[Elegiac]

I use LM4562NA's... supposed to be the same thing as LME49720.

 

[Kuze]

What do you think about the EQ200 or SA200 from Aliexpress?

Reviews: "Was not out played by either Sonic or Burson V6"
Aliexpress.us

 

[TheManko]

I saw questions about MUSES03, and also comments in general that bothered me, so I decided to post. I last posted in this thread some years ago, so I might be repeating things in this post. But it's how I feel at the moment, so any repeated points just mean they're still valid to me.

To set the stage a bit, what I want from my sound system is involuntary emotional responses. This is generally produced by a combination of dynamics, speed, resolution, tone and general feel. The kinds of emotional reactions I'm looking for depends on the music and material. For example, Burson V6 Vivid are good at producing the feel of energy and power of a live event. For sheer scale and energy, it's one of the best. For example, V6 Vivid is good at making generic "epic" music sound as epic as the composer intended. I'd recommend them for video games. But for vocal focused music, they're mediocre at best, and this is where MUSES comes in. They have their quirks and flaws, which clearly make them polarizing. But MUSES01 has maybe the most beautiful sound I've ever heard from a chip, whereas MUSES03 is in my mind clearly up there with OPA828 as the best chips currently available. If I put OPA2156 in my amplifier I can listen to almost anything and experience an emotional flatline. I get a clean and clear sound, but I can feel my enthusiasm for music draining away every second. But if I install MUSES03 I'm suddenly grabbed and amazed by the power and presence projected by vocalists.

All my evaluation is done over speakers, as I'm swapping op amps in the input stage of a Purifi amp. It's one made by Audiophonics Workshop. It allows you to bypass the input section entirely, so I'm able to use my Phonitor X to drive the ouput stage directly and hear how much detail is removed by initiating the input stage with its op amps. All the op amps remove some detail, with MUSES03, OPA828 and AD797BRZ removing the least. I have two discrete op amps, SS3602 and V6 Vivid. They're close runner ups for the chips, but mess up the sound in different ways that I don't enjoy, so they mostly collect dust these days. I'm looking forward to Burson's V7 to see if they can win my nr 1 spot. The reason I use the input stage at all is because it fixes problems with dynamics and phase. With no input stage active the treble becomes too leaned back and flattened. The sound in general becomes so mellow it puts me to sleep.

The reason MUSES costs so much is because of their novel design. They are all two chip designs, as compared to other integrated chips. MUSES01 achieves -150db crosstalk thanks to this two chip design, whereas MUSES03 being a single channel op amps uses the two chips to separate input and output stages. OPA1612 "only" achieves -130db channel separation. How much does this matter for the audible sound quality? Probably not much, but it shows the MUSES op amps were designed with a high standard in mind, even if it doesn't show in many measured parameters. In the case of MUSES03 the two chip design creates a remarkably powerful output stage at 250mA, which makes all the competitors look weak as they usually only achieve 30mA-100mA.

In general, op amps eat detail, meaning that each one degrades the sound quality slightly. Newer op amps generally preserve detail better than old ones (like OPA828 vs AD797BRZ), and single op amps tend to preserve more detail than duals (like AD827SQ vs AD847SQ). Whether this is a problem or not depends on the price level of gear we're talking about, and I've recently found it also depends on the signal chain as a whole. I've read on DIYAudio forums that a reason dual op amps perform worse is because the crosstalk between channels isn't just electric, but also thermal. Sometimes the loss of using a dual instead of single op amp doesn't matter too much. I've found it makes a big difference if you have 3-6 op amps in a row, like say I/V, LPF and Buffer, or even an op amp based DC Servo in the signal chain. That's where you can gain an amazing amount of extra resolution and sound stage width by swapping duals to singles on adapters, or getting a bunch of discrete op amps. But what I've found is that sometimes the loss of detail can just be in the single % range, so having a dual is no big loss. It all depends on the signal chain as a whole whether it matters.

