Can a BHK250 owner be happy with the M1200s? My Review

As a preface, l hope this long and wordy post will help address questions of differences between two of PS Audio’s top tier amplifiers.

A recent problem required my BHK250 to be returned to PSA for repair. I had tired of wrestling with the BHK’s weight and bulkiness and was looking at lighter, more energy efficient alternatives. I decided to try the M1200 mono amps while the BHK was being repaired.

A limitation of component reviews is that components don’t function as singular entities, they are evaluated in a system context and system interactions alter the way a component sounds to greater or lesser degrees. As I am not a professional reviewer, my review will be somewhat limited in that I didn’t use the PSA amps with multiple speakers. My system is comprised of Tidal Piano Cera speakers, PS Audio BHK preamp ( I also used a DeHavilland UltraVerve,) PSA Stellar P3 conditioner for the front end, Luxman D-08u sacd player, Acoustic Signature Final Tool turntable with AudioMods tonearm, Transfiguration Axia S cartridge, RCM Sensor phono stage, two REL SHO/3 subwoofers, and a variety of cables and footers (details to follow.)

As Stu McCreary noted in his Positive-Feedback review, I also noted a depressed upper bass/lower midrange during initial listening. This “scooped” tonal character largely disappeared after the initial 150 hours. However, even after that largely resolved, the amps still exaggerated harsh overtones of certain instruments and voices and caused listening fatigue. After around 250 hours, I was about ready to throw in the towel and return the amps when further changes in the amplifier’s sound occurred. The change was so dramatic I questioned my hearing and initially wondered if I was just becoming acclimatized to the different sound. Returning to listen to my second system reestablished a familiar baseline that assured me the changes in the sound of M1200s were real. Recordings I previously couldn’t stand to listen to for more than a few minutes were no longer nearly as grating and harsh. Still, compared to the BHK250, the M1200s were more forward sounding and prone to causing long term listening fatigue with less than perfect recordings. Much experimentation with interconnects, power cords, speaker cables, and footers eventually resolved those issues.

As I listened during the break in period, I listened for the minor deficiencies in upper piano register reproduction that Michael Fremer noted in his Stereophile review. As Fremer’s Wilson Alex speakers cost four times what my Tidal speakers cost, I’m sure there are some differences in resolution. That said, I only heard a hint of the “parasitic halo” he mentioned when the piano’s upper register was played forcefully. The stock Psavane tubes seemed responsible because I never heard that again after replacing them. I generally agree with Fremer’s evaluation with one exception. His “C” grade for micro-dynamic delicacy isn’t the case in my system after all the system tuning I did with cables and footers. After system tuning, I find the M1200s only slightly less resolving of micro-details than the $30,000 or more amplifiers I’ve listened to.

Initially, I felt the M1200s were less resolving than my BHK250. I realized I wasn’t making an apples to apples comparison because I used Stillpoints SS feet under the BHK and I hadn’t done that with the M1200s. Once the Stillpoints were inserted under the M1200s, they increased low level resolution and provided all the other benefits one expects from them. Stillpoints usually shift tonal balance towards the treble along with the other increases in performance parameters. Turning the small rotating ends of the Stillpoints down instead of up corrected that shift with the M1200s. After six weeks of daily use and finding the right ancillaries, I find the M1200s at least as, if not more resolving than the BHK250, albeit with a bit different character.

The M1200 is definitely more revealing of changes in downstream components, tubes, and cabling than the BHK. After trying a number of tubes, 1960’s Raytheon black plate 12au7s are sounding perfectly balanced. Cardas Golden Presence speaker cables sounded too bright and Western Electric 10gauge was too soft, syrupy, and lacked tonal sophistication. Furutech Fa-As22 was a perfect link between the BHK and the M1200s. While they were too smooth and laid back linking the BHK preamp and BHK250, they went a very long way towards taming the over exuberant treble of the M1200.

At that point the M1200s were really closing the gap with the listening pleasure I experienced with the BHK250. They still lacked that last bit of relaxed character that made long term listening to the BHK so pleasurable. Seeing that Furutech speaker cable and interconnects proved to be so compatible, I ordered a pair of used Furutech Piezo Powerflux cables from UsedCable.com. With all Furutech cabling in place, the M1200s shed every bit of the treble exaggeration I and other reviewers heard. While some might question the value and wisdom of pairing power cables that retailed for 90% of the cost of the amplifiers, they definitely elevated the amps to a much higher performance plane. While the previous PS Audio AC12s were excellent providing power to the M1200s, the Furutech cables were on a higher level of tonal sophistication.

One spends similar money for the BHK250 and the M1200s and one might rightly ask which is the better amplification? Each has its strong points.

There is a difference in listening perspective. The BHK has a more distant rendering of a recording’s soundscape. The M1200’s are more immediate with a closer perspective. The usual reviewer’s trope of “moving several rows closer in the auditorium” applies here.

The M1200s have greater macro-dynamic expression and better bass reproduction and authority with my speakers. The M1200s are the first amplification I have heard with my Tidal speakers that produced sufficient bass to even consider forgoing the use of subwoofers.

