BHK Beta Tester Reports

Let’s start fresh with a new topic specific to Beta Testers. The section is where BHK Signature 300 and Signature 250 Beta Testers post their comments. We want this to be open for public view as well as commenting from readers. I have emailed the beta group a set of questions as well as a demo CD we assembled for them to evaluate and comment on, in comparison to what they currently listen to.

If you wish to learn more about the amps or their designs, go here, and read the details, watch the many videos explaining it in detail.

Problems found by the beta testers will be fully addressed in production releases of the BHK 300 monos and 250 stereos where applicable. Not all concerns are going to be handled, like adding handles, something out of our ability to do. But when it’s something we can fix, it will be done and I’ll comment to that effect.

Have fun and let’s hope we all learn.

To have everything in one place I’m copying my posts from the BHK Arrived thread (I have the BHK 250 stereo unit):


Got mine set up after work today. A couple minor glitches. First, it took me a couple minutes to realize that I needed to loosen the binding posts to insert my banana plugs and that they then lock down on the plugs when tightened. Very nice. A manual that explains these things for idiots like me would also be nice. When the unit first started, the logo on front blinked for a while and then sound came out. Again, it would be good to have a manual to tell me that’s normal. The unit then tripped off after about 30 seconds of play, with the logo light flashing rapidly. I don’t think that’s supposed to happen. I restarted and two hours later no problems.

The sound is certainly a big step up from the Classic 250, itself still a great sounding amp after 13 years or so. On paper they are very similar and have the same power ratings. But the BHK is cleaner, displays more details, effortlessly controls the speakers, and basically just sounds right. Top to bottom I just don’t hear anything to complain about and that is not damning with faint praise. Quite the contrary. This is a great amp and worth the (considerable) wait. Kudos and congrats to Bascom, Paul, Arnie and the whole team. More to come, eventually. Now I’m just going to listen.


One of the problems I have describing the character of the BHK (stereo only, dammit) is that, to my old and untrained ears, it just doesn’t have much character to speak of. It’s just that neutral. It’s not warm and (just a bit) fuzzy like my old all-tube VTL ST85. I’ve recently revived a late '60s vintage Fisher 400 all-tube (20 tubes in total) receiver that, at a claimed 30 watts, has shockingly more bass than my other amps (and undoubtedly a corresponding bump in its frequency spectrum). The BHK doesn’t sound transistory like some of my solid state amps (my Classic 250 doesn’t really either but nor would it be confused with a tube amp and it doesn’t sound the same as the BHK). The BHK is the closest thing I’ve heard in my system to the proverbial “straight wire with gain.” And isn’t that what the ideal amp is supposed to be? (And now Paul says the monos kill the stereo–I can only imagine (with great difficulty), and really don’t want to.)


I posted my initial impressions above at 47 & 50. I still feel much the same. The BHK250 is extremely detailed but not etched or harsh in any way. Soundstage (which is somewhat limited in my small room) is relatively deep and wide. Inspired by Paul’s interview of Bascom (pt. 4), I’m now listening to Crosby & Nash’s Another Stoney Evening. I wouldn’t mistake it for the sound of David and Graham being in the room but it’s impressively close. Another mutual favorite, Bear’s Choice (I’m particularly fond of the acoustic cuts), has never sounded so crisp and lifelike. Vocals sound wonderful.

As noted above, the unit went into protection 20-30 seconds after I first took it off standby. No idea why. I turned it off and back on (just standby–I haven’t used the rear on/off since I first turned it on) and it has been fine ever since.

Now for some additional thoughts. My system is in my signature (not yet updated for the BHK). The preamp is a balanced all-tube unit using 6H30 tubes. Power cables are PSA AC12s. Signal cables are a mish-mash of PS Audio, Kimber and XLO. Balanced from DS to Preamp to amp. Source is mostly the Direct Stream with Bridge 2 beta and (occasionally) Auralic Aries. I haven’t played any vinyl yet.

I didn’t have any problems with set-up other than throwing my back out a bit and the one time it tripped off. It sounded great out of the box. I haven’t noticed major changes as it has broken in (it probably has about 30 hours on it; it is used for audio and video and is on most of the time I am at home and not asleep). I do think it has relaxed a bit and the soundstage has opened up a bit but the basic character has been there from the beginning.

