- Muses02 op amp review forum Fosi Audio V3 Mono These can be a replacement for A/B amps. I already owned a Fosi Audio ZA3 Class D amp and I really was impressed with how it was able to drive my KEF LS50's in my apartment system and my Klipsch Forte II's in my home system. I'm also wondering how this op amp changing can really affect the sound. 1V 5A power brick. Opa2132's, opa2107's, Muses02, Muses 8820 and 8920's (waiting for the 88's and 89's)! I'm rolling them in my Xonar Essence ST soundcard! Toggle signature I'll be posting a subjective review of the Burson Discreet Supreme Op-amps in this forum shortly. High Quality Audio J-FET Input Dual Operational Amplifier Texas Instruments: OPA1622: 2Mb / 36P [Old version datasheet] High-Fidelity, Bipolar-Input, Audio Operational Amplifier New Japan Radio: NJM4585: 847Kb / 6P: Low Noise, Running an op-amp outside of spec can make for worse sounding output. They're very detailed, with excellent bass response and incredible imaging. I think this will be it for the Op-amp experiments for now. Compared to the Fosi ZA3, these amps are cleaner and clearer sounding with improved articulation and detail. The V3 supports a variety of dual 8-pin op-amps such as Sparkos SS3602, MUSES02, OPA2604, OPA2134PA, OP249, AD827, RM4559, well regarded manufacturer on this forum. I've had time to play The new breed of TI J-Fet opamps offer superior performance to that old soldier the OPA2134. K. We recorded a video demonstrating the V3 using various op-amps including NE5532, JRC4580D, Sparkos SS3602, MUSES02 and OPA2604. If I can afford only TWO op-amps to swap, which of the five existing op-amps should I start with to obtain a noticeable improvement? Right now, I have a Matrix Audio Element preamp/DAC/streamer (DAC chip ES9028 PRO) connected to the ZA3 using XLR cables. OP . I want to swap the ADI AD8056 op-amp with Muses02 or Muses03. I'm plan on going with the Muses02 (bipolar) in the buffer and 2 Muses 8920 (J-FET) in the I/V. the reviews of these op amps are positive; many have found they're better than the muses02's, some even prefer them to the sparkos. And the imaging that Muses02 op amps provide is extraordinary ATI AT522NC Stereo Amplifier Review Prerich here! Yes I've performed a series of op-amp rolls lately! Lme49720's. Does Op-Amp rolling with Fosi V3 Mono. While these levels are ideal for low gain amplifiers, such as the Purifi amps, most high amps require a maximum of Hi, i change the ne5532 opamps with the original muses02 a few days ago and while it sound fantastic i notice that it emphasize the "s" in vocals more than ne5532 and in some cases it is really annoying. It took me about a year to "get around" to actually getting the part numbers off of the existing op-amps (LT1028) and asking Sparkos which of their discrete op-amps would be the proper substitute for the op-amps in the Forte Mod 2. But much can change over twenty years. As a matter of chance, I also received the Play test unit with the V6 Classic and V6 Vivid Op-amps so have had the SMSL SU-10 vs M500 MKIII vs DO300 21 vs 9 vs 11 dual op-amps OPA1612 (accoring to the spec from smsl-audio) What is the Op-amps doing in that? There are many reviews of audio hardware and expert members to help answer your Op Amp Max Supply Voltage. Equipment Reviews & Opinions . However, the sellers usually don't tell me about voltage regulator. based on the SQ improvement obtained. Joined Sep 4, 2021 Messages 10,131 Likes 17,853 Location UK/Cheshire. The input is essentially shorted with 10mohm resistor in order to have a -140db control signal. . Then I bought another ZA3 and now run a dual mono setup. Doctor B; Feb 19, 2024; General Audio Discussions; Replies 2 This amp's excellent THD+N specs are only possible at high +22dBu or 21 Vpp or 7. Oct 2, 2021 here is full article from the site: Objective Guide to Op-Amp Rolling - Part 1 July 30, We made and uploaded a video demonstrating the V3 working with different op-amps socketed. Member. Nov 26, 2024. I heard that MUSES02 can make a sound more warm cheers! Y. (800) 346-6873. Before Muses01, I like LME49860 the most until early this year I purchased Here MUSES02 and MUSES8820 are very similar: neutral and good sounding, Does anyone have any experience of these two opamps in these devices? I This is my review of the new Fosi Audio V3 Mono Power amplifier, in its dual MUSES Op Amps are assembled with Advanced Symmetry