torch. Cut anything. Ugg. As long as the board is not edge to edge, no problem. Cutting a board in half and folding it is a pain. Been there, done that.
Good points. Just checked the schematics again. 535 had single outputs, 535II is shown with three. I am going to hear about it, but I'll will grab one.
Stephen, You mention that the PA-7 has a two resistor mod in the protection circuit. I am tackling a PA-7 for a friend right now that has the off-board protect mod, though I don't have any schematic info on it to know what it is or does. Some burned resistors in one channel have been replaced with wrong type resistors and one has burned again since this change. I'm seeing what I consider some real odd stuff going on! The 4.7k ohm, 1/2 watt CLIPPING LED resistors, R143 and R144, have been replaced and there is evidence that there was considerable overheating on both. The 1.8k ohm, 2 watt PROTECT RELAY resistor has been replaced but is burned again! Static tests of the transistors and diodes on this board did not show any shorted or open junctions. I did find one thermal fuse open on the LIMITER circuit. And I al;so have found one 1 ohm, 2 watt Q216 emitter resistor open! So, I've got a bunch of issues and weary from scratching my head! Any help ir ideas?
Honestly, sounds like there is so much going on there, bad service work causing damage & more bad service work & god knows what else, that I would have to see the amp in person to be of any real help. Sounds like something where I'd have to spend hours going through every inch of it.
The add-on board for the protection circuit was on every PA-7 that I've ever seen and is in my original service manual for it, but only later PA-5's & not in it's service manual. It was seemingly for better thermal tracking, but it really had no practical effect of any value, so I don't ever care whether it's there or not. Either circuit version needs those couple of resistor value changes in each channel to prevent premature overcurrent sense muting.
The add-on board for the protection circuit was on every PA-7 that I've ever seen and is in my original service manual for it, but only later PA-5's & not in it's service manual. It was seemingly for better thermal tracking, but it really had no practical effect of any value, so I don't ever care whether it's there or not. Either circuit version needs those couple of resistor value changes in each channel to prevent premature overcurrent sense muting.
There is a good bit wrong, but at least each is in a distinct area and neither seems to affect the other. There are 4 limiting resistors and thermal fuses. Only one is bad. Bingo. One trouble cleared. I have replaced the 1 ohm resistor and its accompanying output transistor. Since the output transistors are all connected to common base feeds, common emitter or collector "rails,"I I also replaced the corresponding transistor. I hope to be able to say BINGO another trouble cleared. Right now my quanddy is wbat has caused the resistors to cook! They seem to be adequately sized for the load, but barring hivh rail voltages, I don't get it! The transistors Q230 &I Q231, Q235 &I Q236 all I check ok. I do plan to replace them anyway. Any thoughts anyone?
What do folks think about trying a Music Fidelity buffer? I have never caught the glass bug, but what the heck? Does it do anything I can't do with just a LP filter? Do I just need to mask the top of bad CD's because the new stuff is letting it through, or is it just plain harmonic distortion that the higher BW analog happily passes along? I have not checked if the schematic is available. Sometimes current production is pretty controlled.
Too many projects to take on shortening the Nak cabinet. At least for now. Holding off on the Pa5, modifying a 535 or building an F5. I still have a project waiting to compare about 10 CCS implementations based on what I learned here and several weeks of Spice modeling. Finding fast fets is the issue. I want to know more about Linn, Music Fidelity, Arcam, Naim and other higher end smaller amps. I have never had an amp with regulated rails. Are they really that much better? I need to build a decent crossover and a couple power supplies. Regulators seem harder than is obvious.
Too many projects to take on shortening the Nak cabinet. At least for now. Holding off on the Pa5, modifying a 535 or building an F5. I still have a project waiting to compare about 10 CCS implementations based on what I learned here and several weeks of Spice modeling. Finding fast fets is the issue. I want to know more about Linn, Music Fidelity, Arcam, Naim and other higher end smaller amps. I have never had an amp with regulated rails. Are they really that much better? I need to build a decent crossover and a couple power supplies. Regulators seem harder than is obvious.
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