I tried some lm4562s off ebay too never convinced they were real (chinese😱) So i brought some from the usa much better.my offset is pretty equal too no horror shows with amp and speakers.😀Great timing for a Parts Connexion sale!
I double-checked the terrible DC offset readings and confirmed that the problem went away with the FKs back in. I also replaced the LM4562HA op-amps that I got from eBay with ones sourced from Newark (this time using those cool little BrownDog adapters instead of bending the pins). I'd be interested to test it again now, but I'll probably wait until I have some nice Mundorfs to go in place of the FKs. The poor pcb trace in that area can't take much more swapping in and out.
I was wondering - besides blocking DC coming out to my amp, don't the blocking caps also provide a valuable function in protecting the player from getting DC passed into it? If I was to plug the CD player into equipment with a powered output - e.g. on a PC sound card - would it be likely to get damaged without the blocking caps?
alan
The LM4562HAs that I bought from eBay were coincidentally also from China. The one I got for my phono stage recently is an obvious fake and will not touch any equipment of mine on its way to the bin. The two that went into my CD player were from a seller with very high positive feedback (3,000+) and look like the real deal. I don't have any reason to suspect them, but I have swapped them anyway for a pair I got from Newark just to be on the safe side. No listening impressions yet though 'cos my amp's bust.
The one big ball ache modding a player more you do longer it takes to get the board out. need a rethink make it easier.
planning a swop out to my 63ki next.
alan
planning a swop out to my 63ki next.
alan
Any opinions on Mundorf 25v 22,000uF AG for C813, C803, C804? MLSI are a steal right now for $11 at PC, if I can make 'em fit.
They'd be replacing a 4700uF BG STD on C813 and 2200uF BG FK on C803/4. In fact, they'd be the only non-Black Gate electrolytic caps in the entire system except for in the headphone and remote control circuits.
They'd be replacing a 4700uF BG STD on C813 and 2200uF BG FK on C803/4. In fact, they'd be the only non-Black Gate electrolytic caps in the entire system except for in the headphone and remote control circuits.
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The opamp output needs a series resistor for stability into cable capacitance. I usually use 150R. This has the side benefit of giving some protection against connection to low voltage dc like PC microphone inputs (although these are current limited anyway to a few mA)
Any Obbligato explosed and no more adivsed?
No, nothing exploded 😀
Of course, the Obbligato's are very nice caps as well, but I noticed they are also quite large. The smaller values don't come in a lower 200V voltage unfortunately. But if you have room to fit them, I think they are a great and cheaper alternative to the Mundorfs.
Regards,
Ray
An uneven offset is often caused by a supply voltage imbalance
Brent
That's not true...
The offset at the output is ONLY directly influenced by the resistors around it, and the input offset current (Iib) and voltage (Vio) of the opamps. Any differences between the DC offset of the DAC outputs will also contribute. But the supply voltage merely delivers the current that's needed for the opamp to function.
Needless to say that a higher voltage will heat-up the opamp, which will in turn have an effect on these offset values, but that's an indirect thermal effect.
Ray
Any opinions on Mundorf 25v 22,000uF AG for C813, C803, C804? MLSI are a steal right now for $11 at PC, if I can make 'em fit.
They'd be replacing a 4700uF BG STD on C813 and 2200uF BG FK on C803/4. In fact, they'd be the only non-Black Gate electrolytic caps in the entire system except for in the headphone and remote control circuits.
Fit them on short leads, they are awesome caps. There were some pics recently, I think Alan fitted large can TSUPs here too!!
Ray
Supply a opamp with say a +9V reg and a -12V reg. You will get a -ve voltage on the output or vice versa.
Yes of course those other things cause a fault too but often the simplest things cause a problem
Brent
Supply a opamp with say a +9V reg and a -12V reg. You will get a -ve voltage on the output or vice versa.
Yes of course those other things cause a fault too but often the simplest things cause a problem
Brent
Are the mundorfs worth the investment over the tsups, cos im planning a much better job on the ki using only premium quality parts, spowers ,clock and caps and off board psu.Fit them on short leads, they are awesome caps. There were some pics recently, I think Alan fitted large can TSUPs here too!!
alan😀
Basic yes but it is very important and done right those upgrades will outperform lots a little faffy tweaks by a long way. Lee has found this out since coming back to the 63 and doing that way
Brent
Brent
Wouldn,t say basic its a great base to start at a player in the level of tune your page discribes is a giant killer.you would pay many thousands to beat it.
alan
alan
Basic yes but it is very important and done right those upgrades will outperform lots a little faffy tweaks by a long way. Lee has found this out since coming back to the 63 and doing that way
Brent
Definitely, yes.
Lee.
What is funny?
Brent
How many 10k players do you have to hand to A/B?
Are the mundorfs worth the investment over the tsups, cos im planning a much better job on the ki using only premium quality parts, spowers ,clock and caps and off board psu.
alan😀
Without any shadow of a doubt!!!!
I used TSUP's as a cheap cap which is much better than std but the SI's are in another league. I think I've got about 14 pairs now! The cap in the middle of the board is a TSUP but its and every other rail in the player about to get replaced by the 10 you can see in the photo plus a few more! 😀😀
I'm also using them in my phono stage too.

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