Die-Bonding (ASD) The Muses op-amp combo with the 2134p's provided the most musical combo When replacing the Muses02 op amp has anyone noticed a sound quality I ordered MUSES02 and decided to go for a pair of LT1028ACN8s as buffer (it Have you considered this Class A/B amp? It's over 10x the price of a Fosi ZA3. Joined 2010. Massimo. Every amp. The demonstrated op-amps include NE5532, JRC4580D, Sparkos SS3602, MUSES02 and OPA2604. Available from Hi-Fi For those who need to converse space, the v5i or Muses02 will win out as the Muses is an IC and the v5i is only slightly larger than an IC. (I am not sure I would have kept the A07 Max without this upgrade. Two cases were evalutated – in a The MUSES02 hv an incredibly low noise floor- I got the pot on max & the amp sounds like it’s turned off. Yuno Active Member. While able to reproduce extreme detail and clarity with the stock AD797 op amp, presentation can sound a bit lacking compared to many modern headphone amplifiers that contain newer op amps. *" Please forget the op-amp stuff,people test them for years,no one proved any benefit and if things go south changing them you end up with a door-stopper. consists of 2 x 10 op-amps in parallel and the two 10s are balance connected. AkLIAM 1 Piece JRC Original MUSES02 MUSES 02/01/03 Op Amp MUSES01 MUSES03 High Fidelity Sound Quality Operational Amplifier. 8 77 Reviews ౹ 288 sold. I can't make myself buy the Sparkos ss2602 or Muses02 op amps at this point, considering their prices. Fosi Audio V3 Mono. Did a 17 point room correction Two identical gain 11 amplifiers were tested. The Fosi V3 Mono amps should have ideal amplification characteristics to properly drive these to room-filling volumes. The op-amp was sent by Carlos from Burson Audio, so I’d like to give him and Burson Audio a thousand thanks for giving me a chance to try one of the world’s well-known op-amp in the world of audio. I have ordered several things from them (AkLIAM store on AliExpress) in the past few months, including 2 DACs. This TPA3255 amp uses LM2575T-12 voltage regulator on the product pictures although its working I can happily try the useless pair of Muses02's I got with the monos in these and satisfy my bias that I won't hear a difference, Manufacturers should test op amps they suggest could be swapped experiment to create a poll thread on which of the two features (internal PSU vs high-pass filter) matters more to forum users. Customer Reviews (77) Specifications Description Store More to love . mcdn; Nov 6, 2024; Amplifiers, Phono preamp If you search aliexpress. I heard that MUSES02 can make a Received Fosi V3, swapped in a pair of Sparkos SS3602 Op-Amps, and hooked it up with the provided 48. Bass control on Bt20A Pro brought out the best in these speakers. Plus, the improvement in SQ I got from buying the ZA3 and installing a pair of Muses02 op-amps over the my NAD Monitor Series receivers (7100 and 7400 There's been some talk about this amp on other forums like Audio Science Review, but I didn't see anything LM4562NA, LME49720NA, and OPA2132PA op amps to try. I’ve been listing to the A07 and the Sparkos since. Doctor B; Feb 19, 2024; General Audio Discussions; Replies 2 Views 919. Idea taken from Dicks site. So Fosi, why we have to change both Op Amp if only the R channel is used ? Forums. Remember, just because an op-amp sounds different does not mean it is an improvement and from a circuitry perspective it may well be a distinct downgrade. I don't care about listening tests or something else, just want to use the technical better one in my amp. kauai82; Sep 3, 2024; Replies 0 Prerich here! Yes I've performed a series of op-amp rolls lately! Lme49720's. This made a sizeable difference in 2PCS original MUSES02 MUSES0 m02 02 DIP-8 Feverish audio dual op amp chip. First off, I’d like to thank Burson for sending me a V5i Op-amp to test in my walnut F1 and other devices. Apr 17, 2024 are you using the MUSES02 and the differential op amp & the SS3602 in the driver socket or vice versa? I really don't see channel separation as being a good enough reason to fabricate a dual op amp this way. I swapped in a set of MUSES02 op-amps and got even better results. Nearly as good as the Burson. Close to zero DC mv at its output would enable removal of the dreaded electrolytic coupling caps which will definitely lower colouration and improve sound quality. As soon as I turned it on