Tubes -vs- Class A SS...the shootout!!!

treitz3
treitz3 Posts: 19,034
edited April 2013 in 2 Channel Audio
.....And we're off! Tomorrow, I shall have a new to me Musical Fidelity AC3R amplifier. Pure Class A sand amp. This will be in place of two Anthem1 tube amplifiers.

This is not all of my rig, but will be the chain most often used...

Jolida JD100 w/12AX7 Ei Gold pins, isolation footers and an upgraded PC>
Dodd Audio MLP preamplifier w/ isolated P/S, upgraded PC, isolation footers and also has 12AX7 Ei gold pins>
Musical Fidelity AC3R w/ upgraded PC>
Tyler Acoustics Linbrook Signature Series speakers.

All interconnects, PC's and SC's TBD for synergy aspects and these components [excluding the mains] will be plugged into the Richard Grey Power supply 400Pro.

Since hearing tubes and ultimately introducing them into my rig, I have become a huge fan of the end result as to what hits your ears. There is just something magical that happens to the playback whenever I use tubes in the rig. I can tell you that the introduction of tubes have added more pleasure to my audio journey than probably anything else.

That said, for the first time in years, I will be using a sand amp when this arrives. I have read and had folks tell me that Class A sand amps are the way to go for sound and that a tube pre mixed with a sand amp is a stellar combination. As always, I have my doubts but I'm always willing to explore different ways to obtain audio nirvana.

I have had this very system hooked up to a Class A/B amplifier before [Odyssey Stratos sand amp] and while it had a great sound, the two Anthems had such good sound compared to the Stratos. To me, watts mean absolutely nothing. The Stratos had I believe around 150 watts and a boatload of capacitance. Each Anthem had 40 watts and surprising balls backing the sound, especially when the right tubes were introduced. Since I have 4ohm speakers, I will have 210 available with the MF amp. I say this to let folks know that watts mean nothing to the actual sound because the 80 [even 40, when I only had one Anthem1 amp] sounded better than the 150. I have had as little as 8 and as much as 3400. In my audio travels, it seems less is more [properly chosen].

Here's where I am with my thoughts right now. Having not ever had a Class A sand amp in the system before, I am cautiously optomistic to the change the sound will bring. In your own audio journey and opinion, will it be for the better....or worse? :eek:

We'll tell in the next couple of days and I'm going to be having a lot of fun trying my new toy out with all different types of music. This should prove to be a learning experience for me and I look froward to the end result, no matter what that may be.

That said, I do have a couple of questions concerning a Class A sand amp that those with experience could help me out with. You ready?

1 - How long would you recommend keeping it on for [from cold] to achieve optimal performance?

2 - Would you recommend keeping it on all of the time?

3 - Any other recommendations besides proper ventilation that I may not be aware of yet?

4 - I know how tube amps are affected by vibration, in your experience, how important is the isolation of vibrations with a Class A sand amp?

One other question. At this point, I do not wish to upgrade this amp. What I am concerned about is its age and whether or not I should consider replacing the caps in it. In other words...

5 - Does anybody know the production dates of when these were manufactured?
~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
Post edited by treitz3 on
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Comments

  • engtaz
    engtaz Posts: 7,663
    edited May 2011
    Leave both on for 24hr before listening. That way it will take away warm up sound misery.
    engtaz

    I love how music can brighten up a bad day.
  • george daniel
    george daniel Posts: 12,096
    edited May 2011
    Good luck Tom,, my limited experience with class A amps,, I let them warm up for what seemed like hours.
    JC approves....he told me so. (F-1 nut)
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    Gentlemen, good to hear from you both. If y'all recall, the Stratos took three days to get to where the sound was optimal so I was kind of expecting that. I have to be honest, I know nothing of the difference between Class A and Class A/B. I am looking very forward to this shootout, though!
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • VR3
    VR3 Posts: 28,654
    edited May 2011
    Thats not totally true.