The question came up recently, why do we swap op amps at all? Why swap op amps when we can simply buy a properly designed device instead? Because that costs money! If we can look at higher end devices for inspiration, modify our own to copy aspects of their design, then doesn't that mean we got 90% of their sound for a fraction of the cost? Probably not, but it feels good when it sounds like we did! Esoteric D1X uses 16 MUSES03 op amps in the filter section. From the Esoteric website: "MUSES03 which was produced through many years of joint development with New Japan Radio Co., Ltd." How much of that $50,000 sound am I getting by blindly putting them in the input stage of a €1100 Class D amp? Probably not a lot. But it sounds good to me, so I'm happy.

Another example, I upgraded my Purifi amplifier with WBT Next Gen Silver speaker terminals, Neotech solid core UP-OCC wiring to the speaker terminals, and also Neotech solid core silver wiring from the XLR inputs to the input board. These are the kinds of upgrades you see in high end Purifi amp builds, but I could do this on my own for just the cost of parts and 4 hours of labor on a weekend. This made a big difference to the sound, so I'm very happy with the result. The chassi for the amplifier is also a bit cheap and had a ringing noise, until I lined it with Dynamat Xtreme. Now it's completely inert, possibly improving the sound like a higher end build would. Then I also put Pangea Sorbothane feet on it. As with op amps, I'm just bolting more expensive parts to this amp in the hope it'll make it sound better. Every tweak seems to work, even if some only change the sound in a miniscule way. The cabling and op amps made by far the biggest difference.

Anyway, back to MUSES03 vs other op amps. MUSES03 have a tone that's feels more or less neutral and correct, with a touch darker tone compared to OPA828 or AD797BRZ. It's only slight, but the difference is there. Their strength is the midrange, but I enjoy their character as a whole. Compared to discrete op amps, MUSES03 can sound startingly dynamic. I said V6 Vivid have a powerful sound, but they're somehow also sluggish and slow compared to chip amps. They have the power, but not the speed. MUSES03 can be much more dynamically varied and impactful than V6 Vivid in a lot of music. MUSES01 and MUSES02 have a much more colored sound than MUSES03, with MUSES01 sounding like everything has been pitched up, and MUSES02 sounding dark and boomy. OPA828 (and other modern OPA models) has a more neutral character, but in a more dull sense. If all you listen to is real life recordings and sound effects, then OPA828 is amazing. With something like the engine start-up sounds in Gran Turismo 7 it can almost like you're in the same room as the car. But for music, they're only satisfying with certain genres. With vocals they're an emotional flatline for me, but with progressive metal or electronica they can be excellent. They have a superb sense of speed and focused impact, so it can feel like musicians are playing faster because each note is being reproduced with more precision and "blackness between notes", or however you describe the effect. Depending on how you listen, what you listen to, they can be the holy grail. I vastly prefer them over OPA2156 and OPA1611, as they are too similar but worse to my ears. I haven't tried OPA1656 unfortunately, so I can't tell how it compares against it. But I've compared OPA828 against OPA627AU, BP and SM versions, and OPA828 blows every version of OPA627 out of the water. Every time I listen to OPA828 I admire them, but I always end up going back to MUSES03. Because in the end they give the most satisfying listening experience across the widest range of material. They're not as epic as V6 Vivid, or as precise as OPA828, but they're close enough. They have their own strengths that makes me come back to their style. But if I get tired of them, I can just spend 5 minutes swapping to a different op amp. I'm probably not hearing anywhere close to the full potential of any of these op amps, as the circuit wasn't strictly designed around them. But I'm still enjoying myself more with these than the mediocre stock op amps, so I'm happy playing amateur designer.

 

[Elegiac]

Aha. Well. If MUSES03 is as clear-sounding as MUSES8820, then it'll work for me.
But for the meantime, I'll be using a pair of 8820 in the balanced output of my DAC.

My MUSES03 are shipping from Japan, and it's... a bad time. The Earthquake hit the day after my purchase.

