Geoff gets a new amp!

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  • 11-13-2010, 06:39 PM
    Geoffcin
    Geoff gets a new amp!
    Actually it's a lightly used Ming Da MC34-AB;

    http://www.coemaudio.com.au/images/p.../mc34ab-01.jpg

    Geoff is very happy!!
  • 11-13-2010, 07:22 PM
    Mr Peabody
    I'm not familiar with that brand. How is it an improvement over your current one? Getting new gear is always fun, congrads.
  • 11-13-2010, 08:04 PM
    dakatabg
    I would be happy too
  • 11-13-2010, 08:42 PM
    Geoffcin
    Quote:

    Originally Posted by Mr Peabody
    I'm not familiar with that brand. How is it an improvemeMnt over your current one? Getting new gear is always fun, congrads.

    The company, Meixing MingDa, makes many other branded amps, this is their design. Basically it's a dual mono PP design with 4 EL34 tubes per side. On this particular unit all the tubes have been rolled, with 2 NOS Mullard AT7's, 2 NOS Sylvania 6N7GTB's, and 8 of the newly designed JJ E34L output tubes.

    Just from a cursory 2+ hours of playing with it the performance upgrade from my last amp is not subtle by any stretch. I
  • 11-14-2010, 05:09 AM
    Feanor
    Wow! Looks great. I'm envious.
  • 11-14-2010, 05:40 AM
    Geoffcin
    Thanks! Actually this was the amp I originally wanted when I bought my first tubed integrated but I didn't have the faith to shell out the coin the first time around.

    Really this amp is a step up in so many ways it's not funny. We quite literally had a disco party going on here last night. You wouldn't think maggies as club speakers but this amp has so much "grunt" that we had the place shakin like the love shack, and some seriously silly dancing ensued!
  • 11-14-2010, 05:57 AM
    Feanor
    Quote:

    Originally Posted by Geoffcin
    Thanks! Actually this was the amp I originally wanted when I bought my first tubed integrated but I didn't have the faith to shell out the coin the first time around.

    Really this amp is a step up in so many ways it's not funny. We quite literally had a disco party going on here last night. You wouldn't think maggies as club speakers but this amp has so much "grunt" that we had the place shakin like the love shack, and some seriously silly dancing ensued!

    At 75 wpc, ultralinear, that Ming Da is adequate to drive Maggies at reasonable level, IMO. (See Pacific Valve's spec HERE.)

    It's my ambition to build a nice tube power amp kit; say maybe Bob Latino's Stereo 120, HERE. The contrast with my current class D amp is likely to be stark.
  • 11-14-2010, 01:18 PM
    JoeE SP9
    Talk about eye candy! That's one nice looking amp. It must have some real grunt power. Having a "shake yer booty" party with it driving Maggie 3.6R's says a lot of good things about it.

    .:yesnod: For once I agree with "Pixie". :biggrin5:You should get rid of that antique. :idea: Send it to me so I can dispose of it properly.:ihih:
  • 11-14-2010, 04:22 PM
    Geoffcin
    Quote:

    Originally Posted by Feanor
    At 75 wpc, ultralinear, that Ming Da is adequate to drive Maggies at reasonable level, IMO. (See Pacific Valve's spec HERE.)

    It's my ambition to build a nice tube power amp kit; say maybe Bob Latino's Stereo 120, HERE. The contrast with my current class D amp is likely to be stark.

    I've actually emailed back and forth with Bob. The product he makes is light years ahead of the old Dynaco that it's based on. His 10k square wave looks better than the old Dynaco 1k wave. I was on the fence about if his amp was enough for my maggies, but after more than a year now with tube amps I can say unequivocally that a 60w tubed amp should be enough for nearly any speaker.

    The Ming Da is rated for 75w with the old Jinvina tubes, but these rolled output tubes are the JJ34L's and pack a good 10%-20% more punch. In addition, the dual mono power supply adds at least 25% more "guts" to any amp that I've ever heard, my Musical Fidelity A3cr as case in point. I'm a big fan of both dual mono design, and separating the AC rectifier from the main chassis like my PS Audio IV preamp does. The Ming Da does both!

    I'm listening to some David Sanborn right now, and I've never heard this so good though my maggies. The notes of his sax are just hanging there in the air, you feel like you could reach out and touch them!
    http://ukrmedia.biz/images/products/..._here-gone.jpg
    It's like having my listening room turned into a jazz nightclub!
  • 11-14-2010, 04:45 PM
    Geoffcin
    Quote:

    Originally Posted by JoeE SP9
    Talk about eye candy! That's one nice looking amp. It must have some real grunt power. Having a "shake yer booty" party with it driving Maggie 3.6R's says a lot of good things about it.

    .:yesnod: For once I agree with "Pixie". :biggrin5:You should get rid of that antique. :idea: Send it to me so I can dispose of it properly.:ihih:

    Hi Joe, thanks! Yes, this is one pretty piece, but it's not all skin deep looks. The internal build is at least as good as any tube amp I've ever seen.

    Joe, the guy I bought it from, is one of the "gurus" of tubes. (he had quite literally 100's of NOS tubes everywhere!) Before he even agreed to sell me the amp I had to learn the ways of perfecting bias. To say this guy was a perfectionist is really an understatement. Taking about 15 minutes and several readings we got the bias for all 8 tubes within .5%. That's 1/2 of 1 percent! With his tube rolling to an all NOS front end he has really tweaked this amp to about as good as I could imagine anyone could, and it shows!

    Guys like him love projects, and I am the happy recipient of this one. Now if I can just get him to make one of his walnut plinth TT!
  • 11-14-2010, 05:13 PM
    poppachubby
    Wow, right on Geoff. I was over at my tube tech's house the other day to pick up my EICO. He has a pair of HF-60's which are super dynamic and loud. Your amp looks like a pair of those in one chassis. If it sounds anything like the HF-60's, then I know EXACTLY what you are hearing. He has an LP-12 with Ekos arm and it sounds damn near like heaven.

    Did you get rid of any amps you already had to make room?

    Where does it bias from, underneath?
  • 11-14-2010, 05:30 PM
    Geoffcin
    Quote:

    Originally Posted by poppachubby
    Wow, right on Geoff. I was over at my tube tech's house the other day to pick up my EICO. He has a pair of HF-60's which are super dynamic and loud. Your amp looks like a pair of those in one chassis. If it sounds anything like the HF-60's, then I know EXACTLY what you are hearing. He has an LP-12 with Ekos arm and it sounds damn near like heaven.

    Did you get rid of any amps you already had to make room?

    Where does it bias from, underneath?

    Exactly my thoughts! The Eico gets a full 60wpc out of two EL84's in PP configuration. How this amp is rated at only 75wpc using 4 output tubes per side doesn't make any sense.
  • 11-14-2010, 06:08 PM
    Geoffcin
    Quote:

    Originally Posted by poppachubby

    Did you get rid of any amps you already had to make room?

    Where does it bias from, underneath?

    I've still got my Ming Da MC 368B90 amp in addition to several SS amps that are doing duty in any number of systems. The funny thing was that I JUST rolled the output tubes on the 368B90 to Tung Sol 6550's literally just hours before getting the chance to get the newer amp, The 368B90 is an incredible amp. I would say that it would open the eyes of any SS guy to what tubes are all about no matter what SS amp he was running. I had a year with it, and for the most part I was happy as a clam. Of course when the upgrade bug bites there's no fighting it.

    Yes, you've got to open the unit to bias it. Joe designed a block to let you flip it on it's side to do this.(of course he gave me that too) He even showed me some of the other internal features of this amp like the teflon sheathed pure silver wiring used for the input signals. They really spared nothing in the design of this amp. Heck, even the chokes are shielded!
  • 11-14-2010, 07:42 PM
    poppachubby
    Cool. Yes my Golden Tube biases from the inside also...misery loves company, so welcome!! What voltage do the tubes run at?

    I am glad to hear positive reports about Maggies and high powered tube amps. My long term plan has been to go dual mono with another SE40 and get a pair of Maggies. The thing is, my full rangers may divert me from making the jump to Maggies. We'll see...

    Next time you're inside that thing take some nudies.
  • 11-15-2010, 03:29 AM
    Geoffcin
    Quote:

    Originally Posted by poppachubby
    Cool. Yes my Golden Tube biases from the inside also...misery loves company, so welcome!! What voltage do the tubes run at?

    I am glad to hear positive reports about Maggies and high powered tube amps. My long term plan has been to go dual mono with another SE40 and get a pair of Maggies. The thing is, my full rangers may divert me from making the jump to Maggies. We'll see...

    Next time you're inside that thing take some nudies.

    I'm OK with having to open the unit up. Makes me feel like I'm a tech and not just a punter with a multimeter. There's plenty of good pics of the insides of this amp. Really quality point-to-point wiring.

    http://www.pacificvalve.us/images/Mi..._Cover_Off.JPG

    You can see the eight pots for adjusting the bias. I'm not sure what the rail voltages are, but we biased the tubes to 3.5v. I was told that these more robust JJ tubes could stand 4v, but why compromise the life of the tubes for a few more watts?
  • 11-15-2010, 08:34 PM
    Mr Peabody
    I'd really like to hear that amp. Have you compared the triode mode as far as sound quality?
  • 11-16-2010, 03:42 AM
    Geoffcin
    Actually I haven't tried the triode mode yet. I did play some Dave Brubeck last night, so I'll do an A/B with that recording to see how that sounds.
    http://www.richardbealblog.com/wp-co...rubeck.gif.jpg
    It's an HDCD encoded disk and one of my best. You can hear right down to the master tapes noise floor!

