My Fosi Audio TDA7498E has PRAT up the ying yang. If the song has it that is. Paired it with appropriate speakers or DAC to take the edge off I would challenge anyone not to react to the rhythm this thing puts out.
Could Class D really be that good?
I've heard statements praising modern class D amplifiers all the time but was sort of hesitant to try. Lately, one particular model caught my eye, the Fosi V3, which costs sub $100 but is praised for having refined sound like class A/B. To fulfill my curiosity, I quickly ordered one and tried it with my Burchardt S400II and Wharfedale Linton speakers. Basically, this is a neutral sounding amp but, to my surprise, the sound is clean, open, airy, with full mids, wide soundstage, good imaging/separation, with nearly null traces of the edginess, dryness, or lean sound that traditional class D amplifiers have. The background is just as quiet as my current systems. The core is the TPA 3255 chip from TI and comes with a 32v, 5A power block, which is supposed to deliver approximately 65 watts per channel (into 8 ohms). It drives the S400II/Linton without any hesitation, as well as my 130-watt-per-channel high-current Parasound A23. Very impressive.
Measurement is not everything. However, according to the lab test results, when operated under 10-60 watts, the distortion level (THD) is below 0.003%, better than a lot of high-end (price) gears. I am going to build around it for my fourth system with upgraded op-amp and LPS. I believe it will outperform my current mid-end (price) amplifiers.
I know, I know, quite a few Audiogoners' systems are above $100k, and mentioning this kind of little giant that costs a fraction could be rather embarrassing. But I thought this is just like gold digging with a lot of surprises and fun. Don't you think?
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About a year ago Michael Fremer (who seemingly can have whatever he wants) reviewed PS Audios M1200s, class D with tube input. He kept them
Over 2 years ago I bought custom EVS 1200 dual mono based on the same ICEpower AS1200 modules, but lots of tweaks. Really excellent amp. How good it can sound depends on the rest of the system |
@eddnog Did you also receive two complimentary MUSES 02 op amps? It would be interesting to compare those with Sparkos... |
This seems like a serious thread from people who have really done a lot of work with op-amps over on ASR. Seems like there are a lot of gotchas if you don't choose and test carefully. Objective changes for the worse or better in terms of noise and distortion seem to be readily measured. Subjective preference of course is up to each listener.
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Agreed on the audible improvements, though I'm not sure about measurable evidence, as I couldn't find any supporting data. Nevertheless, I recently swapped in an op amp called "Oracle II dual" on the Fosi V3, based on the recommendation from VirtualHiFi. https://www.youtube.com/watch?v=kNDX7SCN6Jc These Oracle op amps were made in China and shipped from there, so the wait time might be a bit longer. However, they arrived earlier than expected. The build quality seems better than most cheap op amps, which often have flaky pins. The No. 1 pin, which needs to be aligned with the notch on the riser supporting the default op amp, is marked by a dot on the upper face. Ensure you have oriented it correctly. Other than that, the installation is pretty straightforward. Immediately after switching on the "new" Fosi V3, I noticed a more immersive soundstage that extends beyond my speakers, with noticeably better separation. The bass also goes a bit deeper. However, it still doesn't completely eliminate the undesirable sibilance. But, considering these are $28 op amps, I might be asking too much. The well-known Sparkos 3602 might perform better, but it costs more than what I paid for the amp. Overall, my experience with the Fosi V3, paired with the Oracle II and Wiim Pro Plus combo, is very positive. I would recommend it to anyone looking to explore low-end (pricewise) Hi-Fi gear without reservation.
