[raoultrifan]

For AKG K701, Hifiman HE-560 or other hard-to-drive cans I feel that Matrix HPA-3B is indeed an improvement, same for 8...16 Ohms IEMs, due to the higher impedance of the ASUS E1, but for normal sensitivity headphones the internal headmap of E1 is pretty good.

Internal headamp is based on LME49720 and LME49600, so it's quite "contemporary".

 

[mBTX]

(Did a couple searches in this thread for my issue but came up empty.)

I run a balance M-stage amp off of the XLR's in my E1. When I adjust (and ONLY when I adjust) the volume I get a crackle. It is not present on the hp amp side nor the RCA output.

Is this a known isssue?
Is there a fix for this?
Any advice would be great.

 

[raoultrifan]

When I adjust (and ONLY when I adjust) the volume I get a crackle.

It’s from the potentiometer, it got old. You need to clean it with spray for electrical contacts (or isopropilic alcohol and oil) or swap it for a new one (very hard to find a 4-gang pot).

You could also use the pot. to the max. and adjust volume from the Matrix.

 

[mBTX]

Would I be correct in assuming that that pot is a (combined) "pair" of 2 10k pots that simultainiously controls both left and right channels? Or does it have something to do with how this amp achieves its "balance"? I ask because I'm wondering if I wired 2 decent stereo pots up to the main vol. if it would give me L/R balancing. A couple of these perhaps? https://www.hificollective.co.uk/potentiometers/tkd-2cp-601s-potentiometer.html

Either way, I will start with the cleaning method first.

 

[raoultrifan]

Would I be correct in assuming that that pot is a (combined) "pair" of 2 10k pots that simultainiously controls both left and right channels?

Yes, two regular stereo 2-gang pots.

I ask because I'm wondering if I wired 2 decent stereo pots up to the main vol. if it would give me L/R balancing.

Hard to impossible to achieve the perfect channel balance this way. I strongly recommend finding a 4-gang pot that will somehow fit inside E1. If not, then use a comfortable output volume on E1 and adjust for lower output levels by software (OS).

A couple of these perhaps? https://www.hificollective.co.uk/potentiometers/tkd-2cp-601s-potentiometer.html

Feel free to read https://www.head-fi.org/threads/asu...-dac-cebit-2011.542563/page-229#post-13125460 as well. You need B10K for the middle pot. and A10K for the headphones pot. Impossible to find the originals, but at least you might try finding no-brand 4-gang pots. Just take care of shaft's diameter and overall outer dimensions. I think the orignals are 9mm shaft pots., but please measure prior to ordering...if you will find any available somewhere.

You might want to double check this: https://www.alibaba.com/product-detail/RK097G4L-09mm-quad-unit-rotary-potentiometer_62066284851.html.

Either way, I will start with the cleaning method first.

This should do for a while for sure, give it a try.

 

[r343]

Is it okay to lower balanced output from pot? Manual says its outputs 4v so i would assume its 2v at when pot is at 12 clock.

I have some problems with Violectric V200 running too much volume, i cant even reach 12 clock (HD800) with lowest gain on amp when Essence One output is at full position using xlr connections.

 

[raoultrifan]

Is it okay to lower balanced output from pot? Manual says its outputs 4v so i would assume its 2v at when pot is at 12 clock.

The potentiometer from the middle is linear, so yes...at around 12 o'clock you will be getting about 2V RMS on XLR output plugs and about 1V RMS on RCA.

However, best SNR will be achieved with volume to the max. on E1

I have some problems with Violectric V200 running too much volume, i cant even reach 12 clock (HD800) with lowest gain on amp when Essence One output is at full position using xlr connections.

I strongly recommend you to setup correctly the gain settings on your V200, based on https://www.hifisentralen.no/forume...tric-hodetelefonforsterkere-v200-e-manual.pdf. You should be fine with an overall gain of 0dB (unity gain), but feel free to experiment with a pre-gain of -6dB or even lower.

 

[mBTX]

Hmmm, weird. Both the DAC and the amp pots are of the B10k variety on my E1. Wonder if mine has been repaired??? Could this cause any issues in your opinion?

 

[raoultrifan]

Both the DAC and the amp pots are of the B10k variety on my E1.

This is normal, mine has same B10K, only MUSES has A10K on the headamp. B10K is linear pot., while A10K is logarithmic (normal for use inside amplifiers).

 

[mBTX]

Thanks for sharing your links and knowledge.

People like you are what make forums like this great.

