NEW !!!! conrad johnson MF-2550SE Solid State Stereo Power Amplifier

joeinid

Well-Known Member
Mar 14, 2011
1,543
12
400
NY
conrad johnson MF-2550SE Solid State Stereo Power Amplifier--Bill Conrad calls this the "best solid-state amp" cj has ever built.

Bill Conrad and Lew Johnson have put their significent talents into a new solid-state amp and this is the result. Fast, dynamic and transparent are the typical solid-state strengths that we've come to expect from cj's amps...What we didn't expect was the level of harmonic coherence, something that we always expect in cj tube amps, to be so present in this new amp. Take the stunning performance of the MF2250 and add ultrapremium parts such as Dale and Vishay resistors as well as a liberal sprinking of cj's proprietary, state-of-the-art Teflon capacitors and you have cj's best solid state amp...ever...the MF2550SE


Power:250 watts per channel RMS both channels driven into 8 ohmsfrom 20Hz to 20 kHz at no more than 1% total harmonicdistortion or intermodulation distortion.Sensitivity:2 V rms to rated powerFrequency Response:20Hz to 20 kHz +0/-.3 dBHum and Noise:100 dB below rated power outputPhase:Phase correctInput Impedance:100 kOhms


Has anyone heard this yet?



 

LL21

Well-Known Member
Dec 26, 2010
14,411
2,509
1,448
Wow...there have been some major leaps forward in their amps with GAT combining much of the magic of ART pre with the linearity and low noise floor of ACT. ART monos apparently also a major leap forward for CJ. Would love to hear this SS amp. Wonder if this amp is similarly a real step forward for CJ in SS. Are you going to try it?
 

bgiliberti

Well-Known Member
Mar 28, 2012
46
3
913
Based on CJ or McCormack

Wow...there have been some major leaps forward in their amps with GAT combining much of the magic of ART pre with the linearity and low noise floor of ACT. ART monos apparently also a major leap forward for CJ. Would love to hear this SS amp. Wonder if this amp is similarly a real step forward for CJ in SS. Are you going to try it?
I wonder if it's based on the McCormacks (sp?)?
 

joeinid

Well-Known Member
Mar 14, 2011
1,543
12
400
NY
Wow...there have been some major leaps forward in their amps with GAT combining much of the magic of ART pre with the linearity and low noise floor of ACT. ART monos apparently also a major leap forward for CJ. Would love to hear this SS amp. Wonder if this amp is similarly a real step forward for CJ in SS. Are you going to try it?

I really want to hear it and probably will get it at some point.

I wonder if it's based on the McCormacks (sp?)?

It looks like typical CJ to me. I hope someone with a Premier 350 will take a photo of the inside to compare.

Here is the new MF2550SE amp.

 

microstrip

VIP/Donor
May 30, 2010
20,806
4,698
2,790
Portugal
I really want to hear it and probably will get it at some point.



It looks like typical CJ to me. I hope someone with a Premier 350 will take a photo of the inside to compare.

Here is the new MF2550SE amp.

You still have two wishes left, master Joe.
 

Attachments

  • a1.jpg
    a1.jpg
    199.6 KB · Views: 3,363

joeinid

Well-Known Member
Mar 14, 2011
1,543
12
400
NY
There seems to be a 35-40 pound weight difference between the Premier 350 and new MF-2550SE.
 

Big Dog RJ

Well-Known Member
Feb 2, 2012
1,242
463
1,155
Melbourne
Good day mate,

This certainly is a new launch for a ss amp from c-j... but to me does not look anything new. Rather seems like a Mc-Cormack. I have owned several older iterations of their MF series amps before going to tubes. All I can think of is that this amp is not premier standard, and will not be in par with their own premier 350, which in my humble opinion was and is still their best ss amp ever made to date.

This would probably be one of the best MF series amps made so far...
Therefore, I don't think it would be fair to compare it to their prem 350.

Cheers and enjoy the music! RJ
 

Phelonious Ponk

New Member
Jun 30, 2010
8,677
23
0
I understand the use of the word "coherence" when talking about speakers, and particularly drivers relative to each other in a speaker, but can anyone explain what "harmonic coherence" means?

Tim
 

bgiliberti

Well-Known Member
Mar 28, 2012
46
3
913
Good day mate,

This certainly is a new launch for a ss amp from c-j... but to me does not look anything new. Rather seems like a Mc-Cormack. I have owned several older iterations of their MF series amps before going to tubes. All I can think of is that this amp is not premier standard, and will not be in par with their own premier 350, which in my humble opinion was and is still their best ss amp ever made to date.

This would probably be one of the best MF series amps made so far...
Therefore, I don't think it would be fair to compare it to their prem 350.

Cheers and enjoy the music! RJ
I have the MF-80, their first SS amp. Still like it a lot, and in fact prefer it to the ET-250 and the McCormack DNA 250, which I home demo-ed next to it. Sound is definitely vintage, but it is more convincing to me musically than the latter two. However, the MacCormack was a solid amp, and if CJ took off the rough edges with improved components, I can imagine that the 2250 could be quite impressive.
 

Big Dog RJ

Well-Known Member
Feb 2, 2012
1,242
463
1,155
Melbourne
Yes agree! The MF-80 was an outstanding amp for the price. Beat the hec out of many so called "high-end" amps in its hey day. Sure won't forget that sound, I had this unit driving a pair of maggies MG3.5/R's in bi-amp, with the more powerful MF2300 for the bass. Upgraded to MF2100, then MF2200, and another 2300 and finally onto tubes starting with the premier 11A, and prem 12 monoblocks. Of course this took a different turn and my love for tubes evolved.