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I don’t know how to get those results that will put my name in lights. If I did, I’d do it. The method is easy, just do double blind tests on signals that measure identically and show that people are statistically identifying them correctly as different. The method is easy. Getting the result is the hard part. As for op-amps, if you just swap different op-amps in and out of a circuit, it is not too unlikely that significant changes might occur that can be audible - and measurable. Op-amps need to be in a circuit designed for them to be transparent. So yes, it is generally agreed that if you want to tweak the sound, you have a good chance of doing so by randomly popping new op-amps into a circuit without adjusting the circuit accordingly. You may hear something you really like! |
The reason someone in 2003 would say that is we all wanted hi rez....and the only hi rez then was SACD and DVD-A.....and you then needed an SACD player as Sony would not allow digital out of the DSD signal. So, I started modding SACD players.....because that is what everyone wanted. Of course, when downloads started to happend and then streaming.....then DACs came back into vogue. Now there are a lot of integrated amps, streamers and powered speaker that have DACs built in but the DAC game is still alive and well. Look at the raves over the new cheap Holo and the Laiv DACs. If I were looking for a solid state amp in the under $3K range than the Purifi, Orchard, NCx500 and Nilai (stock, and of course, modded) fill the bill. However, if you want to spend twice as much, then you have the AGD Tempo and tubey dude, the Atmasphere and the Coda 5.5 to consider. I would never buy one of these amps without comparing them all. They all have rave reviews but hardly any comparisons. Most amps can be purchased with a 30 day trial.....of course, you have wait times for some amps......like the Coda. Even more expensive would be the bigger AGDs. the Merrills, the hopefully about to be released Mytek, etc......and of course, you can combine a class D amp with a tube preamp or input stage to give that tube magic. |
+1 @arafiq
@grk both these companies have been creating products for quite some time and have CURRENT products in the market. In fact I OWN the Backert Labs Rhumba. Based on a claim made here, I looked up searched the internet on "EVS Millennium DAC". A result came up on Audio Circle on the "EVS Millenium DAC" thread. It is from 16 Mar 2003, 07:42 am and the poster says - "Dacs are increasingly becoming obsolete (in my opinion)". Wow..so true in 2024...LOL!! |
How you view the world is a reflection of how you view yourself. The universe is your mirror. More and more I love what I see. I don’t always like it......but even the likes/dislikes are fading in the sunshine of your eternal love. It just feels so good to love.......we never have to stop. God (dog backwards), help me to see that your love is always present and that I am always loved and adored. |
riccitone, What is your direct experience with the Nilai amp that makes you state what you did? Did you compare it directly to stock or modified Purifi, high powered Purifi, NCX500, Orchard, LSA, Peachtree, ICE and Pascal? I did mods to a Nilai but when I did the mods (pictures of modded Nilai on my site) my system was not working so I could not A/B with my modded Purifi to find out how good it is relatively. I know what the mods do....I have done the same mods to many amps and the results are always a better sound. |
@arafiq "So on one hand we have a designer/builder/entrepreneur who has been building and selling top quality products for a number of years. On the other hand, we have a ..... tweaker, who modifies other people's original designs. Hmm... who is right? Tough choice man!" Hmm... tell that to Dan Wright of "Modwright" and Bob Backert of "Backert Labs"!
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It is not questionable that we need the designers. What folks like ricevs and angela gilbert yeung do is " take a design that they like ", and simply improve upon it. Anything can be improved. A few years ago I was contacted by a friend of a friend, who wanted me to work on an older, very high end ss amp, retailing about $20K when introduced. My reputation proceeded me😏. All six sides of the chassis, the heatsinks and many other areas inside were so tinny and resonant. The top panel and heatsinks were an embarrassment for a 20K amplifier. Ring ring ring . Anyway, I damped the crap out of it, changed out the rubber feet, created a quieter mechanical isolation between the transformers and the chassis, and so on and so on. These damping mods are more in line with what angela gilbert yeung does. ric might or might not get the idea, as he and I have discussed this matter here. To say that this owner, and might I say, listener, thought he was hearing a newer, more modern version of his amplifier. Cleaned things up. I did not change any parts, except the feet. Everything matters. There are a few different kinds of attitudes here, with the most irritating being those that do not believe...., or can’t hear, or have an inferior set up / system, or never tried, just believe science. Those who have not tried, for an example, an upgraded power cable. $50. bucks on Amazon, please see the thread, "A Stupid Question About Power Cords". I reveal it there. It is under the Amps and Preamps category. To build a cable superior to this, it would cost me more than the $50. With a return if you can’t hear the difference, and get your ears professionally cleaned and your hearing checked. Enjoy ! MrD. |
