TAS Review of BHK300

I got the digital version yesterday. A rave review from Tony Cordesman. He’s keeping his current amps but buying the review pair for a second reference system he is assembling.

Congrats to Bascom, Paul, Arnie, Bob and the whole PSA team!

Is this available online?

stevem2 said I got the digital version yesterday. A rave review from Tony Cordesman. He's keeping his current amps but buying the review pair for a second reference system he is assembling.

Congrats to Bascom, Paul, Arnie, Bob and the whole PSA team!


Thanks Steve!

+1 on the congrats, and WOW!

Thanks for the heads up. Just renewed my subscription just for this review :)

Mark A. Larsen said Is this available online?
Typically new reviews in the current issue are not immediately available on their website, but they're usually posted a month or two later.

Right. I subscribe to both the digital and print versions (they’re both cheap) and sometimes the digital arrives well before the print, and sometimes it doesn’t.

Thanks. I just purchased a TAS digital subscription and skimmed though the review. Congratulations on a stunning review.

A couple quotes:

"You do, however, get your money’s worth with the BHK Signature 300s. They have truly exceptional imaging, depth, and natural soundstage width, and they really can get the best out of the naturally miked and produced recordings that have a real- world soundstage. Once they are broken in, they have very little sound character of their own, but to the extent they do, they have a rich, natural musical timbre without any loss of highs or air. "The 300s’ dynamics are extraordinary, particularly in the lower octaves that seem to be in even more demand for audio reproduction today than the upper octaves (higher levels) that had previously been the key design challenge—until great performance at high powers became the rule, rather than the exception. Bass goes as deep as your speakers will permit. The amp’s control with difficult speaker loads is excellent, while the upper bass and lower midrange—which dominate most actual musical sound—have no touch of leanness or lack of natural warmth.

"Summing Up

"A truly excellent amplifier. Scarcely cheap, but less expensive than most of the amps that challenge it in quality—and the ste- reo version is half the price of the monoblocks. I’m not giving up the Pass Labs 160.8s, but I am putting a second reference system together, and I’m keeping the BHK Signature 300s. Two of the best power ampli ers around can be better than one."

In the same issue Steven Stone gives a great review to the PSA NuWave DSD DAC, but that’s another thread (and I haven’t read the whole thing yet). It’s a big double win for PSA.

I just finished a closer read of the review. This is as good as it gets.

PS Audio should be very pleased with the review and the comparison to the Pass Labs XA160.8, reviewed in the same issue. I think the reviewers are having difficulty deciding which of the monoblocks they liked more. Anthony H. Cordesman obviously could not pick one over the other. I would think that most buyers will notice the weight and price differences, and my guess is that the Pass Labs will heat a room faster and hotter than most fireplaces.

Yes, rarefied air.

Congrats to you both, Paul and Bascom. This is great news!

Mark A. Larsen said I just finished a closer read of the review. This is as good as it gets.

PS Audio should be very pleased with the review and the comparison to the Pass Labs XA160.8, reviewed in the same issue. I think the reviewers are having difficulty deciding which of the monoblocks they liked more. Anthony H. Cordesman obviously could not pick one over the other. I would think that most buyers will notice the weight and price differences, and my guess is that the Pass Labs will heat a room faster and hotter than most fireplaces.


Thanks guys!

Great review!

All you have to do is listen.

Congratulations to all, especially Bascom King, who must again! feel great about his new design! Love these amps. I’m THERE!

Thanks guys!!smiley-music005_gifmusic-078_gifdancing-009_gifinlove_gifhappy-132_gif

Here is the full review.

http://www.whatmoughaudio.com.au/wp-content/uploads/2015/12/Absolute-Sound-Review-Jan-2016-BHK-Monos-final.pdf

Yes, I am back from the dead. Have been extremely busy, with little time to listen and post. Quick update on my amps. They are really singing now. Initially I used them with Spectral preamp and MIT cabling, with very poor results. Taking out Spectral improved things a bit but still left me unsatisified. Swapping out the MIT cabling for Transparent Reference made all the difference. They sound great now. I was truly shocked about the difference the cabling made.

A mouth-watering review! I’m really looking forward to an audition–will you be showing it at the Newport Show in June?

I’m curious about the circuit after watching BHK’s video talk with the sketch: is this a quasi-complementary circuit, related to the great quasi-comp circuits of the early days of solid-state amps, such as the Quad 303, the Citation 12, and some of the early Scott transistor amps? I’m pretty sure the early Naim Naits were quasi-comp also.

I have always loved the sound of those amps (I still use a 303 in my small study system), and I’ve read opinions from a number of people who seem to think that the NPN quasi-comp circuits were largely responsible for their warm and organic sound; also their low noise. I’m curious whether the BHK is a lineal or lateral descendant of those classic circuits…

Thanks for any insight! Kevin

I hope Bascom will chime in. I know it took him years to refine the circuitry down and understand the musicality of the single N device type that helps this amplifier be so musical. It really does suggest full complimentary circuitry, for whatever reason, has some measure of coldness to its sound - and the BHK fixes that in spades. The most musical sounding amplifier I have even had the privilege of listening to.

We were not planning on attending Newport.

kevingan said A mouth-watering review! I'm really looking forward to an audition--will you be showing it at the Newport Show in June?

I’m curious about the circuit after watching BHK’s video talk with the sketch: is this a quasi-complementary circuit, related to the great quasi-comp circuits of the early days of solid-state amps, such as the Quad 303, the Citation 12, and some of the early Scott transistor amps? I’m pretty sure the early Naim Naits were quasi-comp also.

I have always loved the sound of those amps (I still use a 303 in my small study system), and I’ve read opinions from a number of people who seem to think that the NPN quasi-comp circuits were largely responsible for their warm and organic sound; also their low noise. I’m curious whether the BHK is a lineal or lateral descendant of those classic circuits…

Thanks for any insight! Kevin

Hi Kevin. I agree that some of those quasi-comp circuits did sound good. I designed an integrated amp for Marantz, the model 1120 that was the only quasi-comp amp they made. I still listen to the prototype of that unit in my lab in the form of a separate preamp and power amplifier. So, to the new BHK output stage. No, it has no relation at all to a quasi-comp circuit. Those circuits are basically Darlington output emitter followers with the lower NPN output device put in a compound gain of 1 feedback loop to make it look like a PNP output device to try to match the upper NPN emitter follower. The new BHK circuit uses same sex N channel MOSFET output devices because they are better than the P channel output MOSFETs. Further, they are operated as common source amplifiers. They are driven with a P channel MOSFET differential amplifier that provides symmetrical current drive into the gate to source resistors of each of the two output devices. Of course those "two output devices" each have three more matched devices in parallel for appropriate current capacity. The circuit is so symmetrical that if one slowly reduces the AC voltage to the amp, the output waveform remains symmetrical down to when it finally dies out.