I guess c-j would have to put out some ss amp for that range being this new MF series, but I really don't know how much this is going to cost. For one thing their will be better sound out there for that money, such as ARC, VTL, Manley, McIntosh, Pass Labs etc. This c-j thing better step up to the plate!

Cheers, and please do let us know how it sounds on whatever system it's hooked up to.
RJ
 

bgiliberti

Well-Known Member
Mar 28, 2012
46
3
913
Review of Conrad Johnson MF2550

I just bought the Conrad Johnson MF2550 (non- Teflon) and have now been listening to it for about 3 days -- I'll get to the point quickly -- it's the best power amp I've heard under $10K. As a long time CJ owner, I can attest that it has the CJ sound in every fiber and circuit. It also comes closer to the McIntosh sound than any CJ amp has ever come, which I happen to think is a plus, as I really like the powerful grip and authority that Macs bring to the table. As far as recent CJ power amps, I feel it's far better than the ET250s, which I auditioned for several weeks a while back, and found too reticent and slow -- well, maybe I just don't like tubes in my power amp, even if only on the input stage. There's been speculation that this design is based on the old MacCormack DNA 250, which I think is probably true, but that's like saying the Porsche 356 was based on the VW Beetle, which was also true, but which totally misses the real point. I had the DNA 250, and while it was a good, powerful, quick amp, it really was a great home theater amp IMHO, not satisfactory for true audiophile setups. The MF2550 has the instantaneous rise and thrust of the MacCormack's power supply, which was the brilliance of the design, without the rustic edges of the MacCormack's often sub-par parts bin. Is it really better than the PR350, as CJ implies? It's a close call, because overall, the two amps sound very much alike. But, I would say yes, because the MF2550 has 99% of the 350's feeling of effortless power, ease, and extension, but addresses what for me was the sole issue with the 350, the slight tendency to sound ever so slightly aggressive in the midrange at times. The MF2550 is super-sweet in the midrange. I would still not say it is a "tube" midrange -- it does not have the lateral expansiveness on voices that many find so engaging, but that others find too blowsy in tube power amps -- but it definitely has the CJ midrange, so intimate and palpable you could kiss Maria Callas's lips (and so real, you could feel the slap on your face if you dared try such an antic with La Divina.) So that's it for now -- this is a ravishingly beautiful power amp at a price that will put lots of people into the true high-end sound for the first time. I hope many others will give it an audition -- and a note to McIntosh fans (of which I am one also.) This is the first the CJ amp that to me sounds rather Mac-like in the way the power just grips every note and sound and keeps it under its potent control -- it reminded me a lot of the gorgeous MC452 -- so give it a whirl if you are willing to forgo the blue glow of meters for the burnished gold face of CJ. You will find what you like here too.

Current equip: Conrad Johnson Classic SE preamp (Teflon cap model); MF2550 amp replaces Conrad-Johnson MF-80 SS MOSFET; Harbeth 30.0; CD Marantz SA8004. Generic silver interconnect between amp and preamp; 12 gauge OFC copper speaker cable (nothing fancy).
 

XV-1

Well-Known Member
May 24, 2010
3,591
2,573
1,860
Sydney
Finally somebody who has heard this amp

Thanks for your thoughts on the new cj. It sounds like a great amp.

I would assume the new amp has less gain than the prem 350 and is quieter?
 

joeinid

Well-Known Member
Mar 14, 2011
1,543
12
400
NY
Thanks bgiliberti

I saw your original review on conradjohnsonowners.com

Thank you for taking the time to post. I may have to get one now, mainly because of your description and the fact it's still a CJ amp. Enjoy your new amp.
 

bgiliberti

Well-Known Member
Mar 28, 2012
46
3
913
Finally somebody who has heard this amp. Thanks for your thoughts on the new cj. It sounds like a great amp. I would assume the new amp has less gain than the prem 350 and is quieter?
The gain on the MF2550 is the same as on my CJ MF80 -- ie., normal. I never thought of the PR350 as being noisy (if you mean hum etc). I don't hear anything out of the speakers when just the power amp is on. When the tube preamp is on but no music is playing, I do pick up a little more tube rush than I did with the MF80, but it is inaudible unless you put your ear right up to the tweeter, and certainly, when music is playing, it is inaudible. I don't think the design of MF2550 is too similar to the PR350, even though they do sound quite a bit alike -- much more alike, in fact, than than the 350 and the ET250s, which was basically the same design as the 350 on the output side. So it must be more a matter of voicing, and CJ voiced this one perfectly for my tastes. FWIW, I thought the teflon MF2550SE was not as musical as the "regular" model -- too analytic and a little edgy. Probably just needed more break-in, but with it being $2000 more and me being super happy with the non-SE, I didn't feel the need to mess with it.

Thanks bgiliberti
I saw your original review on conradjohnsonowners.com
Thank you for taking the time to post. I may have to get one now, mainly because of your description and the fact it's still a CJ amp. Enjoy your new amp.
Thank you, I will be very interested in getting your expert opinion on this too, since you owned a PR350 for quite some time, IIRC.
 

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu

Steve Williams
Site Founder | Site Owner | Administrator
Ron Resnick
Site Co-Owner | Administrator
Julian (The Fixer)
Website Build | Marketing Managersing