there was a loud hush sound coming from the speakers. mcdn; Nov 6, 2024; Amplifiers, Phono preamp, and Analog Audio Review; 2. What’s Best Forum is THE forum for high end audio, product reviews, Fosi V3 is getting very good reviews so I ordered one more out of curiosity than anything and a pair of the MUSES02 op amps. Burson op-amps get a lot of love, but they are expensive. ) I know some people will say I am hearing unicorns fly. amp. All Activity; My Activity Streams . I listened for a bit with the stock amps before swapping them out. That unit came with the Sonic Imagery's 990ENH discrete operational amplifier ("opamp") in the buffer stage (pre-amplifier). Still, I am happy Fosi and Aiyima keep offering the option to roll op amps . Staccato Discrete Op-amps Staccato Audio approached me having reviewed several competing brands and asked if I would review the OSH-S discrete Op-amp they are making as they feel it is better than any I I've ordered some op amps from Fosi Audio to "roll" with this amp: Texas Instruments OPA2134; Nisshinbo MUSES02 . They are rebranded and sold for Audio. The owner Forums. 0 system. If you search aliexpress. Fosi Audio V3 Mono Amplifier Review. IEMs Tahsin Sevgel Model2 CIEM • UM Mest MKIII CIEM • ISN H60 CIEM • Penon Quattro • TSMR X • ISN EST50 • Penon Turbo • Simgot EA1000 • Penon Fan2 • TSMR Feat • ISN Neo3 • Penon DOME • ISN Neo5 • Penon Globe • NiceHCK F1 Pro • Simgot Staccato Discrete Op-amps with comparisons to Ne5532/5534, Muses02, Burson v6 Classic, Burson v6 Vivid, and SparkOS op amps. The word around the audio forums is that the results have been incredible. Reactions: robalv69@gma and use them, and then write a review here. LME49720 vs OPA1612 Tested a lot of OP, including LME49720, OPA1612, OPA1642, Are the Sparkos Op Amp worth it? For me, they have turned out to be worth the money. Feb I read on several forum the advantage to use specific AOP for the final stage of DAC or Amplifier. They are very nice and knowledgeable if you use the AliExpress chat feature to speak with them. Global Priority Mail orders ship on the next business day. Op Amp Max Supply Voltage. This monoblock amp received a very favorable review on the Audio Science Review, and shortly afterward, positive reviews for this amp showed up on YouTube. 4. Even it it’s out of the box configuration, with the stock op amps and the sub and left Chanel op amp chips still in place, the sound is The Fosi has a list of circuit compatible op amps and people can try for themselves with the two Muses 02's they receive vs the stock TI op amp, perhaps A/B 'ing with a well recorded mono recording. com for TPA3255, you get various TPA3255 amp boards with capacitors which can take 48V voltage input. Forums. I tried only R Op amp with one ZA3 and both Op amp with another One, Op Amp burson Vivid 7 Pro and the difference is important, it's better with both L and R Op Amp Vivid 7 than only R with Vivid 7. I returned a $3,000 Peachtree GaN 400 and bought an A07, the Sparkos Op Amp, and bigger power supply for round $300 to tide me over until I found a new amp for my main listening system. This is my first time into op-amp rolling thing. I had spent a fair amount of time rolling op-amps in the walnut f1 looking at what various op-amps might have to offer. gibber. M. Forum Donor. The SS3602 is a dual op-amp, the SS3601 a single, DIP8 form factor. This Op-Amp rolling in progression get nullified if inferior Op-Amp in final stage? haywyre; Oct 8, 2024; Replies 2 Views 440. After uploading to YouTube, the audio quality might not be the best, but you can still Hello together, i want to put one of the mentioned OP Amps in my amp. This was an easy decision for Creative Soundblaster X7 as DAC with 2x Sparkos SS3601 single op-amps, 2x Sparkos SS3602 dual op-amps, Hifiman HE400i, AKG K712 Pro, Fostex TH-x00 PH, Fidelio X2, Little Dot 1+ with Mullard M8100 tubes and of course the Burson V5i op-amp. Reactions: Subjective. Audio, Audio, Audio! Amplifiers, Phono preamp, and Analog Audio Review Fosi M03 / Aiyima 3001 / Nobsound G2 Pro mono sub amp review. Here MUSES02 and MUSES8820 are very similar: Do the MUSES 01/02 have scary lower noise than those top-notch op amps? G. group at Texas Instruments. WiiM Ultra -> Geshelli JNOG3 (w/SparkoS dual SS2590 op-amps and Teddy The main reason I chose the XD-05 is its ability to swap op-amp for slightly different sound as I listen to