The one with the truth is the one with the truth. Does not matter what the backround is of a person. By the way, I have manufactured DACs, amps, and passive preamps.....see EVS Millennium DACs on Audio review....had my passive preamp rated class A in Stereophile for 7 years......worked for Monster Cable, MFA, Sota and have had my own audiophile company since 1989......I bean around the block. It is not about taking sides.....it is about truth. What I say is true....and thousands and thousands of audio designers, engineers, and audiophiles from all around the world agree. What Ralph says.......very, very few agree with. Who is right does not matter.....what matters is that we know what is true. Again, test everything yourself. Have you tried different op amps and listened? Have you tried different passive components and measured them? If not, what do you know? This is not about wanting someone to be right or wanting something to be right.....this is about what is true. And the only way you know what is true in audio is to listen.......choose your favorite components with your ears.......choose your audio knowledge with your ears. As I said before, do not believe anyone....if you do then you are a SHEEP.....just repeating someone elses thoughts......do your own research.....be a smart person.......be self motivated....think for yourself. And most important of all....love yourself and everyone with all your heart and soul. |
asctim, I hereby assign you to the task you want me to do. You surely want your name in lights because you talk about it. Please, get to work now.....please try to prove the unprovable.....good luck. Love grows by attention to love. Give everyone more attention....this is the way love grows......"Shower the people you love, with love....show them the way that you feel"........the people you love is everyone.....Every single person you meet from this moment on.....wants something from you......this reality is now imbedded in your brain from this moment till eternity......and what they want is to be loved and noticed and appreciated.....every single person. The only reason why there is violence and lying and anything negative.....is because someone feels unloved.....pretty darn simple.....but it is hard to remember to be loving in every circumtance. This is our task.....to grow in love. Keep loving......never stop loving. Start in the morning by looking in the mirror and gently stroking your face and tell yourself outloud how beautiful you are and how much you love yourself....smile at yourself......Do this as much as possible everyday....will change your life......then when you do this to others it will blow the whole universe to pieces......OMG....I love you so much. |
Ralph, Prove it. Show us the measurements and the correlating listening tests.....you cannot. You just have Myths that you make up. Yes, it is not published because it does not exist. The only thing tricky is your mind here......you cannot fool anyone. You need to show proof. Your words are tricky (reality is real).....show us the beef! Show us the measurements that show how all op amps sound different.....since everyone who listens thinks they sound different. If they sound different there must be a measurement (according to you). But, of course, to you they all sound the same.....so why measure. How long will you keep up this charade? Till death do you part? Are you married to your opinion? Can you laugh at yourself? Can you feel the love and bliss that exist right now? |
@asctim I can't seem to convince that guy that what he's saying about me is wrong. 🙄
This was true back sometime in the 1980s. But measurement tech like nearly all other technologies has improved quite a lot in the last 30-35 years :) But many people don't realize that, and worse yet, wouldn't understand the import of the measurements if they saw them- and quite often, they are not published. So the myth (as purported above) continues. These days there is a direct line between what we can hear and what we can measure. The tricky bit might be understanding what to measure... |
This is not a discovery. Those that have listened, have known this since audio reproduction and measureing equipment were invented. Most things that make a sonic difference cannot be measured.......plain and simple. Why would I care to convince some science measurement addicts that this is true. Its maybe 20% of people who think of themselves as audiophiles who believe that way. I say, let them have their playground. But when they come into our commonly heald public presence.....and speak their non-listening.....no real empirical knowledge BS.....then we need to speak our listened to truth and wish them a nice journey. The ego is very stubborn......ever heard the term "dead right". A non believer will not even attend a listening session with believers (try inviting Ralph to your op amp rolling listening session).......If they heard a difference then they would have been wrong all this time and if they told everyone in the room they heard no difference....then those people would think they are deaf or stubborn and never trust what that person says from that point on. The ego wants to maintain the status quo.....if you say in public the sun is blue....then your ego will defend that position till you die or admit you were wrong......and who wants to admit they were wrong. The whole problem here is false identification. We think we are our bodies, feelings, thoughts, sex, race, religion, etc. WE are NONE Of that. We are infinite spirit. We don’t need to cling to thoughts and "protect" ourselves from each other......WE are truly all one......one big blob of love. The mind cannot hold this infinity that we are....so we pretend we are less than the all that is and judge ourselves and everyone. When you realize that you are the MOTHER of all creation (creating every single thing you experience and that everyone experiences)......and also everything in the whole universe is ALSO the MOTHER of all creation......and that creation is happening every single second of the forever that we are......it changes you.....You treat everyone and everything as your BABY, your young chiild, your pet....your ultimate lover. Divine mother is everywhere. You are divine mother......Happy Mothers day.......it is always mothers day. Kisses and hugs. |
The measurements don’t change but anyone can hear a difference? This is a huge discovery, and understanding what is going on will advance science. If you can figure out a way to show what it is we are hearing with some new measurement your name will go down in history. Heck, if you can even demonstrate that people are hearing a difference in well conducted tests, and nobody can measure a difference, that alone will get you in the history books. We’ll have a huge scientific mystery to look in to. You’ve got to do it man, for the sake of scientific progress! If you get good data out there, even the most resistant, hardened skeptics will have to relent. In time, they'll thank you for it. |