The M1200s render recording micro-details with greater accuracy of instrumental timbre differentiation than the BHK does. The BHK reproduces those same passages in an equally satisfying but less surgically revealing manner.

The BHK ranks a little higher if one values a relaxed and “musical” presentation as a primary attribute. The M1200s allow more insight into the particulars of how a recording was made. Differences in recording technology and venue are more apparent.

In the end I think it’s debatable as to which is the “better” amp. I suspect the BHK250 is much easier to drop into a greater variety of systems without much tweaking and immediately achieve owner satisfaction. The M1200s strike me as needing much more tweaking and tuning to hit the perfect sonic sweet spot.

In my case, I’m keeping the M1200s and moving on from the BHK250.

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Thanks for taking the time to detail your impressions. It was informative and allowed me to further consider what to look for when I eventually upgrade from my M700’s.

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Wow Photon48…
Great depth in your comparison between the M1200s and the BHK 250…
Should be a big help to those considering which way to go.

As your M1200s acquire more time in use…the relaxed nature may come along.

Thanks for your carefully crafted and worded description…

Best wishes

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Great information! I own a tweaked pair of M1200’s with Gold Lion tubes, Herbie RX9 tube stabilization, Isoacoustic Orea’s, etc…… I’ve also wondered how different the sound would be with BHK 300’s instead of M1200’s. I recently heard a pair of extremely good if not great class D amps. I also heard the the difference between the companies class A/B amplifiers on the same system. What I heard was more natural sounding musical instruments, a piano sounded good on the class D the piano sounded like a real piano with the A/B. The A/B had better sustain in the transients.
Focusing on the M1200’s the limitless headroom is so good. You can listen to anything at lower levels and you miss nothing the details are always there! I’d love to hear the two side by side. I’m sure I would love the BHK 300’s but would I feel its a substantial upgrade over the M1200’s? That’s what I fear.

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Thank you for your detailed evaluation on M1200. I went with M1200 instead of BHK 250 based on Beta reviews. I need amps that can drive my big speakers better. I also like the fact that they are more efficient and lighter than my previous BAT 150 monoblocks (a lot of heat!) which costed quite a bit more.

I have not missed BAT at all. M1200, with the right cable pairing, just sounds more neutral, fuller, and more details in all frequencies. It lacks a bit on the depth and width in comparison, but it has more power and faster pace that I really enjoy.

For the price they are hard to beat!

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For an interesting perspective on the merits of the icePower AS1200 module technology used in the M1200s, read Doug Schroeder’s review in Dagogo.com about Legacy Audio’s new i.V4 amp. I have found Doug’s reviews to generally reflect my tastes in equipment. His views on Class D technology definitely challenges traditional assumptions.

(Legacy Audio i.V4 Ultra multi-channel amplifier Review - Dagogo)

Great review and comparison of the two amps.

Was wondering what tweaks if any you applied to the BHK 250? I love the sound of my BHK 250 even with the stock tubes, but when I installed a pair of Amperex 6922’s, the performance of this amplifier was taken to a whole new level. The imaging became more pinpoint, along with a wider and deeper soundstage, creating a more accurate representation of the original venue.
The music also became more alive with the presents of new found micro details and decay.
Additionally there was an increase in tonal accuracy and texture, which further helped to suspend my disbelief, and invoke a deeper emotional response to the music.

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Thats a very good point! Is the BHK using the stock tubes? if not what tweaks have been performed to the BHK 250 prior to putting the M1200’s in the system?

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Good Questions.

As to tweaks I applied directly to the BHK, I’ve used Stillpoints SS and Boston Audio Tuneblocks for footers. Multiple power power cables; Mojo Audio 9 gauge copper ribbon , PS Audio AC-12, DH Labs Red Wave, Harmonic Technology AC-11, Shunyata Black Mamba CX, Several Furutech cords, Wireworld Eclipse 5.2 with upgraded connectors, and others I’m sure. I used Mad Scientist Black Discus on the positive speaker output connectors.

As to the different tubes I used in the BHK, it would be hard to enumerate all of them. I’ve been collecting the 6dj8/6922 family of tubes all my life and I probably tried most of the usual suspects except for CCAs. My favorites were probably a pair of Telefunken 7dj8s or Raytheon 7308s.

In my system, Amperex 6922s were too bright, not pleasant. This impression was after Stillpoints SS were installed. Stillpoints tend to spotlight the treble anyway and the Amperex 6922s were too much of a good thing. While the Telefunken tubes were lively, they managed to avoid sounding excessively so.

The Stillpoints SS made the largest improvement of any tweak to the BHK in my opinion.

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Nice and thoughtful review, OP. That you are sticking with the m1200 instead of the BHK is quite telling and interesting. Impressive that you really stuck with the tweaking to get the best from it. Well done

Thank you @Photon46

very appreciate your review, also as a result of a lot of tweaks.