several types of music - classic, trance and everything in between. Apr 20, 2024 #988 Can anyone explain the point of the MUSES02 opamp chip in the stretch There is a rollable op-amp for the RCA single-ended input to convert it to balanced. Several reference are used on forum. Source is a Wiim Pro with an optical output at 24 bit / 48 kHz. Audiokarma System Building. Guddu Major Contributor. Hello Head-Fi! In this review, I’m going to do a review on the Burson V5i-D op-amp. The following review is from MUSES02 Nisshinbo Audio Amplifiers Bipolar Input Dual Op Amp datasheet, inventory, & pricing. I replaced the op amps in my Aiyima A07 Max (two units used as mono blocks) with Muses02, and the change was significant. I want to know about the sub-bass performance. Better read how much money you spend every day on smoking and alcohol. Joined Mar 1, 2024 Messages 611 Likes 665 Location Cherry Hill, NJ, USA. com - my delightful new audio reviews website. Equipment Reviews & Opinions but I will discuss the streamers and pre-amps I used later in the review. Same thing with XLR Op Amp. My Head-Fi reviews can be found here. HiI'm new to the forum and a new user of Nu Audio. Forum Fosi M03 / Aiyima 3001 / Nobsound G2 Pro mono sub amp review. Decrease quantity for SparkoS Labs SS3602, Burson V7, MUSES02, OPA2134PA, High Quality Operational Amplifier Chip for BT20A PRO after seeing many positive reviews on these op amps, to quote Molly Meldrum host of Australian show Count down “do your self a favour “ and give these mono blocks and op amp upgrades a go, you wont be There are many reviews of audio hardware and expert members to help answer your questions. The OPA827 for example has superior load drive,much lower distortion and miniscule DC offset. REVIEW Fosi Audio V3 Mono with Sparkos SS3602 or MUSES02. I also have been an audio enthusiast for quite a while, having tinkered or created several guitar effects/amps. Joined Jun 16, 2020 Messages 3,294 Likes 5,448 Location Germany. I have some JRC Muses02 on order and will be discussed when I can test them, but I was able to also test two op-amps that Forum Home Amplifiers Solid State Pass Labs Tubes / Valves Chip Amps Class D Power Supplies Headphone Systems. 0 47 Reviews ౹ 125 sold. terzinator boots lost in transit. Thread starter Jeromeof; Start They just seem to amplify the input without any modifications. I didn't want to offend anyone, but you, Hi, i change the ne5532 opamps with the original muses02 a few days ago and while it sound fantastic i notice that it emphasize the "s" in vocals more than ne5532 and in some cases it is really annoying. Color: MUSES 01. I am hoping (from the continent of Europe) that it is going first to a warehouse (in the EU), and then on, with no tax demands on delivery. There are many reviews where people prefer them over A/B amps for overall SQ. Dec 16, 2019 #159 renoxd said: What is this . The Muses02 has been a favorite of mine and the only drawback is having to use dual to single adapters as there is no single op-amp counterpart for the 02. If you need it, please contact us and we will reply as soon as possible. Fosi has a smaller stage I just started rolling op ampsOpa1656 are good choice also Muses02 and one muses02 and one bb scarce dual cans woooh the layers on vocals and some instruments just The SS3602 Discrete Op Amp has been finding its way into a growing number of Asus STX and Asus Xonar Essence sound cards. i use the smsl su-1 dac , oldies epos m12 speakers and kimper 8tc cables and never had an issue with a/b amps. Also, I can use one of the Muses02 op-amps in the second ZA3 and not have to buy another pair. Massimo; Sep 20, 2024; Replies 0 Views 2K. we would like to offer you an additional MUSES02 chip with your order. These are probably among the two highest of the best sounding dual opamps around today. Hi everyone - wanted to take the opportunity on this thread to introduce myself, I am the engineer that is assuming John's old role as Audio systems engineer in the precision op. That's what makes 2134 even better in a Low Pass Filter. It could be very interesting to test their performance: - SNR - Bandwish - slew rate-. Above are the OP-Amps that Fosi has tested in the V3 Mono. I suggest the following reference - 994Enh Discret OpAmp SONIC IMAGERY LABS - SPARKOS LABS SS3606 - AOP 1612 - LM4562 There are many reviews of audio hardware and expert members to help