I knew you could not leave it alone.....you had to have the last statement....so, i will not comment and let the readers here decide for themselves who has truth and who is blowing smoke. If you want to know something about anything.....then do some research. The internet is a vast wealth of knowledge......but one persons opinion means very little. Don’t be a sheep or a lemming.......After finding out what MANY others say then find out empirically *with your senses" what is true, for YOURSELF. Listen and know. Do not believe me or anyone. Do your own research.....be your own creator, your own God.....for we are made in the image of the almighty. We CAN KNOW for ourself, what is really true about anything......including what is our true spiritual identity/reality......In MY EXPERIENCE......we are all love. and incredibly beautiful and amazing. The truth shall set you free......free from your ego mind.....free from worry.....free from death.....for we are eternal. Happy forever! |
The above statement is false. Here is what I actually said:
That isn't me saying 'any modern opamp has no sound'! What I am saying is that if you know how to design with opamps, and if you compare high performance opamps, then you will not hear any difference other than perhaps the noise floor. I know there are companies that make a living selling opamps based on them having a 'sound'. But any engineer finds that sort of thing to be a facepalm event. It means either the opamp is poor performance compared to what is readily available (and probably for a lot less money) or the circuit in which it is used is poorly designed, or both.
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Hypex Nilai renders a new level of sonic refinement over the pre ious modules, ice power included. The most underrated out there atm. I’m looking forward to getting the diy kit for the Nilai 500 amp myself. |
I do not run a class D amplifier, so take this with a grain of salt.....though it does apply IMO. A tube preamp (or preamp section), can mate extremely well with solid state amplifiers. I have the recently updated CODA S5.5 class A SS amplifier that is truly a marvel, and was initially driving it with a Denafrips Hades preamp.....which is much better than I ever gave it credit. I recently added an Aric Audio Motherlode XL preamp, and my god what a revelation. I'd consider a tube preamp, or an amplifier with a tube input stage....it might be the best of both worlds for you |
grk, Thanks for that link. Probably? using the Orchard GaN modules after the tube in the smaller amp. $3600-$4000 is a nice price range. You can get a tube front end on the high powered Purifi from VTV for about $3000. Lots of cool stuff out there. The 300 B version has no price yet.......probably $5K or more. |
Wow, that is the best you can do. You just stated above that any modern op amp has no sound (will not change the sound). No sound is most peoples definition of "perfect"...or perfectly transparent......Again.....the people who listen do not agree. Now what little thing that I just wrote will be your next victum of you ego defense mechanism. Give it a rest....please. If you keep saying untruth.....then I will have to counter with truth. Please, all there is is love. Please do more listening and post some listening test truths. This will be most helpful. |
Wow, you just stated that all modern op amps are perfect. Yes, you did not state that all opamps made since the beginning of time were perfect (yes, I did not quote you correctly). What you stated before was just what you said: "all modern opamps".....you probably mean after 1980?....I quess that is when you stopped listening. All "modern" op amps have a sound and it is not confimation bias or a bad design flaw. This is where thousands of people (including world class designers) disagree with you. They know that certain brands of op amp sound differently (and most believe discrete op amps are the most transparent). But you have to listen to know.....something you do not do (at least with op amps). The changes I do to class D amps lower the perceived noise. You hear farther into the recording.....more decay, more ambience, better imaging, more correct harmonic structure, more transparent and real......this is REAL noise reduction.....not some number on a graph. I do no know more about basic design than most designers, however I have more practical knowledge of implementaion and parts and how they affect the sound than most designers. I have been doing listening tests since the mid 70s....and was the first person (back in the late 70s), that I know of, that did straight wire bypass tests on wire....yes, no wire was perfect.... The companies that usually make the best sound do both....they design and they tweak like crazy. That is why they keep updating their stuff.....like the guy at AGD. Check out this page on Burson Audio. Go to the bottom of the page and see all the pics of customers products that were upgraded using their op amps.....you can keep loading more and more and more of them. These people have circuits that are flawed and they have expectation bias?.....come on......This is just the tip of the iceberg worldwide. At the top of the page are Utube reviews of the op amps. You can keep making stuff up and believing it and telling the world about it.......but it is not truth unless it passes the listenng tests. The people who have listened do not agree with you. Burson is now in their 7th generation of discrete op amp....they never stop tweaking....for they know there is no perfection. it is a goal. When you get to the top of the mountain......you look for higher mountains to climb......same with our soul. Love is infinite......the more you eat....the more hungry you become. It is the ULTIMATE ADDICTION.....bringing the highest joy......for everyone.