 

[TheManko]

I've unfortunately never heard the MUSES8820 or MUSES8832, so I can't tell you what kind of upgrade you can expect going to MUSES03. It should be big, given that the cheaper MUSES models use a single chip instead of two chips like MUSES01, 02, 03 and 05. Like many others I started my op amp rolling on the Xonar Essence back in 2008. First buying the metal can LME49720, and then jumping straight on MUSES01 when they came out.

 

[Elegiac]

8820 is apparently similar to 02, both being bipolar.

 

[TheManko]

I went through a round of op amp testing since my last post. I retested MUSES01, MUSES03, OPA828, and AD797BRZ.

MUSES01 in this particular setup has a clean and smooth sound with a beautiful tone. It's not a dry or grainy type of sound, but one that's "wet". This glossier, smoother or wetter character is one of the clearest differences between discrete op amps and integrated chips. Discretes are usually drier and grainier, kind of like listening to a tape. This difference in texture makes a big difference in the perceived realism of the sound for me. A more wet sound usually gives more realism, as long as it's coupled with enough sharpness, dynamics and resolution. The more dry sound of say V6 Vivid gives a more old school analog feel. But that analog feel comes with flaws which are too audible so it never sounds truly realistic, as the texture of the sound is wrong, although in a pleasant manner. The reason I bring this up with MUSES01 is that it's probably the most wet sounding of all chips, which is probably aided by its tonal character that seems to shift everything to be a tad brighter. What keeps MUSES01 from sounding truly realistic are its other flaws. It's less detailed than all the other op amps tested, giving all sounds a more soft edge, and it's also the least dynamic. Compared to MUSES03 it simply comes across as inferior. If MUSES03 didn't exist, then I'd consider it a lovely alternative to the other op amps. But I can't make myself use MUSES01 because I also have MUSES03. Still, a very enjoyable sound!

MUSES03 is like if you more than doubled the detail level of MUSES01 and tripled the dynamic range. Music that sounded big but also a bit two dimensional with MUSES01 suddenly sound like 3d with MUSES03. The bass punch is much more powerful, which I think is why I've seen some describe MUSES03 as a cross between MUSES01 and MUSES02. MUSES02 has a more closed in and punchy sound, and that power is there with MUSES03, but at a higher level of quality. It's also a bit warm and maybe a bit tad too smooth for its own good. It’s not overly polite, as it has plenty of attack and presence. Can’t put my finger on what it is exactly that I’m perceiving as a flaw, as I believe it might simply be exposing weaknesses elsewhere in my system, whether it’s room acoustics, or something else. It all depends on what I'm listening to, as it’s sometimes clearly the best.

OPA828 is just as precise and detailed as I remembered. It gives maybe the most linear, firm and clean bass impact, and it holds back just enough to not overdo it. You hear everything, it's all superbly balanced, and there's nothing wrong, at first. It's almost perfect, if it wasn't for a critical flaw. I think it sounds like listening to the audio equivalent of digital noise reduction. It's too smoothed over and cleaned up to where it has no sense of realism at all. You can always tell you're listening to digital sound, because there's something fake about the tonal character to everything. The treble is the worst offender, as cymbals have none of the bite that they should have. That's all been smoothed out. This is like the opposite end of the weakness of discrete op amps. For pure musical enjoyment, I'd probably prefer something highly flawed but with more charm over this. It's a bit like how people describe professional monitor speakers. Perfect sound, but unsuitable for actually enjoying music. Still, a great sound overall. I'd love it if people actually built something using this chip. I don't know if anyone has! Everyone just uses OPA1612 or OPA1656 from what I've seen. I'd love it if someone made a surround processor with OPA828, as the clarity and bass performance would make it very impressive.