 

[harrihart]

Hello. I have Essence One Mark 1 Muses Edition (genuine), and got DSD Upgrade Kit, used from Amazon many years ago. I expected Muses 02 OP Amps that came with it to be fakes, and never installed them, or the DSD upgrade part. I used it with Adam A8X studio monitors quite happily for many years. Now I got back to headphone listening, and this is the only desktop DAC/AMP I currently own. I have modded Sennheiser HD800 and many other lower end cans. I'm not too picky with gear, as I know the results will never be worth the increased cost, if I go much up from here, but I'm considering DAC/AMP/Pre-amp upgrades, like RME ADI-2 DAC FS. However, I'm pretty happy with the sound I get right now.

Now I actually think these OP Amps might be real, from the other threads. Everything else says they are real (even legs are very soft, and bend easily), but I got two different numbers, and the other one's paint is "stronger"/different color. Not sure if I heard any difference after switching them to the place of 49720s, first I got the impression that it had less bass, and was disappointed, but after that everything else sounded awesome. This might all be placebo. At least they work. You think these are real? I'm pretty sure the EEPROM part is genuine, and installed it too, but haven't updated firmware yet etc. Image https://ibb.co/VM8LcXK

As I have I/V stage (4) and LPF (2) already filled with Muses 01 OP Amps, I put the two extra Muses 02s to headphone buffer. Feels like waste to not use all 8 Muses OP Amps I now have, instead of the original 49720s. Is that stupid? Should I switch the Muses 01 LPF ones with Muses 02?

So, LPF with Muses 01 + headphone buffer Muses 02,
Or LPF with Muses 02 + headphone buffer Muses 01?

I don't really care about switching and trying and buying different OP Amps (tried that before, and it was fun with simpler amps, but still), as the differences are very hard to hear/remember. Also the soft legs will surely broke if I try that. But still asking.

I got the impression that switching XLR (that I use), headphone, or RCA buffer OP Amps will not give much benefits. Should I keep the XLR ones like they are, or is there some cheap upgrade available? I don't care about the best, expensive parts in this old device. Buying that DSD upgrade kit was stupid too, there is really no any benefits for me, Tidal user, for my already Muses Edition.

 

[raoultrifan]

They look real to me, hope I'm not mistaken. You could keep the default NE5532 in I/V, LME49720 in LPF and the LM4562 in buffers and sell the MUSES. This will save you some money without altering the sound in a wrong way (E1 will sound, with the default opamps, as the original studio mix).

RME ADI-2 DAC FS would be a real upgrade indeed.

 

[harrihart]

Would they ship DSD Upgrade Kit with such different looking OP Amps? All the x6 Muses inside my unit are identical, with same numbers.
It would be easy for someone to switch them to fakes, return and get free Muses's.

 

[raoultrifan]

Perhaps some more pictures might help here, with the two MUSES 02 opamps. Basically, if the pins are easier to bend than regular opamps and the big edges are rounded there's a good chance to be original. With better pictures, without flash and from different angles, we might inspect the top of the opamps even better.

 

[harrihart]

I think they are real. Sounds too good to not be.

I decided to be brave and try not to break the legs. It worked well.

First I put 49720s back to headphone output (so everything Muses Edition default). Not big difference, but I think it was slightly sharper and colder, with smaller soundstage. Someone might like this with their headphones. I didn't with my HD800. (my previous observation was totally wrong, I had long break between listens then).

Then I put Muses 02's to LPF, in place of Muses 01's. Like you suggested many times earlier, as one good option. BIG CHANGE in sound, much warmer, more analogue, tubelike, whatever. Some pleasant crackles and distortion. I'm pretty sure this classifies as less hifi, but I absolutely loved it with HD800. I have never had tube amp by the way, so don't believe everything I say. I dunno how much of this is placebo, as I knew Muses 02 was supposed to be warmer (and worse for most), but I'm 100% sure there is some/big change in sound.

Then I put Muses 01's in place of 49720's to headphone out, so everything in "chain" is Muses. Smaller change. I'm quite sure this improved soundstage/highs/details (restored them some, that the previous change maybe took away), adding even more raspiness to the sound, maybe even too much for some. Depending of songs it was sometimes on the border of being too much, but most of the time awesome. Best sound I have ever had from my HD800. All that warmth in mids and lows is still there, maybe even more. Other areas are just improved.

It also almost fixed HD800's annoying treble problem, with some songs. Together with the mod. Definitely better, good pair. But not perfect. Now I almost don't want RME or anything else more neutral, because this is hard to beat. For now.. (RME might have some EQ fixes, I'm not a fan of EQ at all, but at least previously, HD800 was not usable with some songs, so something has to be done. But now it's better.