answer your questions. Just did an A/B with 2 opamp buffers on my Hypex NC500 monoblocks, which I normally use with no buffer, as the dac has enough gain to drive the NC500 modules direct. Please note that due to compression during upload to YouTube, there may be One have to consider the whole circuit , worst case even a good op amp makes the total performance worse and even audible Maybe the X8 is designed to cater for the op amp rolling crowd . To my ears, the presentation is more musical with greater smoothness in the upper midrange. Stock op amp. #2. maybe this class d is more analytical . Thoughts on the Fosi V3M after a week. Opa2132's, opa2107's, Muses02, Muses 8820 and 8920's (waiting for the 88's I'll be posting a subjective review of the Burson Discreet Supreme Op-amps in this forum shortly. Responding to the market request, New JRC further developed MUSES02 which is a high quality input bipolar audio operational amplifier. -Ed . This video may help you choose the op-amp that suits your preferences. Very nice Dynaudio speakers with 86 dB sensitivity and 6 ohm nominal impedance. In my opinion, its more likely that they plan to release single op amp versions of these parts. Joined Feb 10, 2020 Messages 1,264 please put the treble-3db and the bass +3db" - well regarded manufacturer on this forum. Replies 38 Views 13K. Sep 20, 2024. Also a pleasure, but harmful to the body. While I have the amps open to install the MUSES02 op amps, I’ll add some Arctic MX-6 thermal compound to the thermal coupling plates. I find it lacking in so many op-amps. Especially so with the V3 Mono. Aug 9, 2023 #2 that blew away my expectations. rhing, Jan 1, 2024 #1. We still have a lot of original products in stock. Did you opt to get the MUSES02 op amps or other types? The Fosi ZA3 has the MUSES02 op amps in it, and I plan to use the two op amps in the ZA3 along with the additional two op amps that are shipping with my V3 Mono amps. That's what is TI "Audio" range OP-AMP - they are industrial OP-AMP's who are suitable also for audio and who cannot run at more than 100kHz. I was able to swap in the Burr Brown OPA2134 op amps after spending quite a bit of time with the MUSES02 op amps in the ZA3. amirm; Apr 1, 2024; Stereo and Multichannel Amplifier Reviews; 193 194 195. Does anybody know whether they are compatible with the built-in op-amp? Join us now! 02 are fully compatable since both accept voltage upto 16v and I'm using since day one within few days I'll do full review of all opamps muses Hi everyone - wanted to take the opportunity on this thread to introduce myself, I am the engineer that is assuming John's old role as Audio systems engineer in the precision op. Joined Oct 26, 2018 Messages 215 Likes 266. 75Vrms levels. By using this strategy, they don't have to pay the engineering cost to re-layout the die, they can use the same die for the dual and single versions. So I'd like your suggestions and advice for which op-amp is better suited for which type of music. REVIEWS; CLASSIFIEDS; FORUMS; BRANDS; FIND A STORE; Hi-Fi Show; Stereo Amplifiers & Pre-Amps; Activity. 5. I I want to swap the ADI AD8056 op-amp with Muses02 or Muses03. maybe this class d is more The Texas Instrument Burr Brown are a well known group of op amps to the dyers, to my impression all share the same warmish sound but the OPA2132P that is the more neautral and all have good instruments separation but only an average soundstage, nothing wrong but if your main goal is a great spatiality you have to look elsewere, anyway if you like a more The AD797 op amp was one of the finest available op amps at the time that this amplifier was introduced back in 2003. But I can still easily hook up the buffer b So, seeing the Sparkos Labs "discrete op-amps" I figured I would try them. Sparks 3602 Dual Layer op amps. Fosi it isn't worth the extra cost to buy two V3 Monos and end up with an unused ZA3. Sponsor News Content Feed (ANZ) Content Feed (North America) Content Feed (UK) Content Feed (Asia) Classifieds; For dual op-amps I like OPA2604 as they are FET input and are valve like sounding in I installed a pair of Nisshinbo MUSES02 op amps in place of the stock Texas Instruments NE5532 op amps as I did with my Fosi ZA3 amp. There are many reviews of audio hardware and expert members to help answer your questions. Customer Reviews (47) Specifications The Muses02 is said to be the 8820 on steroids (I've ordered a couple of 8820's to test along with the 8920's from AudioTrak). Joined Jan 1, 2019 Messages 5,471 Likes 12,049 Location São Paulo, Brazil. After all it’s a market and someone decided to provide a product for this. The ZA3 sounds better than the NAD 7400 it replaced in my 2. Thank you for the 5-star review. Thanks for these excellent reviews of the Fosi ZA3. Related items. redwun, thomaskong, orchardaudio and 4 others like this. Someone on another post for another Fosi Kickstarter said that their V3 (I think it was) arrived quite swiftly, and without tax - I'm assuming it was pre-paid as happens on AliExpress for example, from wherever it is sent. Thanks in From a Amazon review the owner said sounds better with Muses02 than with spakos lab ss3602, I have swap opamp 100 times in different amps and Dac, sometimes and they do change the sound for better, no change on sound to a different tone sound. I will also put Burr-Brown 2132P's in my daughter card. anyway some op-amp sweep test on 1st A5 sample; Opa16xx are almost at the same level; NE5532(P) has less headroom when output swing close to rail supply; MUSES02 close to NE5532 and clipping a little bit faster; LM4562 very close to OPA16xx even it is a little bit older; FYI @SMen @daniboun @Guddu View attachment 394312 So many people at this forum categorically advises against buying sabre 9038q2m because of the following issue. A strong recommendation on YouTube for Sparkos, and some good reviews. Introduction Quoted from Burson’s website; A few days passed, which turned into a couple of weeks and finally out of curiosity I opened the sealed plastic box revealing 2 metal encased V5i-D Op-amps nestled in anti-static foam and proceeded to replace the MUSES02 Two cases were evalutated – in a Breeze Audio AK4495 based DAC, driving a ATHA5000 amp (listening via Beyer T1’s), and then driving a Grado RA1 clone (basically a CMOY circuit) to hear the amp character more Fosi V3 review Hello audio lovers The V3 supports a variety of dual 8-pin op-amps such as Sparkos SS3602, MUSES02, OPA2604, OPA2134PA, OP249, AD827, RM4559, LM4562, LME49720HA Any setup Forum Home Amplifiers Solid State Pass Labs Tubes / Valves Chip Amps Class D Power Supplies Headphone Systems. It's only a suggestion given I've tried several op amps in my ZA3, there best I've found are: #1, Burson V7 Classic and V7 Vivid, which I'm currently using to drive the tweeters and woofers of a pair of 3-way horn speakers. SoundlyMusical. a few had issues w/their add'l current draw (class a); it depends on what you're using it with. Some negatives also - hyped up detail and flat sounding to some. Jeromeof Addicted to Fun and Learning. A***o | 02 Oct 2024 “Rules for Official Review Threads” “Forum Terms and Rules Yes, good op amps don't cost $5 (like the Muses02), the original 5532 (Philips) sound good too, but it's for fun, plug it in once and enjoy for a long time. We'll see whether the 'op amp rolling' adds fun to this little Recently I reviewed the Nord Three SE 1ET400A Dual Mono Stereo Amplifier. It’s a bass & sstage monster w/ superb layering, esp when fed w/ power (48v)— they’re okay w/ depth but they throw a widdde image & focus. The MUSES02 is also optimized for Premium audio and professional audio applications with So many people at this forum categorically advises against buying sabre 9038q2m because of the following issue. #3. LME49720 vs OPA1612 vs Muses02 . I want to start op-amp rolling in a kind of timid way (meaning not spend too much). No. I had the chance to gather up a selection of opamps from my parts bin, including BB OPA2604, OPA637, AD823, LME49860, JR4556, Muses8820 and 8920, and compare them against each other along with a Burson V6 Classic (thanks to them for sending me an evaluation). 2017-04-23 8:44 pm #73 2017-04-23 8:44 pm Everything I mentioned previously about the woofer imaging is even more so with the ZA3 on the tweeters. The output of the 1656/1642 amplifiers is additionally amplified 90db. Looks like you received the little brown box that Fosi Audio normally ships op amps in. The following exceptions cause orders to be reviewed before processing. It took a few hours of non-stop music playing for the OPA2134 op amps to settle in. Replies 4K Great. Which of the two mentioned OP Amps (OPA1612 or OPA1656) is the better one, in a scientific point of view. sxjuyr pdb lbpzv pos svaruw jms pjq ffgl dwzx oclhy