[mikaelmark]

Sounds good thanks but I don't plan on dropping +50 bucks to roll 6 caps lol, my friend wants me to go 1K everywhere coz ripple current is highest, you tell me 220 and I planned on going 470 with the highest voltage for better ripple
You want me to go FC & FR, he wants me to go KA & KW, I wanna try Silmic's for the opamp section anyway so there ya go +$50 of audiophool OCD disaster

I' d rather blow that half-benji on furu pure copper RCA sockets for my DAC to match the pair I'll be putting in mstage

"but silver oxide is still more conductive than everything else but silver "

No, oxide is always bad for connection area´s! Hav´nt you (as I) had partially or fully loss of sound because of annoying connectors, and when touching the cable a little, the sound will come back. And old equipment with volume attenuators that will scratch if turning them and if moving them back and forth for a while, they will be a bit quiter when the oxide dissappers a little. Those situations almost always appears because of oxide

Small amount of oxide can be removed with strong alcohol, preferrable about 96% isopropanol or using some Contact cleaner liquid, such as DeOxit or Cardas Contact Conditioner. But those liquid´s should be used with care, because they are conductive and should NOT be used for hight voltage AC wall outlet jacks.

About replacing the four or six caps, a batch of ten pieces of Panasonic FR 470uF, 24V will cost you about $7USD at ebay, incl. shipping. FC are the widely used model, good for for PSU´s, FM are the low ESR model, and some people reporting they are not totally stable. FR are the newer development of FC and should be among the best for this position.

Nichicon KA, KW and FW is intended for audio use, but I´m not shure they will be fine for this PSU position. For example Nichicon Muse KZ are the brand´s top model for audio, but Silmic II should be better.

 

[leeperry]

OK thanks fair enough, did you try to bypass them all will small Wima/Vishay? It apparently yields great results

Well I got those eichmann bullet knock-off's, wish me luck then: http://www.ebay.com/itm/321757909078

I'm also very impressed by how much a shielded power cable matters to Mstage huh

 

[leeperry]

Actually regarding FR my friend said that it's too low impedance and that once amp has warmed up for a few minutes, I should check and see if the regulators run hotter than with stock caps.

 

[mikaelmark]

The FM -series are known to be very low impedance. The FR should be about equal to FC, but a newer serie with the advantage of very low ESR.

I hav´nt noticed any downsides with my four FR 470uF, 25V.

But now I was googled for it, and someone recommend not using the FR in "bridge rectifier area" for an amp. Can someone confirm/declare if this is the case here!? I know they are in the PSU section and positioned after the rectifier diods before the transistors.

http://rockgrotto.proboards.com/thread/7954/panasonic-fc-fr-capacitors

 

[mikaelmark]

They stated to be fine for use in Switched Mode Power Supplies, SMPS-technology.

http://diyaudioprojects.com/Forum/viewtopic.php?f=10&t=3018

https://www.gearslutz.com/board/geekslutz-forum/784070-best-coupling-caps-elna-nichicon.html

 

[mikaelmark]

https://www.computeraudiophile.com/...-mini-review-of-the-singxer-su-1-ddc/?page=18

https://www.head-fi.org/threads/aud...oute-new-devices-opens-up-new-options.822160/

https://penoff.wordpress.com/2017/0...ne-amplifier-part-i-schematic-and-pcb-design/

http://www.diyaudio.com/forums/headphone-systems/204993-capacitors-opamp-power-rails.html

"I do agree that there can be problems when paralleling an electrolytic and a relatively-small cap. But the ESR of the electrolytic isn't usually the problem. Even the "low-ESR" types do not have extremely-low ESR. The small cap's ESR, on the other hand, CAN be a potential problem, such as when a film cap is used there. With its tiny ESR, its capacitance can form an under-damped HF resonance with any stray inductance, such as that of the electrolytic."

"For PSU filters I prefer the newer Panasonic FR (or Nichicon UHW if I want bigger values like 4700uF @25V).
Just be careful not to put them (or any other low ESR cap) after a series regulator like LM78xx or LM317. They will oscillate."

 

[listen4joy]

i just want to say thanks to mikaelmark that helped me a lot to build this amp beofre few months, with good quality parts that will be sound good and close to the original one.
although i still haven't the chance to compare them one by one..for the price i really satisfied the combo with my HD800 +(SDR MOD), the main differnces will be when you will switch chipamps to tune the sound signature that will fit to your own taste, i only tried 2 of them, anyway i would like to share my own amp to incourge others to build this one and the result can be pretty good.

 

[SONYES]

i just want to say thanks to mikaelmark that helped me a lot to build this amp beofre few months, with good quality parts that will be sound good and close to the original one.
although i still haven't the chance to compare them one by one..for the price i really satisfied the combo with my HD800 +(SDR MOD), the main differnces will be when you will switch chipamps to tune the sound signature that will fit to your own taste, i only tried 2 of them, anyway i would like to share my own amp to incourge others to build this one and the result can be pretty good.