I prefer AD797BRZ over OPA828. They're an older part from the early 90s, that on paper are about 1/8th as fast and resolving. I usually don't like older op amps, as they usually sound like obsolete with no redeeming charm. The exception being AD797BRZ, as it's the only chip I've heard that sounds like a discrete op amp. They have a drier, slightly grainier and bigger sound, just like how discrete op amps sound. Tonally it's very similar to the Sparkos SS3602. But unlike the discrete op amps AD797BRZ has a more consistent character across the whole frequency band, with consistent speed and resolving capability. With SS3602 the treble is too leaned back and almost hazy, the bass is also too vague and makes bassists hard to hear, but with generally good midrange performance. AD797BRZ has none of these issues, but also retains the positives of SS3602 of having a general tone and feel that's "just right", somehow. It's not smoothed over, but raw and direct. Cymbals have a level of attack and bite that gives a feeling of realism and being in the room of the recording. AD797BRZ were made for submarine sonar systems, whereas OPA828 was made for ultrasound machines. I have no idea how much of their audio performance was intentional or just a byproduct of their actual intended use case. With a fresh set of comparisons, I AD797BRZ and MUSES03 are my top two.

For now, AD797BRZ will be staying, because I can't be bothered to swap again today. Both are excellent in their own ways. MUSES03 is more punchy, dynamic and clean. It gives a higher end feel to the sound, whereas AD797BRZ is more linear and drier, with possibly too much treble energy. I think both max out the resolution capability of my system, and just balances the system out in different ways, giving them a different flavor. There’s room for other op amps to come out and improve on what these models are doing, hence why Burson V7 might turn out to be a big deal. If it’s more consistent and precise than SS3602 and V6 Vivid, but also bigger and more dynamic than all the integrated chips, then it’ll become the default recommendation for anyone wanting the best upgrade path. We’ll see! I’ll be getting them when they become available. But until then, I’ll be using AD797BRZ and MUSES03.

EDIT: It took me 5 days, but I finally swapped back to MUSES03. This gave me some perspective on the performance of AD797BRZ vs MUSES03 and also MUSES01. Like MUSES01, AD797BRZ lacks dynamics compared to MUSES03. They sound lovely, most of the time. But I noticed that songs I usually enjoy were boring and causing me to get restless. What finally made me realize what was happening was a drum solo in a Chihiro Yamanaka song. I’ve heard the song dozens of times with MUSES03, so I knew how it should sound. AD797BRZ flattened out the dynamic range of the song making the drum solo lose most of its expressive power. Swapping back to MUSES03 was like removing several layers of digital noise from the signal. The sound of MUSES03 is simply far purer and more transparent, meaning it for example makes all cymbals sound different. In a lower end op amp, like AD797BRZ, cymbals tend to all sound the same, like every album across history was recorded in the same studio. This means my opinion of AD797BRZ has dropped a few notches, putting it below MUSES01 as a nice but inferior alternative. I still like both. But with fresh tests I think MUSES01 is better, and MUSES03 is clearly superior to both.

 

[jolivhires]

I've decided for JRC5532DD and OracleII 02 for my Fosi V3 after checking this forum, YT compares and reviews and see which ones are good for my ears. Meanwhile, as I do listen to my cassette tapes (many of them recorded on different recorders with different sound colour and aging effect), I've decided to get V3's mate, the P1 pre amp which has tone control and also comes with the stock NE5532's opa's. Once everything arrives, I'm considering the following scenario: replace on the P1 with the JRC5532dd and replace on the V3 with the Oracle's. I can play around doing the other way and test, what you guys think would be the best scenario, even considering retaining the NE5532's on the P1 pre and just see which ones fit best on the V3.

 

[evonimos]

Muses series of opamps are of great quality and pretty easy to implement.
I also enjoy the fact that they are still offered in the classic DIP8 package.

Used Muses01 in a DIY phono stage (among other things) with satysfying results.
Detailed sound without getting too sterile. Great imaging too.

Also used Muses8820 in the same setup and sounded very nice.
It had a more 'romantic' sound than the latter, with a smoother top-end, a bit warmer overall.
Great for vinyl i guess. Reminded me of an improved version of their very popular NJM5532.

By the way, the JRC version of the ubiquitous NE5532 is smoother, and a bit more 'analogue' that the Texas Instruments version which is comparatively leaner and a bit more textured.

Wish folks at JRC would also release a metal-can package of their excellent Muses opamps.
I've found that metal-can versions sound a bit more lively and controlled than their plastic package equivalents.
Maybe has to do with slightly better heat dissipation.