    Odyssey Stratos is Class A for the first 15 watts... after that is a real fire house ;)

    But seriously... class A - first 15 watts
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    Yeah, I knew it switched at some point. I didn't realize it switched that low. Interesting.
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • heiney9
    heiney9 Posts: 25,171
    edited May 2011
    The real audible difference comes from listening to a single ended class A vs. a high bias A/B amp like the Statos. You may not notice much difference........or to rephrase that, the difference you might notice will probably have nothing to do with the "class" operation of the amplifiers on your list.

    If you truly want to compare and are interested in a traditional class A amp, it needs to be single ended class A. Not a lot of amps qualify. The ACR3 is not a "pure" class A amp. Let's not go down this path again of what constitutes "pure class A" because that has already been beaten to death with some very spirited discussion. Pure class A is single ended, end of story in my mind and a lot of others.

    Anyway, have fun because these are the kinds of listening sessions I enjoy the most. Just getting your ears on a few different pieces of gear to compare an contrast and learn is really great fun.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    So, this is not a single ended Class A. What kind is it, if you or anybody else knows? About all I know of this amp is that it has some kind of choke, which is apparently desirable.
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • danz1906
    danz1906 Posts: 5,144
    edited May 2011
    Hello,

    Is the Musical Fidelity AC3R amp pure Class A? If so, what maybe the first 5watts
    Class A?
    Linn AV5140 fronts
    Linn AV5120 Center
    Linn AV5140 Rears
    M&K MX-70 Sub for Music
    Odyssey Mono-Blocs
    SVS Ultra-13 Gloss Black:D
  • heiney9
    heiney9 Posts: 25,171
    edited May 2011
    Not even close, and I don't say that to be derogatory. Listen to it, compare, enjoy. Just because it's not single ended doesn't mean it won't sound good. I was just pointing out that it's your typical A/B topology, not pure class A. I'd be surprised if it ran more than 5-10 watts in A before resorting to A/B.

    Tom, my intention was not to diminish the excitement of a new amp, just to point out you won't be listening to a class A amp.

    Musical F, makes great, solid gear so enjoy.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    heiney9 wrote: »
    I was just pointing out that it's your typical A/B topology, not pure class A. I'd be surprised if it ran more than 5-10 watts in A before resorting to A/B.

    Tom, my intention was not to diminish the excitement of a new amp, just to point out you won't be listening to a class A amp.
    No worries, mate. I can't seem to find much information about this amp, so you are teaching me as I go. I thank you for that. To be honest, I could care less about it being a Class A amp. I would, however, knowing this....would have changed the title of the thread as it seems a bit misleading now. DOH! :redface:

    So, it seems that this would be a closer shootout between the Stratos amp I had and the MF AC3R. Eh, I'll still offer my impressions and include what I remember from the Stratos. I have a pretty good audio memory, so that shouldn't be an issue for comparison purposes.

    This is what I do know. There is a member here that I had the pleasure of listening to his rig a while back. He uses MF gear in the main rig and all I can say is that it was one of those rigs that stands out from the others, by quite a good margin. Now, I have to admit, this amp is nowhere near the power [or cost] of the one he had but needless to say...I was thoroughly impressed with what I heard.
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • heiney9
    heiney9 Posts: 25,171
    edited May 2011
    Like I said, I really enjoy hearing different gear come through my place. It's nice to get your listen on and if you have audio friends over as well to share the experience with, even better.

    You might find the MF does things more to your liking than the Stratos...........only one way to find out. :smile:

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
  • fishbones
    fishbones Posts: 947
    edited May 2011
    Good luck Tom!

    As far as guessing what will win...well, that's pretty tough for us to guess? Synergy with the other equipment, room acoustics, and your preferences of what each component offers will be the deciding factors. I've found that if I take notes while I'm listening to each component, I find a whole lot more actual differences, than when I just sit there swapping back and forth trying to take everything in at once.

    ....Enjoy!
    ..... ><////(*>
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    Well, I'll have a little treat for you to listen to when I come down. Could you possibly guess what it may be?