I very much enjoyed my system before but this has really brought it to a new level. I can see much further into the music and the performances, whether recorded live or in a studio. Soundstage is significantly improved relative to my Classic 250 but I keep coming back to the level of detail that is revealed. With some amps “more detailed” can mean etched and a bit harsh. (I can remember listening to one famous make amp years ago at two different dealers that sounded great, except it made my skin crawl for reasons I couldn’t really articulate.) Not so with the BHK. It doesn’t really “sound” like a tube amp or a transistor amp. It just does what it is supposed to do and just sounds right. I haven’t heard anything that sounds better to my ears, even the megabucks stuff at dealers and high-end shows (although it’s hard to compare given the other differences in the systems). I enjoy listening to my old VTL tube amp in my second system but my Classic 250 blew it away when I got it. The BHK has done the same to the Classic 250. This amp is just a sh*t load of fun to listen to. Anyone who can afford one should seriously consider getting it. Anyone who can afford even a much more expensive amp (regardless of price) should get one (or the mono blocks when they come out) and spend the money he or she saves on more music. Or a new car. I am admittedly biased but that’s based on many years happy experience with PSA products.

I’m still waiting for the demo disc that Paul referred to but the BHK has made everything I’ve sent its way sing like it’s never sung before. Simple or complex, acoustic or electric, and whatever the style, the BHK makes music like no amp I’ve owned.

Reposted from other thread:
Only 6 hours on mine so far, so my comments should be taken as such. I have no idea how long the unit was burned in at Boulder. In my case I had run the Streets for the last 6 years with an XLR interconnect (A PS Transcendent, to be precise) in SE mode using an adapter. The Streets is an SE amp, but at the time I had wanted to buy a balanced amp. So it's finally here! That's the good news, the bad news is the one half of the cable hadn't been broken in yet as there was no signal going through it, so I didn't expect much at first power-up of the BHK.

Sure enough, the BHK sounded similar to the Streets at first power up. I listen to the percussion on the various soundtrack albums. Wood blocks and Taiko drums sounded very similar. (Note: I already have a tube preamp, an Audioresearch LS 26. It took me 6 months to fully appreciate what it was delivering to me vs. the PS IVH it replaced.)

Keep in mind the Streets was very unique for its time. I bought it 31 years ago. While it had “conventional” bipolar transistor output stages and an op-amp for the input stage, the amp was one of the first to use regulated power supplies. So it sounded very musical. Albeit at only 95 wpch.

Fast forward to about 5 hours on the BHK with the Transcendent interconnect cable after my wife and I watched some TV with it and I was able to get back to listening. Whoa. What’s happening here? The best I can describe it is that the instruments are all there, just as they were with the Streets. Spatially you could reach out and touch them. Even with the Streets. But now with the BHK each instrument had added a crispness, a texture, a tangible addition to the dynamic as the attack of each note now came through with so much more clarity than it did in the Streets. It’s as if (and I’m only second guessing here, mind you) the Streets had taken that energy and smeared it into the mids, but the BHK delivered it to the speaker. So now each note came across with all this extra dynamic on it.

A great test of this is strings, so out came the 2Cellos album “Celloverse,” playing “Trooper Overture,” “Thunderstruck,” and “Mombasa.” Ohhhh yeah. I knew I had been missing something in the Streets with the dynamic response, but but the BHK is so much fun I couldn’t sit still in the chair. Finally.

More later.

Oh yeah, feet. When I put my P10 into my rack a few years back I sheared off the rubber pads from the bottom of the feet. This time when I put the BHK in I grabbed a 12" long 7/8" aluminum dowel and put it under the chassis at the rear of the unit with the dowel pointed toward the heatsinks. The BHK then rolled on the dowel nicely to the back of the rack with no struggle and no help from anyone else (as there was no room for anyone else to squeeze in.) With the dowel the rubber feet remained intact and I was then able to lift each corner of the BHK at a time to put in some Herbie’s feet at each corner, then remove the dowel.

Worked like a champ.



Source: DirectStream DAC running Bridge II beta 1.1.7 Preamp: AudioResearch LS26 tube (6H30 based). BHK beta amp. MartinLogan Spire speakers and Depthi subwoofer. Interconnects: PS Audio Transcendent XLR. Speaker cables: XLO Reference 3

I have had my unit (BHK Sig, quit laughing) for 7 full days today. It arrived safely and well packed, double boxed and snug it its custom styrofoam and wrapped in plastic with a power cord. It was tough to get out of the box as there is not place to get your fingers under the near 100 lb beast. I did manage to get it out and hooked up though. After removing it from the box I set it near its new home on the rug. Then I went to slide it and the rubber pads on the custom feet tried to come off. I suggest a straight upwards lift if you can.

I am VERY impressed with the speaker connections, although I wish they were spaced out a bit more, as I wish with most speaker spades. They are in close proximity to the XLR’s and I’d like more wiggle room. Also the rear power switch is between and below the speaker post which makes it a bear to reach around from the front and feel your way around to turn it off/on (MAIN POWER ONLY) The power switch is on the front of the unit to turn off tubes/output.

The amp is a real beauty (mine’s black) outside or on top of a rack, but when you just see the front (like in my set up) it’s just black with the (albeit cool) back-lit PSA logo. I’m certain PSA saved you a wad-o-cash not building a new glorious case, like the one for my EDGE 10.1NL ,so your wallet will thank you after you buy one for yourself!

I need to stop now and tend to some other stuff, but I’ll pick up where I left off in a bit.

My kit is listed below in the signature line…

I just wanted to get my first post in the Beta Tester section. I am still waiting the arrival of my BHK Signature 300 monoblocks. Hopefully I will be getting them this week. Apparently the monoblocks were destined to start shipping about a week after the stereo version. (Heavy sigh) My list of equipment is below in the signature line. In particular, I want to point out that my current amplifier, the Musical Fidelity NuVista 300 is also a hybrid monoblock amp of similar power. I have owed them since purchased new in 2000. This should make an interesting comparison.

I will update everyone once the new amps arrive.

Alan- Looks like you have a killer rig. I always lusted after a Nuvista amp, as well as the TriVista! Sadly my TriVista SACD player turned out to be a $6K paperweight. I do like their (Musical Fidelity) kit though.

Some notes I took on day 1 of BHK- (one week ago today)

“It’s a fast amp, tons of detail and the cymbals are amazing”

“The bass is so much different than what I’m used to. It seems so much more defined and a little bit rounded but I think in a natural way not in a smeared way. I listened to some vinyl and some of my favorite playlist and it sounds really good”

“It has so much weight”

“The sound stage is huge”

“The bass gets better and better”

I agree about the bass sounding different from what I’m used to. At first I was a little concerned it might be a bit on the light side. Over a couple days I realized it just wasn’t over-emphasized or bloated (which apparently is what I had been used to). Last night I played a brief Bach pipe organ piece and there was no doubt. The bass was cleaner and deeper than I’ve ever heard it and plentiful the way it’s supposed to be.

woot said Alan- Looks like you have a killer rig. I always lusted after a Nuvista amp, as well as the TriVista! Sadly my TriVista SACD player turned out to be a $6K paperweight. I do like their (Musical Fidelity) kit though.
Thanks, Woot. At one point I had the matching NuVista pre-amp and CD player in the system. Over the years they have slowly been replaced. Back when it was new the CD player was considered one of the best made. I should pull it out of the basement and compare it to the PWT/DSD combo. smile

Hello Everyone,

I would like to thank Paul and the PS Audio Team for both running a beta test and seeking out feedback for their new product. As a side note, please refer to my complete list of equipment listed below for further details about my particular system. Prior to the BHK signature 250, I was using a pair Classe CA-M300 mono-blocks as well as a Krell Evolution 2250e. The Krell was my favorite amp of all time until I bought the Classe CA-M300s. The Classes were on another level in terms of transparency, dynamics, power, bass and mid-range and treble quality, and sound staging. Previous to that I’ve owned Krell S-150 Mono-blocks, a Bryston 4B-SST2, an Ayre V3 mkII, a Gamut D200 mkIII, a Naim NAP200, a Quad 909, a PS Audio HCA-2, a Bel Canto eVo2 GenII, and a Bel Canto S300 power amps.

