Was the PC88/7DJ8 on the list of tubes? In my system I would describe the sound as a little more focused, tighter and detailed vs the 12AU7s. I use an active crossover in my system but only below 150Hz so comparisons would be of little use. My overall impression of the BHK is not “tubey” but more a very refined, highly musical solid state sound (my bias), especially with the 7DJ8s.
I’ll post the list of tubes when I get home tonight. I may get a few more to try once they’ve been on the tester.
I’m around 60 hours or so on the preamp. Should it be showing it’s brilliance yet or is there a performance bump yet to come?
I thought that it broke in pretty fast and did not notice changes after 48hrs or so. YMMV.
The tubes we tried were:
RCA PCC88 42LC
Phillips PCC88 42L3
POPE PCC88 7DJ8
Telefunken PCC88 DJ8 #10
Mullard ECC88 6DJ8
The Pope had great detail and the sweetest midrange but a bit loose bottom end. The Telefunken great detail and did great bass - tight, detailed and tuneful. The Mullard had a very smeared/boomy bass.
I’ll report back after some more listening.
billg said ... With the preamp, there might be a smidge less detail and just maybe just a tad more liquid vocals and "realism". Or maybe not. This is unusual for me - I usually have little trouble hearing a pretty consistent difference with a new component. There's certainly nothing lost but not really anything gained. My impressions vary slightly depending on the track. Sometimes I believe the BHK delivered a more continuous L-R soundstage and a bit of extra, but could be wishful thinking. ......Without knowing the BHK preamp:
I’ve got a hybrid preamp, like the BHK is, myself, which does make some, but not as much bloom as maybe pure tube preamps would. Instead it fairly keeps the information of the DS DAC upright. I think if in a highly resolving setup, a preamp makes close to no difference to the source, it is exceptional. The DS DAC might be one of the hardest tests for this due to it’s level of ambiance and detail.
However in case you don’t need the preamp for more headroom, dynamics or a little more body it can give or source switching, you may have the lucky situation of a perfect fit of the DAC to your power amp. In my case I need the preamp for the mentioned aspects. The DAC alone sounds more dry/sterile/thin/uncolored and less dynamic due to missing headroom.
billg said The tubes we tried were:RCA PCC88 42LC
Phillips PCC88 42L3
POPE PCC88 7DJ8
Telefunken PCC88 DJ8 #10
Mullard ECC88 6DJ8
The Pope had great detail and the sweetest midrange but a bit loose bottom end. The Telefunken great detail and did great bass - tight, detailed and tuneful. The Mullard had a very smeared/boomy bass.
I’ll report back after some more listening.
In my rare tube comparisons, the Telefunken also won, as at the end, I didn’t want to loose bass control.
Got some more listening time in and all I can say this preamp knocks it out of the park. In my previous expirimentations I found that anything below $10K was neutral at best, and the $13K ARC 5SE was the only preamp I ever used that unambigiously improved sound. The BHK does so as well at less than half the price. I have made too many systems changes to conclusively say which one offers more improvement over DAC direct (which will also be system dependent), but the improvement I was hoping to get out of resinserting a preamp in the system has been delivered. Just more musicality, more space and dymanics across the board.
I am very pleased with the BHK Pre. I am using stock tubes atm but will do some rolling once I get a good handle on its default signature (Pun intended).
longbowbbs said I am very pleased with the BHK Pre. I am using stock tubes atm but will do some rolling once I get a good handle on its default signature (Pun intended).after 400 + hrs on the stock 12AU7s I replaced them w/ a pair of Tungstram PC88/7DJ8's. I think you lose a little low end (perhaps too heavy) but gain top end detail and sparkle. Thanks to BHK and Paul to have the option.
Hello PS Audio forum regulars and occasionals!
This is my first post. As I’ve participated in the BHK Pre beta and am reviewing this unit I’m posting here in this thread, but this is really a review of the DS Jr / BHK Pre combo since both are new to me. Before getting to that, a bit of context:
The background
I’m a consumer electronics and digital media professional - much of what I spend my efforts on during the work week is improving the user experience for digital media across a range of CE devices. I have a EE degree, but I’m not a practicing engineer, and finally I’m a big music fan and self-admitted house head. While I appreciate quality music across many genres (rock, pop, folk, americana, roots country, reggae, and various forms of electronica) you’re likely to find high fidelity banging house or techno at my place on a given weekend night, which might be helpful context for the expectations I have of my audio gear.
I’ve been running Martin Logan Aeon i towers since I snagged a pair of floor models at an inventory closeout sale years ago when Tweeter shut down all their CA stores at a markdown of “A LOT” (which was actually written that way on the sale tag). I got into a tier of speakers that normally would have been well beyond my means, and since then I’ve been focusing on upgrading the gear feeding those towers as funds and time allow. Most recently I’ve been using Peachtree gear – the Grand Integrated X-1 as a DAC/Pre, and the Peachtree220 (modern ICEpower class D amp) to power the MLs. My listening environment is a small but dedicated, isolated, well treated and EQ’d room.