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Not to put too fine a point on it, but when you can change an opamp (if its modern, hi performance) and hear a change (other than noise floor), one of two things is happening: 1) confirmation bias, or 2) the circuit has a design flaw. Opamps have seen a lot of evolution over the last 75 years; guitar stomp pedals and synthesizers from long ago won't sound right if you install newer hi performance ICs instead of the original types. This is because older opamps indeed have a 'sound'. Modern ones do too if you don't use them correctly. Put another way, the statement in the quote above is false; I never said that 'all opamps have no sound'. Clearly you don't read my posts or you would know that. Anyone can open a class D amp and change how it sounds! Quite often their changes result in greater noise. From your posts it appears to me as if you think you know more than other designers. So its curious that you haven't designed a module of your own long ago! |
The statement from Greg just shows his ignorance. Of course, you do not need to have matched fets at the input of your class D amp.....you can just use inferior sounding integrated circuit ICs.....he he. He does not listen to parts and execution in his class A/B amps nor in his class D amps. NAD is not a high end tweak company like VAC, AGD, Aavik, Gryphon, Merrill, etc. These guys listen to everything including the parts and execution in their class D amps......as stated above about AGD and Aavik. Just read the review on 10 Audio about the NAD C298 Purifi based amp and then read his review of my modded VTV Purifi amp (which costs less with the mods than the NAD does stock). He rated the NAD at a 6 (extremely low rating from him) with mine a 9.5 bordering on a 10. You can keep quoting people who do not tweak all day long but it does not stop the truth as known by actual listening tests.....Emprical knowledge.....directly experienced listening tests are the ONLY proof of transparency......not what someone says (including me) on a forum or what someone believes. Everything makes a difference......and that includes the parts and execution in class D amps. The latest rage Fosi and Ayima cheap amps using the TDA 3255 class D chips all have sockets for changing the op amps that are buffers before the class D chip. People all over the world have changed those op amps and get different sound.....You, however claim that in a low gain circuit that all op amps have no sound. You are again a minority of one here.....thousands of audiophiles and manufacturers would disagree. Look at all the Purifi and Hypex amps out their that are being sold that offer different op amp choices. They are not doing that to just make money.....but to tailor the sound. Again, everything makes a difference. |
https://pmamagazine.org/is-class-d-amplification-now-better-than-class-a-b-and-class-a/ (Emphasis added) Greg put this pretty well. |
@jl35 glad can of some help. enjoy listening. |
Class D amps have been getting better and better. You have the "all you need is more feedback to lower the distortion" people....Bruno, for instance....and you have the "all you need is a certain kind of distortion" people ......Ralph, for instance..... you have the "all you need is a tube buffer to sweeten it up" people....PS Audio, for instance, you have the "We are using the best Ganfets....all the rest use junk" people.....AGD for instance, etc. However, it is not just one thing.....this is what I say over and over. AGD has had two updates to their "tubey thang" and everyone agrees the latest is the best sounding.....they are still using the same "magic Ganfets" they used in the original version. Look at the Aavik amps that use the Pascal modules.....they have different versions of the basically same amp but they add more "active Tesla circuits"....more dither circuits, use a more damped and low hysteresis chassis (made from copper) and use more tweaky feet in their more expensive ones.....same Pascal module used in each one.....but all the reviews state the more expensive ones sound better. So, they are selling you more tweaked versions. This is exactly what I do to Purifi, Ncore, etc. amps......I tweak them to make them sound better. They will not measure any better.....just like the various more expensive Aaviks don't measure any better.....they just sound better. The new $10K Ganfet amp from Mytek has been promised for over 3 years......but supposedly is starting to ship soon?....he he. Like waiting for Godot. Laiv audio is said to be working on a GAN class d amp. Their new $2700 Harmony DAC is the latest rage. . It is interesting that Aavik now has a class A amp as their reference amp....so they think class a is still the best (well, for $70K, it better sound great!). However, they are using a stock? Pascal module in their class D amps. What if they used their own super class D circuit or one from AGD or Purifi or Ralph or whatever? Still much more evolution to be had here. Class A transistor amps really started to get tweaked back in the late 70s......class D really on has maybe10 years of serious tweaking. Here is a link to a post on Audio Circle where two people describe the difference between using the stock polyester Wima output filter caps and my modified Polypropylene Wima caps. The comments worth reading are on the first page and the last page......everything in between is mostly people arguing about nothing |
