Marantz CD63 & CD67 mods list

Re: Re: ...lobs hand grenade...

Glenn2 said:
I said on this thread t'other day that I was warming to it but I've changed my mind again (sorry Simon :D).

It really depends what you're listening to... but sterile is my overriding impression.

That's the main reason why don't like the BB op-amps. I prefer AD8610 over OPA627 for example.

Glenn

lol, you'd think I designed them or something! :D

I have 4 LM4562 in my system right now and perhaps it's too much, I'm not sure yet. Either way I know that going discrete is the ultimate in the CD63. OPA627 I found extemely musical, but once I'd heard this new level of detail and accuracy it would seem crazy to take a step back in fidelity. I've heard OPA2134, 2132, 2604, OPA627, LM6172 and these 4562 and the most 'musical' was 627 (has to be in inverted commas!), by a safe margin.

I think it's crucial to have everything else right to enjoy these op-amps. For example I made a change to my speakers recently and the sound has become quite cold and grating at times, but I'm holding out till I get some new parts to try something.....getting sidetracked here! The point is the changes should've been small (I reckon) but before the sound was warm with stunning bass weight - stuff like Money For Nothing sounded so perfect! And now Dire Straits isn't much fun to listen to. I think an accurate sounding op-amp like this lets you hear faults elsewhere very well. Just my 2p, feel free to disagree.

Simon /being aurally assaulted by Elton John!
 
Re: Re: Re: ...lobs hand grenade...

SimontY said:


Simon /being aurally assaulted by Elton John!

We've heard about Elton's tantrums:clown:

opamps seem to have a brand signature.
If you like the sound, it's the best for you.

Discrete outs have diffference in sound, Fet or Bipolar.

I prefer Fet's???????????????????? but

I prefer the equipment to just produce the signal that is provided, nothing added, nothing lost.
let the music speak for itself, good or bad.

allan
 
shepperd said:
woe is me:confused: this is making me crazy! I have one of Brent's 67's. I put some 627's with high hopes, end up totally disinterested, order 4562's and now I hear they're a disappointement! I should have left well enough alone, now I don't know where to turn! I'm going to be forced back to vinyl:bawling:


Don't fret - you'll probably love it. Most people seem to have eargasms when they hear it.
 
I don't want to abuse your patience (I can see Brent smiling;)) but would you treat me as a bewildered, rather slow-witted newbie who has to be led by the hand (it's good for your egos):
Brent used the bb2134 originally and I liked them but got that awful itch so bought a pair of 627's. As I already posted, I probably did them a mischief by first plugging them in wrong way round (maybe this accounts why I don't like the sound?). Don't ask me how and don't tell me to put the others back cause I crapped them getting them loose. I didn't hear about the caps
(hey this thread is hours and hours of reading!) So if you were really the gentleman that I know you to be
:angel: you will send or paste a nice couple of hi rez pics for me to ponder (you can hold the soldering iron too if you want)! Would these caps apply equally to the 4562's??? Og God why don't I ever leave well enough alone??? That would make for a good DIY epitaph.
 
Good evening guys,

I also find strange the turn back about the LM4562... I don't have time and any wish to listen to opamps for hours, and the simple aim of my mods is really reached with these, better than my former AD8620. If I derserve a better sound I would have bought an overall better system. I think too many people like them and now It's better to say you don't but Glenn who always had strange taste ;)
As one of the most stupid about electronics and with the less good amp/speakers I find the LM4562 fantastic, and very handy direct fit. I do hope a tube high class CDP is far better...

Anyway, My question was about the Flea's PSU (Martin are you around?): mine delivers 17.88V, when the Flea's manual says "minimu 18V" and a "minimum minimum 17.6V"... I'm between the minimum and the minimum minimum... (you see why LM4562 fits me?)

Thanks...
Shepp, still want a pair of LM4562? ;) The caps are between pin 4 and 8, under the PCB is nice, I have MKS2 0.1µF there but I was advised (Simon) my 1µF will do better.
 
Anyway, My question was about the Flea's PSU (Martin are you around?): mine delivers 17.88V, when the Flea's manual says "minimu 18V" and a "minimum minimum 17.6V"... I'm between the minimum and the minimum minimum...
Right here :)

Don't worry that shuld work OK.

The 17.6v figure is the lowest that is guaranteed to work with tolerances of parts - but not the raw PSU - taken into account:

7812 puts out 12.0v nominal, raised from ground by the LED - 1.95v actual, say 2V = 14.0v;
7812 dropout needs to be 2.2-2.5v min at low currents;
Gyrator portion drops 0.65v+ small amount through bias network to drive BC547. How much? well it's the output current - say 20mA - divided by Hfe, say 300 (pessimistic for a BC547C at 20mA). That's 67uA, or 0.67V across the 10K biasing resistor.

So we need (14.0+2.5+1.3v) input, 17.8V, to guarantee it will work. In fact, because the BC54x will have a Hfe of c.400 at these currents, most LM7812s are actually about 11.9v to avoid exceeding their rated voltage (and fwill work with 2.3v overhead at 10mA output) and the LED voltage reduces at -2mV/degreeC, 17.6 will work - always, but that's why it's given as 'minimum minimum'; it gives no allowance for variation in the output of the raw PSU.

If you're worried that your implentation is a bit marginal, then monitor the output from the 7812. It should be constant to two decimal places at (around 13.9v, +/- a little bit). If you see it wandering by 10mV or more over a few minutes then it has insufficient voltage input, and the fix is either more raw input, or reduce R1 (say to 5K ) and try again.
 
Almost to 6000
It's all you fault Ray,
well almost, plus a few others:clown:

there was a good question from Glenn2
has anyone tried the zapfilter2????

It does look interesting, discrete and no output cap also balanced:D
problem is smd's:(

the schematic's available, might see about doing a version for myself.

allan

ps i do understand the layout will not be as good as the original but
 
so who got it ?

ME!!


==========================================

Hello to all contributors to this great thread.

It has been a credit to all for the lack of backbiting etc. and the very good natured responses even when some of the questions have been from inexperienced DIYers.

See you at the UK DIYAudio Fest?

Andy