 

[jolivhires]

I've decided for JRC5532DD and OracleII 02 for my Fosi V3 after checking this forum, YT compares and reviews and see which ones are good for my ears. Meanwhile, as I do listen to my cassette tapes (many of them recorded on different recorders with different sound colour and aging effect), I've decided to get V3's mate, the P1 pre amp which has tone control and also comes with the stock NE5532's opa's. Once everything arrives, I'm considering the following scenario: replace on the P1 with the JRC5532dd and replace on the V3 with the Oracle's. I can play around doing the other way and test, what you guys think would be the best scenario, even considering retaining the NE5532's on the P1 pre and just see which ones fit best on the V3.

Replaced the stock NE5532 by the OracleII 02 and did some hearing for a few hours. Overall more pleasantly bass and channel separation that's my feeling. Saw a rumour somewhere (but can't locate the video ) that it's based on OPA1612, well if it's the case, that one is a well considered opamp with very good reviews. Anyone knows more about this?

 

[Elegiac]

Replaced the stock NE5532 by the OracleII 02 and did some hearing for a few hours. Overall more pleasantly bass and channel separation that's my feeling. Saw a rumour somewhere (but can't locate the video ) that it's based on OPA1612, well if it's the case, that one is a well considered opamp with very good reviews. Anyone knows more about this?

https://www.head-fi.org/threads/chinese-opamps.967010/

 

[Ben86]

Could anyone reccomend an inexpensive headphone amplifier which would benefit from different dual OP-AMP rolling to increase sound quality? I have a pair of Burson V6, V5I-D, muses8820...

 

[Promee]

Hi op amp thread!

I am usually a tube person in most of my amps. I’m relatively new to being serious about headphones, and I just picked up my first serious solid state amp - the Violectric V222. As a lover of tubes, I’m super excited about the possibilities offered by op amps. I ordered 3 of the Sparkos SS3602 for my V222, which I believe will be suitable replacements for the TI op amps that are presently in the amp. I have been trying to find out some more information about op amps generally, but there is so much out there that seems ill-informed / difficult to trust. I’m curious if you guys have any thoughts about which op amps in an amp (there are 3 I can identify in the V222) make a difference to swap, or if they can all offer a benefit? Second, these seem to have meaningfully different gain ratings than the op amps that they are replacing, and it started me wondering if this will change the overall gain of the amplifier or any other characteristics like overall power output, heat, efficiency, power draw, etc. I am definitely no electrical engineer, but I am curious about all of this stuff, and any insights or resources for beginning op amp rollers to start to understand some of the technical details would be greatly appreciated!

 

[TheRealDz]

Hi op amp thread!

I am usually a tube person in most of my amps. I’m relatively new to being serious about headphones, and I just picked up my first serious solid state amp - the Violectric V222. As a lover of tubes, I’m super excited about the possibilities offered by op amps. I ordered 3 of the Sparkos SS3602 for my V222, which I believe will be suitable replacements for the TI op amps that are presently in the amp. I have been trying to find out some more information about op amps generally, but there is so much out there that seems ill-informed / difficult to trust. I’m curious if you guys have any thoughts about which op amps in an amp (there are 3 I can identify in the V222) make a difference to swap, or if they can all offer a benefit? Second, these seem to have meaningfully different gain ratings than the op amps that they are replacing, and it started me wondering if this will change the overall gain of the amplifier or any other characteristics like overall power output, heat, efficiency, power draw, etc. I am definitely no electrical engineer, but I am curious about all of this stuff, and any insights or resources for beginning op amp rollers to start to understand some of the technical details would be greatly appreciated!

I will get you a proper answer in the next day or so. I replaced 2 of the opamps on my V222 with Burson Vivid 6s, to great effect.

 

[Promee]

I will get you a proper answer in the next day or so. I replaced 2 of the opamps on my V222 with Burson Vivid 6s, to great effect.

Thanks a bunch! I look forward to finding out! I might have to try some of those Bursons as well…