My BHK arrived with impressive packaging. Krell and Classe make very specialized boxed as well. Neither was as thoughtful as the BHK with the extra corner protection strapped to the outside of a robust box. The manner in which the boxed opened and the interior packaging made removing the amp as easy as possible. Note: I would highly suggest once you open the box, plan where you want the amp and how you will place it there before lifting. At 83 lbs, the fewer times you lift it the better. Once placed in my BDI stand, connecting it was breeze. I use Kimber Kables exclusively including speaker cables with 1/4" WBT spades and XLR interconnect. My amp is plugged into a 20A dedicated outlet. My subwoofer and the rest of my system are connected to the same outlet. Cold, the amp sounded good. A little constipated, a little shut in but natural none the less. I let if play for a few hours, and it just kept getting better. After 10 to 15 hours it really stated to sing and I mean SING! Great sound staging, dynamics, pace, rhythm and timing, check. Well defined/taunt bass, transparent mid-range and extend/natural highs, check. I have a couple of test tracks, as most of us probably do. When I listen to Eva Cassidy ‘Live as Blues Alley’, Shelby Lynn “Just A Little Lovin’, Muddy Waters ‘Folk Singer’ and/or the When Harry Met Sally soundtrack, all the audiophile terms disappear from my head and I just listened, to the music. In my opinion, this is the best compliment one can pay to this amp! The biggest problem I have with my BHK is, it’s hard to walk away from. Last point, it does runs very warm to hot in my enclosed BDI stand.

NOW, back to the music, Kevin

So the verdict is they beat the Classe monoblocks?

Correct, as good as the Classe amps are, the BHK is much more realistic sounding,

Great, well written review. Thanks. I look forward to your continuing comments as the amp breaks in. It does take some time before it gets to its true sweet spot.

Hey Folks,

I want to Thank Paul, Scott and PS Audio for the opportunity to participate in the Beta Test. I finally put together my system below. I am anxiously waiting for the mono BHK’s to get here. At the RMAF last October I got my first Listen to the BHK Prototype and met Paul, Arnie and Bascom. What Gentlemen, answering every question with terrific enthusiasm. Arnie told me the BHK would just destroy my beloved D-150 as it did his 600 monos. I can’t wait to see if it is true.

I believe Paul said they were going to be using Magnepan 20.7’s in Munich this weekend. I await Paul’s report on the sound of the BHK with them and Hope they were able to take the BHK preamp also. It already seems that the BHK is a major success and I congratulate Bascom, Paul and Arnie on the design of a fine piece of gear.

Looking forward to the future comments till it gets here.

Let’s reserve this topic for Beta reports and specific discussion of these reports.

For general discussion of the BHK, questions, speculations, etc., please post in the BHK Arrives thread. The beta testers/early adopters are there, too.

I appreciate the distinction is a bit vague and artificial. But this thread is intended to be for beta testers, with review and comment by us mere peons - not a BHK free for all. For that, please go to the BHK Arrives thread where all BHK is fair game.

So the BHK REALLY opened up tonight. This is day 10, 7 days of 24/7 w/music playing, 3 days of 12 hours of music. I’ve been “squinting my ears” since yesterday when I received the PSA beta sampler disc, trying to evaluate. I had listened plenty hard before too, when time allowed. Tonight the BHK sound is WAAAAY better. I’ve taken a lot of notes tonight, and they are all about the new great sound abounding from the BHK. It will be very interesting to put the EDGE back in in a few days. I’m really starting to hear what the BHK is about.4_gif

Now to the next 200 hours. I wonder if the same 400-hour rule applies here.

woot said So the BHK REALLY opened up tonight.
Woot, you are really certain there was a sudden, significant, incremental change? I can rationalize a slow, steady settling in of some components.

(Please note I am not starting a discussion of break-in, we can do this elsewhere if someone would like to start a thread. Instead, I am specifically interested in the beta testers’ experience of burn-in with the BHK.)

It has always sounded really good, but yesterday it got meat on its bones in a very noticeable way. My wife who had been saying it was lacking in mids noticed too, saying its sounds really really good. She had not been liking the BHK and was jonesing for me to put the EDGE back in. Last night she was loving the sound, the added weight and musicality. My ears agree.

I also noted more depth and air. Effortless is how I described the track Take Me by the Cowboy Junkies on SACD. From Elton John, Love Song on SACD I noted how noticeable and defined the harmony’s were. From Terry Evans Puttin’ It Down SACD, the song Rooftop Tomcat I wrote how Terry’s voice floated (not as in moving around, but with so much presence and air), the greatness of instrument separation, and the air around the drums. Right at this moment I’m noting how the guitar sounds so well defined on Pink Floyds’ Another Brick in the Wall, Pt. 2 sounds on Echoes: The Best of Pink Floyd. The bass drum is divine, and the organ stands out and really sounds, well, like an organ!clapping_gif