    Hint......it's not the Dodd MLP, even though that's coming down as well... :biggrin:

    I'm really looking forward to auditioning your speakers. :wink:
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    .....and mine.

    :biggrin:
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • fishbones
    fishbones Posts: 947
    edited May 2011
    I can't guess, but the excitement is killing me....TELL ME!!!
    ..... ><////(*>
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    ....:biggrin:
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    Good luck Tom,, my limited experience with class A amps,, I let them warm up for what seemed like hours.
    Hello again, George. First off, I'm glad you and Janice are OK after the recent storms. That said, what Class A amps do you have experience with and more importantly......why do you not have them any more, if you don't mind me asking?

    If you don't remember, I understand as you go through more audio gear than Lightman1 does women.
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • strider
    strider Posts: 2,568
    edited May 2011
    Mine turns the corner around 2 hours or so. I'd imagine my amp, at 27 wpc/8 ohms, has fewer devices to get up to temperature, however. When it's going pretty good the heatsinks are hot enough you can't touch them for more then 10 seconds, it's amazing how inefficient Class A is. Keeping that inefficiency and how it relates to my power bill in mind, I turn it off when I won't be listening to it for two days or more.

    The power supply in mine is a push-pull design, runs A all the way to its rated power in 8 ohms, and to 27w into 4 ohms then A/B to 54w; Class A maxes out at 27w into 2ohms then A/B to 108w. That's pretty much how I describe my amp when asked, I'm not real sure where it crosses the rocky crevasse that is The Definition of class A to be able to label it.

    Right now mines spiked to a 6" thick MDF turntable shelf bolted to the foundation of the house. Using 3 of Mapleshade's cheapest footer coupled to the chassis with blue tac, ended up with one under the transformer and the other two about 2" in from the front of the amp and 3" inwards. Compared to my tube pre that's spiked in a similar way, it's absolutely dead quiet.
    Wristwatch--->Crisco
  • george daniel
    george daniel Posts: 12,096
    edited May 2011
    treitz3 wrote: »
    Hello again, George. First off, I'm glad you and Janice are OK after the recent storms. That said, what Class A amps do you have experience with and more importantly......why do you not have them any more, if you don't mind me asking?

    If you don't remember, I understand as you go through more audio gear than Lightman1 does women.

    Waaaaaaaaa-- we'll have to re-think that "gear" comment--I suppose yoiu are right though---Russ(hoosier) had/has some Monarchy mono's,and I got an opportunity to listen to them for awhile-- IIRC there is a suggested "warm-ip" time--but now to the good stuff--they sounded incredibly musical,,sweet,,non fatiguing,,,he(Russ) made me a good deal on them,,and I'm sorry to say that I passed--looking back--synergy man,,I want to find/audition a good Class A on my 1C's,,as I think that it will be good match,considering the mods-blackhole etc,,something in my limited experience tells me that I need to give class a serious consideration.Back to the topic--for the pricepoint/sound value--almost a no brainer.The Monarchy's,,really responded well with a tubed pre,,they do really sing too.
    JC approves....he told me so. (F-1 nut)
  • megasat16
    megasat16 Posts: 3,521
    edited May 2011
    treitz3 wrote: »

    That said, I do have a couple of questions concerning a Class A sand amp that those with experience could help me out with. You ready?

    Congrats Tom! I am not sure the A3Cr is Class A amp or not where do you find the info it is Class A amp?
    1 - How long would you recommend keeping it on for [from cold] to achieve optimal performance?
    For Class A amps, it can take anywhere from 10-15 minutes (sliding bias kind) to an hour (pure Class A, Push Pull Class A) for warming up and sounds optimal.
    2 - Would you recommend keeping it on all of the time?

    NO! Class A amps are to be OFF or STANDBY unless you have your own utility company. But if you listen daily, you might want to keep them on for extended amount of time.

    3 - Any other recommendations besides proper ventilation that I may not be aware of yet?

    Class A amps can be heavy, just be careful not to get hurt when lifting one up.
    4 - I know how tube amps are affected by vibration, in your experience, how important is the isolation of vibrations with a Class A sand amp?

