MV50 amp with Quad Speakers

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abwilson
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MV50 amp with Quad Speakers

Post by abwilson »

Hello,

Is anyone using a conrad-johnson MV50 with Quad speakers? My listening space is a basement set up, 8 foot ceilings, maybe 18 x 18 feet floor space. I listen to mostly unamplified music, small jazz groups and most releases on ECM for example. I am curious as to whether you are satisfied with the amount of power relative to the speaker. I recently acquired a pair of ESL988's and am trying to decide how much money to invest in repairs/upgrades or simply put it in working order, sell it an upgrade to a new more powerful amp.

Thanks in advance,

Alton
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Re: MV50 amp with Quad Speakers

Post by joeinid »

Try sending a PM to this user: memberlist.php?mode=viewprofile&u=558

Big Dog RJ has Quads and CJ.
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Re: MV50 amp with Quad Speakers

Post by ronenash »

I suspect you will need a higher power amp for the Quads. I used Martin Logan with Premier 12 monoblocks and LP125m monoblocks and they drove the MLs beautifully.
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Joe Appierto
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Re: MV50 amp with Quad Speakers

Post by Joe Appierto »

I would tend to agree with Ron. Not sure how similar the 988's are to the 989's but I found the latter to be relatively inefficient. I loved them and had them for over 10 years but they did tend to soak up an amplifier's output. I originally ran them with a c-j Premier 11A (rated at 70wpc but more like 50 to 60 in real life) and the sound was nothing but musical. Really nice. Then purchased a Premier 140 and the Quads were able to really open up. Sound stage was wider and deeper, better dynamics, etc.

Should you decide to keep the MV50 then you'll most likely want to have it looked over by c-j. At 25 to 30 years old, the amp will most likely need some work. Don't know what your budget would be but here's an article from http://www.tonepublications.com/old-sch ... son-mv-50/ Tone Audio where a longtime MV50 owner had them do the C1 Teflon capacitor upgrade and they also rebuilt the power supply for about $1,500. Don't know what it'd cost currently.

Don't know how the dealers are in your area but if you could get a loaner amp from them then that might be a possibility before you decide on upgrading the MV50. Just a thought.
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abwilson
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Re: MV50 amp with Quad Speakers

Post by abwilson »

Joe,

Thanks for the comments. I believe it is approximately $1125 plus shipping to do the capacitor upgrade now, and I am sure that the amp has other problems that need attention. That was the point of my question, not knowing what 40 - 50 watts would mean to the Quads. If the amp is going to be limited in power to drive the speakers, is it worth spending $1100 - $1500 and then eventually selling the amp for something more powerful. I probably will just spend the minimum to get it functioning and then sell it for something more powerful.

Regards,

Alton
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Re: MV50 amp with Quad Speakers

Post by Big Dog RJ »

Hey Alton,

Just came across this today. Did you get another amp for your Quads (ESL 988)?

Just to share my experience: been using various iterations of c-j pre & power amps since the 80's... Including several well known 400 watt monoblocks with various types of panel speakers, such as Magneplanar ribbons, and Martin Logan and Quad ESL's. Depending on the size of room, and your listening tastes, the amplification could be customed. You don't generally have to have mega watt amplification to get Quads to sing, and once the amplification is just right, boy do they sing!

The MV50 is plenty of power to drive the Quads. I was using a 300B SE Class A of just 8 watts to drive my big ESL 2905's at one point, and this was plenty in my my room (14ft wide x 10ft height x 20ft length). Again, it all depends on the level you want to listen. If it is low to moderate where you just want to relax and listen for endless hours without any fatigue whatsoever, then the MV50 will provide you plenty of that. However, if you want to blast off the roof, obviously the MV50 is not capable of that, plus Quad stats are not meant for that in the first place! Your better off with a dynamic driver type of design or a large maggie, like the MG3 or 20 series, in which case you will need powerful monoblocks to get them going. This is a totally different ball game compared to Quads.

Having said that, c-j is not about just watts. Although a healthy does of watts is good to have, it's far more important to have plenty of "current drive" in the amp. The Quad's are a "reactive load" where the impedence changes dramatically with the frequency of the signal. Quad's impedence swings are somewhere around 1to2 ohms, and then suddenly climbs to around 16to20 ohms, and then would suddenly dip again to around just 1ohm. This is absolutely fatiguing for the amp and most amps without stable "current" capability get stressed and simply shut down, causing several other damages to the panels as well.

c-j tube power amps have no problem with these impedences, because all their tube designs provide high current output and are very stable in this regard. They are capable of driving virtually any speaker with ease provided the impedence load is well matched, and all their amps are very musical. Hence, when you purchase one of their entry level models such as a 60 watter, and compare it to a 300watter, the basic musicality is the same, the main difference is the power output and its capability of driving the speakers to full potential without any strain. The bigger amps have a better grip on the bass, plus overall presence. However, soundstage and musicality are equally satisfying in either their 50watter or 300 watter. I have listened extensively to the top-of-the-line GAT and ART amps with my Quads, they sounded superb! With the current combination I have, Classic 60SE and Act2, the sound is equally superb, and I really don't see it a point to upgrade unless I was earning millions...

I think you get my point, in terms of c-j it will give you that total satisfaction regardless of what amp you're after. Obviously they cater to different budgets, so my best advise would be to go for what you can afford. c-j plus Quads is a match made in heaven; the soundstage, and presence are truly remarkable but it will not deliver earth shattering dynamics nor would it be anything close to a larger dynamic driver design.

I truly believe that Joe's GAT + ART + Sonus Faber Strads would be a treat to listen to, especially the Strads have that magical beauty in the soundstage when properly positioned. And all this magic happens because they are driven with the BEST in terms of power and finesse GAT and ART, something truly special indeed.

Anyway, I am sure that you would find the MV50 an absolute pleasure to have, and yes it is worth re-building to its original if c-j can do that for you. If you can afford better "quality" amplification then perhaps a MV60 or Classic 60 would definitely drive the Quads with more finesse. Also, one more thing if you happen to come across a Premier 11, that is another special amp to try. I have used all with Quads, and they are all superb amps made by c-j. Don't forget to partner these with very good pre-amps from c-j as well, otherwise that magic does not happen...

All the best in your findings, and do let me know how it goes. Exciting stuff indeed!
Cheers, RJ
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Re: MV50 amp with Quad Speakers

Post by abwilson »

Big Dog RJ,

Sorry to be so late with the reply, but I spent two days typing a response and then hit the wrong button and lost everything, just frustrated ... so this is a much briefer reply

But anyway, thanks for the detailed response. As way of an introduction, I have Quad 988 speakers, a completely rebuilt and upgraded Counterpoint SA5.1 preamp (however, no teflon), original Well Tempered Turntable and arm with a Benz Micro Glider, Nordost interconnects and looking for Nordost speaker cables. I only listen to jazz, mostly small groups such as Miles / Monk / Coltrane (Bluenote recordings & most things on ECM, trying to complete the 1000 series of LP releases). My listening area will eventually be my basement, once I get it finished off. The space will be approximately 20 X 15 feet X 8 feet high, with the speakers set along the 20 foot wall. I may only be able to use record shelves as the side wall boundaries. My MV-50 is out for new capacitors (Mutdorfs, no teflon$$); may consider upgrading the resistors not sure about that. I have owned the MV-50 and the Counterpoint since 1988, but there have been several periods when I have not listened to them for up to two years.

Do you think there is enough of a difference between the MV-50 and a Premier 11A to justify a $1500 - $2000 upgrade cost? I am assuming that I sell the MV-50 for $1500 - $2000, buy a 11A for $1500 - $2000 and spend around $1500 for new caps etc. I just read somewhere that the transformers in the 11A were much better, since it was a Premier-class product.

Happy listening,

-- Alton
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Re: MV50 amp with Quad Speakers

Post by Big Dog RJ »

Hey Alton,
Good to hear from you.

Well this seems like you have a few options, here is my best advice based on my experience:

1. If you are focused on a particular budget, then just keep the mv50 and do the basic upgrades required to get the mv50 back to its original condition as close as possible. CJ can easily do this.

2. Upgrading to Teflon caps is not a big deal unless your preamp was also of the same caliber or higher. The mv50 in its original state is a wonderful sounding amp with Quads. I used the mv50 with a pv12 and Quad esl63, then later upgraded to a premier11A with a solid state cj PFR preamp. I kept the premier11 for as long as I could only upgrading the preamp further to a premier 16LS and then eventually onto the Act2. In my experience it is the preamp that captures that front end first and launches it onto the power amp. Once the power amp is good enough the preamp can just cruise along with finesse and do its thing. That's when you've reached that magical synergy with cj gear.

3. If you have the chance of acquiring a premier11, that would be fine but to upgrade a premier11 would be an added expense. If it's in its original working condition and has been carefully used then this should be good enough for a fine amplifier.

4. Lets say that you do acquire a premier11 and the upgrade was done. You will not get the best out of a premier11 unless you were to partner it with a c-j premier preamp or at least something else of equal high quality and transparency.

5. I think your counter point preamp is ok for now... I would aim towards upgrading that preamp in the long run to either a premier standard cj pre or even a pv12, pv15 or classic pre would be fine.

6. Once you've got your preamp sorted out, then perhaps a premier11 would be fantastic. I would just keep the mv50 for now and rebuild towards its original condition.

The mv50 is a very special sounding instrument, partnered with the right cj preamp of high quality will deliver a factor of musicality that is truly special with Quads. As and when have the means of upgrading down the line, you will begin to realize that the huge extra expenses of top-of-the-line gear is probably not justified because the overall quality is only marginal. It is this marginal factor that we pay so much for and think we've made it, only to find something else that betters it still. Then the question us asked, why the hec did I upgrade in the first place? Hence, my philosophy, good enough is as good enough!

Cheers mate and let me know your thoughts.
RJ
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