CONRAD JOHNSON MV50 Owners, anyone outthere?


Hi
I have one of these old babys in my main system and I love the way it sound.
The sweet,warm and relax sound it delivers.
Year after year I refuse to sell it and buy another tube amplifier, although all my friends said that im crazy and this guy belong to the past.
So, last night, I was wondering how many people outthere use it today in his main stereo system?
And also if anybody has made some capacitors and other type of upgrade like the ones that partsconexxtion offers?
Well, lets see how many MV50s are living and kicking today...
128x128alanbrain
I got an MV-55 that even thought it doesn't get much use lately,it still is a keeper for rotation purposes.Great little amp .
I used to enjoy MV50 (plus PVxx pre-amp) for a couple of years, it was mainly for my Roger 3/5A. Changed to transistor amps afterwards (sold it away due to lack of spare room).

Yes, still remeber (and miss)the sound of that. a good match for 3/5a, specially for vocal music.
Cheers
I owned an MV50 many years ago. Ran it with Rodgers LS3/5A's and Vandersteen 2Ci's. Their used to be an upgrade by the facory, to an MV52 which entails replacing the power supply capacitors will all polypropylene capacitors. I wouldn't be surprised if the factory still offers this. Maybe you could talk them into replacing the fixed power cord with a socket that would allow for an after market cord.
Alan,

I had my MV45 since the mid '80s, driving a pair of Quads 57 with a PV6 as the line stage. I totally agree with you regarding its good sound. I guess it has something to do with the EL34's. Last year, I bought a pair of Quad 988s and felt the MV45 a little underpowered. So against all advices, I bought a Premier 140. My friends predicted that I would have to re-mylar my speakers in no time. But as it turned out, the 140 is quite a good match given the inefficiency of the Quads. The 140 is not as warm and sweet as the MV45, but just by a tiny bit. Its probably due to the 6550 output tubes it uses, its more open, dynamic and authorative. Overall, I think it sound much better than the MV45 and I highly recommend to look into the Premier 140.
I have heard the Premier 11 in a store a couple of times and it is quite a bit more open and dynamic than the MV45 was at my house.
Alan, I was trying to improve its sound for you. I do not own one. I now see you'll be replacing it so improving it is a mute point.

But I have to ask...if you love its sound so much, why replace it? Does it have enough power? If you replace it, maybe the current MV60 would be a good bet for you. It has a little (1.1dB) more power, lots better/bigger output transformers(same as in the Premier Eleven-A as I understand it), and it's LOTS better looking. Can operate in triode, too.

Your love of the basic sound of your '50 may be the result of its use of EL34 output tubes, so if you replace it, I sugggest another EL34-based amp. If you want significantly more power, that would mean at least 2 pairs of '34s per channel.
.
So, it seems that Im one of the few that still use this vintage gear in his main set up...
I really loved the way the mV50 sounds in my system, the round and sweet type of sound it provides. But I think there has to be outthere another more recent gear that has that same type of sound,,,Do you know if the Premier 11 has that same type of sound?
Thanks
I also had an MV45 about 20 years ago. Along with a PV5 purchased a year earlier, these comprised my first all tube system. Had to send the pre-amp back for repairs twice and the amp once. I then decided to go with transistors in about 1990 but lost interest in music listening. Had to go back to tubes to find myself planted in the sweet spot for any length of time. I found CJ very helpful during all three repair shippings and they even twice sent back new phono tubes with the pre.

However, I think my mid 80s experience with CJ stuff was rather typical. I also bought a PV3(4?) in 1983 which had a resistor go bad (how does that happen??) and CJ fixed it. All four times repairs were done I paid shipping to them and CJ paid for return shipping. No complaints with their customer service then. I'm sure, however, their stuff from the last 10 years is very reliable. Have heard nothing about problems.

By the way, I haven't had a tube amp/pre-amp problem with anything since going back to tubes 15 years ago. Longest time with one piece was an Air Tight amp owned for over four and one half years, it performed flawlessly and made great music.
I don't own one but have always liked it. I heard it many times with ML CLSs. It could not control the bass but still had magic.
Hi there,
I used to have a CJ MV45. I figured that a tube amp with my vintage electrostatic loudspeakers was the way to go. Ultimately I had a bad experience with my CJ equipment (both pre amp and power amp). They were very unreliable and poor quality. To make matters worse, I received rather poor support from CJ. The transformers in the MV45 buzzed significantly, and the capacitors failed (CJ initally claimed they were OK). I had to send the transformers to the manufacturer to have them reimpregnated (again no help from CJ). When I took it apart, I noted that the single-sided, hand laid PCB had an intential gouge throug a trace which I concluded was there to break a ground loop in the layout. I was happy to sell these units (nearly gave away the MV45 due to the cap replacement cost).
Ultimately I concluded that tube amps are unreliable (esp CJ) and have significantly more distortion than properly designed transistor amps.
I have checked in Internet and it says this "The MV50 was, in effect, a more refined version of the earlier MV45. The input voltage amplifier included a cathode follower to provide low impedance drive to the inverter stage, to which it was direct coupled, eliminating one capacitor from the signal path. The remaining coupling capacitors were "cjd" polystyrene. Separate discrete dc voltage regulators supplied dc voltage to the input amplifier and the phase inverter."
So, I suposse My MV50 has that caps.
But, Whats the issue with that capacitors?
Please give us some light
Thanks for the replies
Makee, Yes,I think iMV45 counts. How is the sound? What is your setup?
And "Alan, does your '50 use the great-sounding cjd 'styrene caps? 'Propylenes as main-PS caps and not 'lytics? Do you have a schematic diagram?"
I have the original manual, and I can tell you the MV50 hasnt had any modifications., The caps you are talking about were the CJs factory originals or they are an upgrade. As soon as I arrive home, I will check, I think there is a diagram in the manual.Jeffreybehr, Could you shed some light on that? , Do you have a MV50?
Alan, does your '50 use the great-sounding cjd 'styrene caps? 'Propylenes as main-PS caps and not 'lytics? Do you have a schematic diagram?
.
Just in case my set up is
CJ MV50
Sonic Frontiers SFL1(upgraded by partsconextion)
ROTEL RCD991E (as a transport)
Cal Alpha DAC (not the 24/96)
Tyler Reference Monitors
Pikes Peak speaker cable AQ dbc cable
Jaguar AQ dbc IC
Z squared IC
Black Mountain Cable digital IC
ASC tube traps
Vibrapods and Vibacones
Cable elevators
Power Cord Vh Audio
I used to have a pair of triangle celius 202 but due to room size I have changed to a pair of tylers reference monitors.
Do you own a CJMV50?
Alan