Outstanding in your success and stubbornness
Appreciate
Too bad I do not have the original to compare

There is no doubt that the design of the original BCL is one of the best things
To HD800

 

[SONYES]

THANK YOU

 

[Mad Max]

The FM -series are known to be very low impedance. The FR should be about equal to FC, but a newer serie with the advantage of very low ESR.

I hav´nt noticed any downsides with my four FR 470uF, 25V.

But now I was googled for it, and someone recommend not using the FR in "bridge rectifier area" for an amp. Can someone confirm/declare if this is the case here!? I know they are in the PSU section and positioned after the rectifier diods before the transistors.

http://rockgrotto.proboards.com/thread/7954/panasonic-fc-fr-capacitors

The rectifier diodes are right after the transformer, not after the regulators like those 470uF capacitors.

If I understood correctly, the line out is the same as the headphone out?
Is this a common industry practice? From what I understood, pre out and headphone out should be different as you don't want to double amp the power amplifier.

The preamp output, or "pre out" as it is sometimes labeled, should be the same thing as the "headphone out", or "HP out", as far as I know, in most amplifiers that have these.
That is precisely the signal that you want for a power amplifier, as the power amplifier on its own is missing the preamp. An integrated amplifier has both in one unit. I don't know if this is "double-amping" (probably not), but that's how it is normally done. "Double amping" should be something like chaining two preamps together before the power amp.

 

[penmarker]

Quote:

6. This is trimmer pot. With it you can tune ONLY POSITIVE VOLTAGE (LM 317) and lower your DC offset.

Hi, this seems a bit peculiar.
I've revisited my amp build and I realized mine doesn't have the trimmer.
Maybe different board version? Mine is straight from AliceMagicBox and not eBay or AliExpress.

 

[leeperry]

so OPA1622 is indeed a major winner but even with no input connected I get 28+40mVDC offset at 10X gain, hell SQ is too good I don't care hah. I was told by a discrete opamp manufacturer that mstage would most likely always become a DC cannon with discrete opamps because "they pull a couple uA of bias current that can cause offsets that then get gained up by the system gain. Lowering the gain will help" and I guess 1622 isn't too happy either but man this chip is indeed the sheer winner we were promised, 145mA output

DC offset is 2+7mV at 1X gain but sound is far less percussive ><

Regarding those 470uF caps, I think I'll just go with 6X https://www.digikey.com/product-det...onic-components/EEU-FR1J471/P15415-ND/3072295

 

[mikaelmark]

Hi, this seems a bit peculiar.
I've revisited my amp build and I realized mine doesn't have the trimmer.
Maybe different board version? Mine is straight from AliceMagicBox and not eBay or AliExpress.

This mod is an optional upgrade, similar way as replacing two of the four resistors with diodes (as I have done in mine).

I assume this potentiometer allows to trim more exactly the voltage you want.

 

[mikaelmark]

so OPA1622 is indeed a major winner but even with no input connected I get 28+40mVDC offset at 10X gain, hell SQ is too good I don't care hah. I was told by a discrete opamp manufacturer that mstage would most likely always become a DC cannon with discrete opamps because "they pull a couple uA of bias current that can cause offsets that then get gained up by the system gain. Lowering the gain will help" and I guess 1622 isn't too happy either but man this chip is indeed the sheer winner we were promised, 145mA output

DC offset is 2+7mV at 1X gain but sound is far less percussive ><

Regarding those 470uF caps, I think I'll just go with 6X https://www.digikey.com/product-det...onic-components/EEU-FR1J471/P15415-ND/3072295

Just take a note the diameter size of those; 0.492" Dia (12.50mm). As they are rated 60V, they can be quite big, but I think they should fit to the board - but please measure before you buy.

25V and 35V´s diameter is only 10mm, and they will absolutely acceptable in this position. If you chose 35V, you will be totally on the safe side of both Voltage and size. They´re also 2/3 of the price. The only negative are the estimated life span @ 105 degrees Celsius will be 8000 hours instead of 10000 hours for 63V.

https://www.digikey.com/product-det...c-components/EEU-FR1V471B/P15391CT-ND/3072271

 

[leeperry]

Well the higher the voltage rating the higher the ripple and 12.5m will fit everywhere as far as I can tell. I'm kinda looking for game-enders, not interested in saving a few bucks or rolling caps several times in a row. My friend wanted me to go much higher than 470uF but FR is apparently prone to oscillation so I'd rather stick to the original value(which is already overkill FWIR).

I will also have to try that wima bypass trick under the PCB as it's also supposedly a major winner and maybe upgrade them to vishay's later on but man you gotta hear OPA1622

I'll also try OPA1688 for the hell of it