    Class A amps can be effected by vibrations also but it's so miniscule so nothing to worry about it like with the Tube Amp. Just get your Rock on.
    One other question. At this point, I do not wish to upgrade this amp. What I am concerned about is its age and whether or not I should consider replacing the caps in it. In other words...

    5 - Does anybody know the production dates of when these were manufactured?

    Unless the Class A amp has defective capacitors or abused previously, the caps in them usually last for 20-30 years. Recapping is for the really OLD amps. I wouldn't recap 10 yrs old amp unless there is a problem.


    Good Luck with your new amp!
    Trying out Different Audio Cables is a Religious Affair. You don't discuss it with anyone. :redface::biggrin:
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    megasat16 wrote: »
    ...where do you find the info it is Class A amp?
    The more I have time to research today and the more I can't find what I researched last weekend? Honestly, I have no F'n clue. I must have mixed it up with some other gear from MF, I guess.

    Thank you for your answers. As stated before, I am looking very forward to the observations of what this amp can do.
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • F1nut
    F1nut Posts: 50,572
    edited May 2011
    treitz3 wrote: »
    No worries, mate. I can't seem to find much information about this amp

    It might help if you looked for the right model, A3cr. :wink:

    I can tell you this much, it is not a pure Class A amp and the cr stands for choke regulated. Made circa 2002, so leave the caps alone.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    Thank you Jesse, I'm on it. You rock.....as if you didn't know that.
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • FTGV
    FTGV Posts: 3,649
    edited May 2011
    heiney9 wrote: »
    . Pure class A is single ended, end of story in my mind and a lot of others.

    Well even your hero NP has suggested differently.:wink:
  • dorokusai
    dorokusai Posts: 25,577
    edited May 2011
    1. 2 hours.
    2. No.
    3. No.
    4. I like to isolate all my components aside from my amplifier. It's heavy enough that it doesn't matter but in your case I'd get it on a sandbox. There's no reason to replace the caps on that unit.
    5. MF A3CR....2000(Audiogon) to probably 2004? when the 3.2 came out. I'm guessing but it should be close.
    CTC BBQ Amplifier, Sonic Frontiers Line3 Pre-Amplifier and Wadia 581 SACD player. Speakers? Always changing but for now, Mission Argonauts I picked up for $50 bucks, mint.
  • heiney9
    heiney9 Posts: 25,171
    edited May 2011
    FTGV wrote: »
    Well even your hero NP has suggested differently.:wink:

    Not really, but I'm not going down that discussion path again. :smile:
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
  • treitz3
    treitz3 Posts: 19,034
    edited May 2011
    Would that be Mr. Nelson Pass? I must have missed the conversation.
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • FTGV
    FTGV Posts: 3,649
    edited May 2011
    heiney9 wrote: »
    Not really,
    Brock,he gives his XA.5 series the Pure Class A moniker whilst they utilize a push/pull ouput stage.
    I also believe I have read his definition of Pure Class A is when an amplifer has a continuous power draw (even at idle)that is equal to or greater than twice the rated Class A output.
  • Poee7R
    Poee7R Posts: 904
    edited May 2011
    Class A, B, C, yada, yada, yada. Plug the thing in, if it sounds good, what else is there?

    I will say though I am a bit envious, I was eyeballing that listing also. :tongue:


    Dave
    Once again we meet at last.
  • megasat16
    megasat16 Posts: 3,521
    edited May 2011
    FTGV wrote: »
    Brock,he gives his XA.5 series the Pure Class A moniker whilst they utilize a push/pull ouput stage.

    I believe it's where he called "Leaving Class A" and the paper explains the intent clearly.
    I also believe I have read his definition of Pure Class A is when an amplifer has a continuous power draw (even at idle)that is equal to or greater than twice the rated Class A output.

    But to some, Pure Class A is not about power draw, not about output wave, but about Single Ended Output Stage and nothing else matters. :wink:
    Trying out Different Audio Cables is a Religious Affair. You don't discuss it with anyone. :redface::biggrin: