adfinni said:Must have been too much heat from my iron when de-soldering.
Don't leave it in the fire for so long !
poynton said:
Both channels fairly well equally. I've not touched the DAC or anything near it. The noise only came on after adding the external power supplies for clock and fliplop.
So I presume it can be narrowed down to one of:
1 - a grounding problem
2 - noise from reg boards or wiring radiating into a circuit, like op-amps
3 - I've accidentally interfered with clock or divider ccts (I've been careful)
4 - other stuff I'm not clever enough to realise
What do you think?
Simon
rowemeister said:
Yeh, sure thing. I'll ammend my schematic to reflect the exact setup at present, ignoring the latest psu, as that made no difference to the noise levels. Or I could add it anyway with that proviso.
A recording will be a royal pain in the bum but I'll do it if you think it'll help!
Re: Re: Re: Re: Help!!!
Hello there,
Ray I think you are right, now the problem sounds not so evident to me. I still think I miss bass, but maybe the bass the CDP sends can't be given by the small 11L and the Arcam... and that's true I've never listened my discs on a high end system, so in fact I have an idea of what it should sound like, but I don't know how this sounds like in real. I'll cut some parts of the songs to let some of you willing to to try. (maybe fews seconds of 2 songs as PCM makes big files...).
Right now my feeling is : some bass get less volume compared to other freq, but on some other discs it seems they are still present, on some others the drum kit lost is big drum. Only tsiiing ... tsiiing ... no more tsiiing poOOmm tsiiiing poOOmm...
In fact I'm lost...
edit : I'll plug my Philips to see the diffrences...
6h5c said:
Hello there,
Ray I think you are right, now the problem sounds not so evident to me. I still think I miss bass, but maybe the bass the CDP sends can't be given by the small 11L and the Arcam... and that's true I've never listened my discs on a high end system, so in fact I have an idea of what it should sound like, but I don't know how this sounds like in real. I'll cut some parts of the songs to let some of you willing to to try. (maybe fews seconds of 2 songs as PCM makes big files...).
Right now my feeling is : some bass get less volume compared to other freq, but on some other discs it seems they are still present, on some others the drum kit lost is big drum. Only tsiiing ... tsiiing ... no more tsiiing poOOmm tsiiiing poOOmm...
In fact I'm lost...
edit : I'll plug my Philips to see the diffrences...
poynton said:
Hi Andy,
Yes, the more I listen the more seductive this combo (LM6171+OPA627) is sounding. In my setup it beats LM6172 or 2xOPA627 and seems to have the best of both flavours. It also beats LM4562 and 2xAD8065. The sound seems very extended at both frequency extremes with a lot of snap to it. Very nimble bass and a relaxed yet powerful sound. It's quite captivating - everthing I play seems to sound good.
Other people may get different results however - my op-amps are driving the HDAMs, theirs will be driving their interconnects and pre-amps.
I have matched the resistors in the diff. amp to 0.1%. One could lift the DAC end of the first resistors and apply a common signal and fine-tune it for zero output I suppose...
Also, the CRDs are 1.8mA.... pull it down to the -ve rail is presumably the way to go.
I tried it on an OPA2604 years ago in my pre (now it's 2xAD8610 anyway) and it seemed to fix what was wrong and break what was right. Sorted out the highs and f***ed up the bass.
I'll try it soon though and report back.
I tried it on an OPA2604 years ago in my pre (now it's 2xAD8610 anyway) and it seemed to fix what was wrong and break what was right. Sorted out the highs and f***ed up the bass.
I'll try it soon though and report back.
Glenn2 said:
I assume you have read these ....
http://tangentsoft.net/audio/opamp-bias.html
http://www.audioasylum.com/audio/tweaks/messages/31186.html
1.8mA should do OK although they may be a little on the low side.
Andy
SimontY said:
Could be radiation from your clock beating with the 8MHz clock of the uP due to long lead length?
Do you have ferrite beads close to the input/output of the regulators to stop RF ?
Andy
poynton said:
Nope, I have no beads there but now I have ideas, thanks! I think I have a couple lying around I could use. Also I will try to neaten things a little in the player. The other I'll try is cutting out the bleed resistors, as Brent says they could cause oscillation and he feels they're not necessary. Gimme a couple of hours to get home and I'll perform surgery...
Hallo to everyone!
Here is my modded cd63se:
C805/806 Elna Cerafine 100u/25v instead Elna RA-2 470u/16v
C651~654 (HDAM) Elna Silmic 220u/16v instead Elna RA-2 470u/16v
C903/904 Elna Cerafine 100u/25v instead Elna RA-2 100u/16v and NJM211DD (headphone amp)
C508/134/136/151/152 120pf/50v Film caps instead [the same values] Ceramics (red).
16,9 MHz clock (from a cd67se).
Now the sound is wonderfully musical, smooth, warm and deep.
Here is my modded cd63se:
C805/806 Elna Cerafine 100u/25v instead Elna RA-2 470u/16v
C651~654 (HDAM) Elna Silmic 220u/16v instead Elna RA-2 470u/16v
C903/904 Elna Cerafine 100u/25v instead Elna RA-2 100u/16v and NJM211DD (headphone amp)
C508/134/136/151/152 120pf/50v Film caps instead [the same values] Ceramics (red).
16,9 MHz clock (from a cd67se).
Now the sound is wonderfully musical, smooth, warm and deep.
Attachments
Glenn2 said:
Could you describe what aspects are better than LM4562? By how much? I'm still knocked over by the LM4562 and wonder: "There's more?!"
Thanks
adinica said:
Hello!
That's from a light modding, so you can only imagine... no, you can't even imagine 😉
Keep at it. I fully recommend reclocking. And schottky diodes in the psu make it smoother sill. Many other things you can do too.
Simon
adinica said:
Good start. Watch out, you could become like the nutters here!
It looks like you missed a couple important and free upgrades:
Replace C656/C658, and C655/C657 with wire jumpers.
Replace the "fuse" resistors sticking up with wire jumpers in the analog output stages: R613,R614,R615,R616 on the opamps, and if you still use the HDAM, R651,R652,R653,R654. Later on, after a bunch of other mods you can fine tune this by using inductors instead of jumpers.
Next most important are the opamps. Simple plug in replacements are the new and inexpensive National Semiconductor LM4562 (Plastic DIP version) that's currently only available as samples direct from NS. These sound far, far, far better than the stock ones.
Hi adinica.
Glad your happy with the sound, but there are much larger gains to be had. Mainly with installing a new dedicated clock pcb (e.g. audicom superclock 2 cheap off ebay ~£50), new op-amps, removing the crappy HDAM when installign the op-amps, and many other.
I would also recommend you read over the mod list seen on teh first page of this huge thread. Rays list is excellent and will help you out a lot.
I would advise that you remove the headphone circuitry as it is pretty poor sounding, and focus on modding the most important circuits 😀
Glad your happy with the sound, but there are much larger gains to be had. Mainly with installing a new dedicated clock pcb (e.g. audicom superclock 2 cheap off ebay ~£50), new op-amps, removing the crappy HDAM when installign the op-amps, and many other.
I would also recommend you read over the mod list seen on teh first page of this huge thread. Rays list is excellent and will help you out a lot.
I would advise that you remove the headphone circuitry as it is pretty poor sounding, and focus on modding the most important circuits 😀
markk02474 said:
Well if like most here you've removed the HDAM then you may get totally different results to me anyway. I tried various op-amps in an old CD-63 years ago, and the order of merit was totally different with/without the HDAM in circuit. The FET buffer is a very light load for the op-amp. (I'm using a 67SE btw.)
It sounds a bit airier (is that a word? - it is now) at HF and a bit deeper into the bass without being flabby. The LM4562 sounds a little dry by comparison though still very clean and punchy. Sometimes there's a little something you can't put your finger on and easily identify as 'extra this' or 'less that'. It just sounds more right in my system.
There's always taste to factor in as well! It gave me a sound I preferred - may not be 'better', just different.
The ones I consider IN MY PLAYER to all deliver the goods sonically but in different ways are
LM6171+OPA627
LM4562
2x AD8065
2x AD8610
2x OPA627
AD826
LM6172
In my old CD63 I tried AD826, LM6172 and 2xAD825 with and without HDAM - only the AD825 got better without it. The LM6172 was certainly better with it, and the AD826 didn't care!
Glenn2 said:
Hi.
You are right in that the HDAM is a buffer.
I wonder what the system would sound like with the second opamp bypassed NOT the HDAM or replaced with a buffer such as Elantec EL2001 in the link above.(with the HDAM bypassed)
Your findings above probably reflect the relative opamp loading.
Andy