@atmasphere Ralph, great post and thank you for sharing. I also enjoy your afternoon talk here, which helps me understand some of the intricacies of class D design. |
For those contemplating the question of this thread, you aren't the only ones: https://pmamagazine.org/is-class-d-amplification-now-better-than-class-a-b-and-class-a/
Yes. Not worth worrying about on weekends. |
@jl35 They are pretty much the same based on my recollection after seeing several reviews and demos. I decided on v3 primarily because of its pre-out feature, so I could do bi-amping later on with other class A amp. |
I am with ricevs. As I do with many pieces and doing it for over 50 years, I finally got around to chassis damping my LSA GAN 350, including changing out the stock rubber feet. What I hear now vs stock, are cleaner, faster and more agile sounding transients, more air around the instruments, greater articulation with the "playing" of the instruments, and greater dynamic contrasts. The rear panel alone was very "alive and ringy", and now it is dead silent. The power cord, interconnect cables and speaker cables all have a quieter environment to contend with. Everything makes a difference in what I hear. Could care less if it is measurable. GANFETS, to my ears and in my system, are the most enjoyable class D I have heard, and in the last 18 months, I have heard many. My best, MrD. |
I did try the 48-volt PSU, but the truth is, it doesn't deliver better sound than the 32-volt PSU at normal listening levels or even at 80-85 dB. Surprisingly, the 32-volt PSU offers cleaner sound, leading me to believe that it is the better and less noisy SMPS option. Moreover, in terms of power requirements, the 32-volt PSU proves to be more than sufficient for a small to medium-sized room. The 48 volt psu also drives the amp unit noticeably warmer than the 32 volt which will potentially shorten the left span of the amplifier. Not recommended. |
Ralph, It took you two days to reply and that is all you can come up with? You will say anything just to make me look bad so you can feel you are right.....wow! The two statements are not contradictory......I said "if it changes the measuremets". Again, never implied it did. You are just making something up to make me look bad, so that people might dismiss the fact that you stated something untrue. You are lying.....plain and simple. You cannot measure the distortion in high end used passive components......that is a lie.....and you know it. You have never proved that you can....and no other designer (that I know of) has ever said this except you. The only way you can prove you are correct is to show measurements. The only intelligent (non ego driven) response to this post would be that:.....your measurements....your quotes from others who have tried this and show their measurements. Any other reply would just be from your ego.....(defending your postiion...without proof). So is the statement you made true? If so, prove it. Othewise it is a lie. Why would someone make up stuff and post it online? I try to state what I know about....that is directly experienced or relay info from others who directly experience stuff. I wish you well, but stating something on a public forum that is not true and then defending the statement by trying to make someone look bad who points out your untruth (rather that prove your original statement).....does not help your reputation. Why would I trust anything else you say if you just make up stuff and post it? Now you are saying 6N copper is a myth. Can you prove it? Is this a belief or a BE LIVE? Please show us the measurements. From what I read, the claims of 7N and 8N are made up, but 6N can be real. All wire sounds different no matter what the amount of claimed Oxygen free level. A single piece of wire will sound different depending on the direction it is used.....even PCOCC wire. All above sonic statements tested with my ears....so it’s a BE LIVE. Belden make the Iconoclast insterconnect cables and those guys are VERY scientific.....however, they make three different versions....pitch copper, OFC and PCOCC. They go up in price accordingly. Every one who has reviewed them agrees that the PCOCC ones sound the most transparent. Everything makes a difference....my usual statement. And Everything is LOVE.....the statement of the Universe....every second. Enjoy. |