You are encouraging me to keep my M1200s (before going to BHK300s) and try to upgrade my 2 P12 to 2 P15s Power Plants. A question of shelf spaces obliges me to be selective, big amps or big regenerators, tertium non datur!

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Aural memory is a tricky thing, IME.

Really appreciate you sharing your experience but, if you have the time and inclination, you might consider popping the BHK 250 back in the system for a few days.

It has been my experience that one more round of comparison is needed to affirm ones preferences. I have a hunch that if you put the '250 back in you will either immediately confirm your preference or get the sense that further listening might be needed.

For what its worth and thank you again for your thoughtful post.

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Yes scotte1, you are quite correct about the ephemerality of aural memory. That was in my mind constantly for the last six weeks. I have no doubt that the accuracy of one’s memory starts to fade after only a few days. I think some of my most reliable aural memory tools are things like remembering how various sections of the orchestra dominate or recede in a recording. Also, how well instrumental timbre is resolved. What parts of snare drum, tympani, or tabla’s percussive sound are dominant or recessive? Can you easily differentiate between the oboes and clarinets in the wind section? I can remember those sorts of things well. Another more subjective aspect of aural memory is how well various recordings pass what one reviewer (10 Audio) calls the “Zen Test.” Thats how readily one can forget about the electro-mechanical aspects of music reproduction and just relax into the listening experience. That’s another part of the listening experience I think many of us can remember well.

You are correct that it would be ideal to have the BHK on hand to make comparisons that confirm preferences. I feel confident in saying that my “perfect” amplifier would combine elements of both the BHK and M1200. As I mentioned at the beginning of my original post, I am really tired of dealing with the 82 lbs. the BHK weighs. I’m almost 70 years old and while I can manage it for now that won’t be the case at some point in the future. Product form factor is becoming a more important aspect of ownership.

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Roger that!

Cheers.

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Excellent thank you!

Thanks for sharing the details of what you did and the results you heard. My speakers are an upgraded pair of Genesis 500’s with the newer servo (plate) amps and drivers as found in the current Maestros. So, yes, my speakers have onboard amplification for the bass. I have the BHK preamp feeding an Audio Research Ref 75 (original, not the SE). I took out my trusted AR Ref 5 SE in order to audition the BHK preamp. So far, wow! So much wow that I’ve got the PerfectWave DAC coming (to audition in place of my Auralic Altair) and also the latest SACD transport, the PST. I have the Stellar phono preamp in place to handle my 2 Thorens turntables. The TD-125LB has a Jelco TK-850L arm and this one is my moving coil source. The TD-520 has the Jelco SA-750L arm and it handles my moving magnet cartridges, even my 78’s with an Ortofon 2M78. I use the Easy VTA adapter on both arms. So, why am writing all of this?

I want to try a PS Audio amp in this chain. I’ve considered the Stellar 300 and the BHK 250 for a stereo amp along with the mono amps: Stellar 700, Stellar 1200, or BHK 300. I already tried out a Genesis GR360 and it really worked with my speakers but it was defective, so back it went to TMR.

With my low bass handled already by the speakers themselves, I think that either BHK 250 or 300 would be superb. But the 1200’s are all the more interesting after reading the OP’s writings. I wonder if the Stellar 300 stereo amp would serve, seeing as I need not provide the power for the lowest frequencies, thanks to my Genesis servo amps?

One thing I’d wonder about is whether the older technology icePower modules in the Stellar 300 and 700 puts them at comparative disadvantage vis-á-vis the AS1200. Plus, the tube input stage definitely adds more to the package in terms of being able to fine tune the final result relative to the other Stellar amps. It is pretty amazing how much influence different tubes have on the M1200’s sound, more so than I found to be the case with the BHK250.

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The tube input stage is the sweet spot with the M1200’s over the other Stellar amps! The extra headroom and wattage doesn’t hurt either!

Having owned mono’s with those older ICE modules and even a 1200AS based amp without the tube input stage I will tell you that the BHK 250 is a different animal altogether. If the size and weight of the 250 don’t bother you then that is the sweet spot in the PSA amp lineup to me. I turned 67 a couple of weeks ago and while I can still handle the weight of the 250 the day is coming that I can’t or don’t want to. I have two amps that I swap in and out of the main system and instead of putting them in the rack on the bottom shelf I bought two amp stands from Butcher Block Acoustics with threaded inserts and place the amps in front of the rack. Instead of spikes I use Herbie’s threaded gliders so when I want to swap amps I just slide one out of the way and replace it with the other. That way I don’t have to man handle the 250 until I move or sell it. I put the P3 on the bottom shelf so that all of the PC’s come straight down and the one for the amp goes under the rack and up to the P3.

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Your Genesis 500s are going to appreciate a tube front end in my opinion. I’d opt for VTL S-200 or a conrad-johnson Art 150. Should you prefer solid state Pass 250.8 would be my first choice. The Audio Research are fine amps but may be a little to forward and bleached out compared to a cj, Vtl or Pass. The PS Audio BHK 300 is a contender as well, but I’d opt for a cj for those particular speakers.

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