    An interesting point to ponder; I played my 20'th Century Masters CD of "The Who" and it was un-listenable. It appears that the CD is recorded at a very high level, and with my CD player, which outputs a higher and non-standard 2.5v, drives the Mullards into distortion. Honestly I thought I had broken the amp! A quick change to an Anita Baker CD proved this to be wrong, but it appears that some CD's will be off limits with my setup now.
  • 11-16-2010, 03:51 AM
    audio amateur
    Ouch. 2.5v isn't even that high... I'm guessing no volume control on the CDP?
  • 11-16-2010, 04:55 AM
    TheHills44060
    Are you using the 4 or 8 ohm taps on the amp?
  • 11-16-2010, 07:33 AM
    Geoffcin
    Nope, no volume pots on the CDP. It does however have digital ouput, so I could use it as a transport, and get an outboard DAC that had less, or adjutable output. Also since the amp can work both as an intergrated and power amp I could just simply hook up my PS Audio IV passive preamp to it. Honestly this has been the only CD so far that has driven it into distortion. The Mullards are funny tubes too. They "flash" when powered up. Really kinda strange to see. I might just roll them out to see if another tube doesn't distort as easily.
  • 11-16-2010, 07:35 AM
    Geoffcin
    Quote:

    Originally Posted by TheHills44060
    Are you using the 4 or 8 ohm taps on the amp?

    I'm using the 4 ohm taps.
  • 11-21-2010, 11:12 AM
    Geoffcin
    Quote:

    Originally Posted by Mr Peabody
    I'm not familiar with that brand. How is it an improvement over your current one? Getting new gear is always fun, congrads.

    Sorry to take so long to write this down, but if you want to get past the "first impression" bias then you gotta give it some time.

    The MC84-AB is significantly more powerful than my old MC368-B90. While only rated at a nominal 5w greater output at 75wpc, it can easily surpass the old amps output by at least 5dB with my speakers without running out of steam. This means ~95dB is my limiting SPL now.

    More focused presentation. The old amp was remarkable in it's ability to throw a huge 3d sound field, but the new amp has significantly better focus. Separating lead vocals and pulling lead instruments from the mix seem better defined. The old amp did a great job of "back lighting" leads, but this amp has a greater focus.

    Blackness. While some might call it a "darker" amp, I would disagree. This amp has one of the quietest noise floor of any amp I've owned SS or tubed. Music seems to rise up out of pitch darkness. It can be quite startling at times. I've made my wife jump out of her seat a few times already!

    This amp is not "lush" by any stretch. In some ways it's more SS like than the my old tube amp. The bass is much tighter and displays none of the "loose" quality some people would associate with a tube amp. There's significant "air", but I would say that the older amp with the KT88's had further HF extension than this one. That being said, the balance on this amp is better. I would say it's nearly as flat as a quality SS amp with my speakers, maybe even less than the + 0 db / - 2db it's rated at.

    The real proof is in the using though. I woke up @ 2am this morning with the amp running, and just a drop of Napa cab left in my glass. I had meant to listen to just a few more tracks but obviously went too far. Life could be worse!
  • 11-21-2010, 11:27 AM
    Ajani
    Quote:

    Originally Posted by Geoffcin
    Sorry to take so long to write this down, but if you want to get past the "first impression" bias then you gotta give it some time.

    The MC84-AB is significantly more powerful than my old MC368-B90. While only rated at a nominal 5w greater output at 75wpc, it can easily surpass the old amps output by at least 5dB with my speakers without running out of steam. This means ~95dB is my limiting SPL now.

    More focused presentation. The old amp was remarkable in it's ability to throw a huge 3d sound field, but the new amp has significantly better focus. Separating lead vocals and pulling lead instruments from the mix seem better defined. The old amp did a great job of "back lighting" leads, but this amp has a greater focus.

    Blackness. While some might call it a "darker" amp, I would disagree. This amp has one of the quietest noise floor of any amp I've owned SS or tubed. Music seems to rise up out of pitch darkness. It can be quite startling at times. I've made my wife jump out of her seat a few times already!

    This amp is not "lush" by any stretch. In some ways it's more SS like than the my old tube amp. The bass is much tighter and displays none of the "loose" quality some people would associate with a tube amp. There's significant "air", but I would say that the older amp with the KT88's had further HF extension than this one. That being said, the balance on this amp is better. I would say it's nearly as flat as a quality SS amp with my speakers, maybe even less than the + 0 db / - 2db it's rated at.

    The real proof is in the using though. I woke up @ 2am this morning with the amp running, and just a drop of Napa cab left in my glass. I had meant to listen to just a few more tracks but obviously went too far. Life could be worse!

    I'm hoping you mean that you couldn't tear yourself away from the amp and eventually fell asleep listening, and not that the sound was so boring that you soon dozed off! :lol:

    Seriously though, congrats... Upgrading can be so much fun (especially when the upgrade meets/exceeds your expectations)...
  • 11-21-2010, 05:43 PM
    Mr Peabody
    Sounds like a very good amp, I'd like to hear it. If you don't mind saying what does one cost? I heard the Octave Audio tube amp rated a 40 watts but had the substance to drive Dynaudio C1's into a decent volume with good control. It was impressive but at $5k it needs to be. Your amp sounds very competent so I'm curious at the cost.
  • 11-21-2010, 06:22 PM
    frenchmon
    Here you go peabody...http://www.pacificvalve.us/MDMC34AB.html

    Sale price about $1500 claims