I’ve been seeing the stellar reviews of the Directstream DAC, but wasn’t willing to spend the $6k for it, but when the DS Junior came out recently, had the network bridge built in and was eligible for a trade-in discount, I bit the bullet and went for it. The plan was to use the DS Jr as both a DAC and Pre as all my sources are digital. I could then move my existing integrated into another room. Double upgrade. Perfect.
Directstream Junior DAC (Yale)
The first thing I noticed when I flipped the power switch on my shiny new toy was hum from my speakers. Not good. Then buggy volume & muting behavior, occasional audio dropouts & distortion, fidgety remote…it was a rough start. I was a bit dismayed but worked with PS Audio Sales and CS to resolve issues where possible and to file bugs where appropriate. In all honesty it felt like I was beta testing a product rather than unboxing a new premium piece of kit, but we worked through it. In summary, some of the issues were on my end and which I was able to resolve (like don’t upsample in software and then send that signal to an upsampling DAC), some issues other components fixed (balanced cables resolved the hum), some bugs should be resolved in the Torreys FW update (pressing DIM hopefully won’t mute the audio anymore), and some we still needed to work through – most importantly the impact on sound quality.
On one hand, the resolution and imaging was definitely better with the DS Jr. As a DAC, it was superior. On the other hand, with my set up at least, when running the DS Jr direct to my amp my system didn’t have enough "oomph" or body as when running through my pre-amp. It wasn't volume that was the issue - it could go loud, but loud and thin, with not near as much visceral impact. When I ran the DS Jr through the pre-amp stage of my integrated I got the fullness back, but I lost a lot of the imaging and clarity improvements that the direct connection provided.
This difference was not subtle. I was trying to enjoy the new kit with my wife one night. It was directly connected to the amp at this time. We were listening to Booka Shade - Black Cow off the Yaruba EP, which settles in to a massive, room filling wall of rolling bass a minute or so in. When the wave was supposed to come, and then it didn’t, I immediately paused, did a quick cable swap to put the pre-amp back in the chain, and then restarted the same track. My wife (who doesn’t geek out on this stuff as I do), immediately, without being prompted, said “Oh! Now we’re talking!”. Exactly.
Forum member RadioRadio commented earlier in this thread that he hadn’t heard a system without a pre-amp that had enough “balls”. Well I was experiencing the same phenomenon. As a DAC, the DS Junior was decidedly better than any others I previously had in my house (admittedly not a huge #) and was a major upgrade. But as a Pre, it was wholly inadequate. Maybe if you listen exclusively to violin solos or chamber music you’d be just fine, but not me. So the question was how to retain the gains in decoding accuracy and imaging, but also retain the heft and impact that was so important to me? Having had a taste of the PS Audio sound, I dipped in even further – I trusted the sw bugs would get resolved in the next DAC update and I signed up for the BHK Pre beta. In addition to the hopeful SQ improvements, I’d be able to run balanced from DAC->Pre->Amp & get back the HT bypass functionality & 12V switching the Peachtree had. The Peachtree was a brute, a force the speakers had to reckon with. Would the BHK Pre have the beauty and the brawn? Importantly, would my stereo get its balls back?
BHK Pre-amp
It might seem like an impossible demand for a piece of gear – I need you to both get out of the way, be totally transparent, yet at the same time “add in” the body that other devices that also color the sound can provide. Let’s get straight to it. The BHK Pre steps up to the task and does just that. I must admit I mostly thought of pre-amps as source switchers with volume controls as I suspect many others do. These are necessary functions, but it would seem there is only room for signal degradation (not improvement), so the goal would then be to minimize the negatives while providing this basic functionality right?. Why even have this extra component if you could handle these functions in a DAC? I can’t explain the how or why, but I don’t view it this way any more.
I was hoping for and expecting improvements in clarity (which I got), but what struck me the most was the bass. Oh man, the bass. When I added the DS Jr DAC over the Peachtree DAC I felt like the bass got a little tighter, but the effect was subtle, and any improvements in this dimension were well outweighed by…well, the lack of weight overall. With the DS Jr running through the BHK Pre, I’ve got significantly deeper, more linear, more musical bass. Before, I would find that for most of my “normal” listening, I’d keep the subs at 5/10 gain. But for dance or electronic music at louder volumes, I needed to set the subs’ gain to 6-6.5/10. And to be clear this wasn’t to over-weight the bass - this was just to get it where it needed to be. With the new PSA DAC/Pre combo the subs’ gain is set at 5/10 all the time, no matter the genre or volume level. The subs are invisible with Simon & Garfunkel and slammin with Skrillex - as it should be. As of this writing, I’ve got the subs disconnected as I’m enjoying the new found full range sound from the Martin Logan towers alone. I think I’m actually going to have to re-EQ my room, so significant has this upgrade been.
Others have and will write flowery language about the clarity and imaging, so I won’t elaborate on that aspect. The pre-amp has exceeded my expectations in this area. I’m keeping it. I’ll leave it at that and try to be helpful in other areas.
Volume control
It is worth mentioning that the sound quality is excellent at any volume level. Across many of my previous set ups, I’ve become used to needing to get the music loud for the system to really “open up”, but that doesn’t seem nearly as necessary (maybe at all?) with the BHK Pre. With my Peachtree pre, I found that to get the best sound I’d set the DS Jr DAC volume at 70-80 (instead of 100), and then I could get up into the range of the volume control on the pre where the system sounded best, but at a reasonable overall volume. With the BHK Pre, I have tested with various DAC volume settings, and found it best to leave the DAC at 100. Gain ramps nicely on the BHK Pre, and the sound doesn’t start breaking up until very high in the dial range. It’s not flawless, but it is very good. The very audible clicks at 25 & 53 and the lesser clicks with every (or every other) volume step change are unfortunate side effects. Also, as previously mentioned in this thread, switching from a HT bypassed input where the pre’s volume is locked at a high level to a different input can be downright dangerous to your speakers if you don’t remember to change the volume back down before you hit play (which you certainly won’t always remember to do).
Set up
First of all, the Perfect Wave chassis are supposed to nest, but they don’t exactly - at least mine didn’t. I think the BHK Pre looks very nice stacked on top of the DS Jr, and while their chassis are designed to nest with their little curved feet at the four corners of their undersides that should hug the top plate of the unit beneath it, no matter how I positioned them the top unit always wanted to sit at an unstable angle. The curved feet were just a little too close together across the width of the top unit. I had some “Soft Fat Dots” and was able to raise the Pre just enough to get the feet to clear, so no major issue, but something PSA should be aware of. I had no issue with input naming or any configuration. The manual was clear, though as others have mentioned I think some of the “unique aspects” of the product like the audible clicks on volume change should be referenced in the manual so people who haven’t poured through the forums will understand this is normal.
Remote Control
The remote control (RC) functions well. Having had a frustrating experience with the RC on the DS Jr, I was relieved to see that I now only needed to occasionally change digital inputs and otherwise leave the DAC alone. I do have one major gripe about the RC though – the button illumination is way too bright for dark rooms. I’ve taken a picture of the new PSA RC next to my Pioneer Elite RC in a dim room. The Pioneer RC is illuminated enough for you to see the buttons, but not so bright you can use it as a flashlight. The buttons on the Pioneer RC also only illuminate when you want them to. When I have the room light dimmed (which is typical for evening/nighttime listening), I’m actually having to avert my eyes from the RC once I’ve got my finger on the volume buttons – I’m turning it away from me or putting it face down on the couch such is the glare. The new RC did well by putting black buttons on a silver body (like new Mac laptops) which provides good contrast, and with well placed and sized buttons, that’s sufficient! Unless you are in a pitch black listening room (impossible with all the LEDs that come on gear these days), you can already see where the volume buttons are just by looking at the remote silhouette. For me, this glowstick is actually the most frustrating aspect of my new PSA gear. I’m actually trying to think of ways to coat or cover the buttons to reduce the light output – can you imagine!? Any way to defeat the self illumination feature on the remote?
Single ended vs balanced
I happen to have both balanced/XLR and singled ended/RCA cables of the exact same length, brand, and cable construction, so it allowed me to do a good test of the new PSA gear running in single-ended vs balanced mode from DAC to pre to amp without introducing other cable-related variables. The cables are DH Labs Air Matrix. As I mentioned earlier I had hum when I connected the DS Jr with RCA cables. Getting a balanced cable fixed this almost entirely – I then got only a faint “whooshing” sound from the speakers that could only be heard if you put your ear right up to the cone drivers. The electrostatic panels were absolutely silent. The RCA cables on the other hand resulted in hum audible from the listening position. A few days of debugging led me to determine this was noise coming from the DAC, not a ground loop or other components. Getting the BHK pre in the signal chain didn’t change this. Noisy with RCA. Quiet with XLR. However, now that my stereo had its balls back, I got to experience the difference in dynamics that the balanced operation provided. I was expecting a lowered noise floor, but I was really surprised by the extended dynamics more lifelike imaging I got with the balanced signal chain. This was apparent at any volume, and I’ve been so impressed that I’ll likely only consider separates that offer XLR i/o from this point forward. I’m certain that being able to move from single-ended to a fully balanced signal chain is a meaningful part of the overall sonic improvements I’m experiencing with the new setup. Also, for those that are complaining of loud clicks during volume changes, I’ve found that I only faintly hear clicks at lower volume levels when using balanced cables, yet I have very audible, much more intrusive clicks on volume changes when using the single ended cables. If you can run balanced cables on your unit and you aren’t currently doing this, I advise it.
Headphone amp
Basically, ditto Peanut Butter’s comments. To me, this is a good sounding headphone amp, but I get the hum & the clicks on volume changes, and after limited listening with a variety of genres the headphone amp section in my Peachtree integrated to me sounds better with my headphones. The BHK Pre might have slightly more finesse, but the Peachtree just makes the cans dance better. I’m guessing here, but I think the greater finesse comes from the cleaner volume control, but then the amp stage isn’t as punchy as I’d prefer. I don’t get the transformative extended bass through the headphone amp that I get through the main pre-amp section. I’m using Audeze EL-8s, and I let the amp burn in for 2 days playing through the headphones.
AC-5 Power cables (bonus?)
During my time evaluating the DAC and Pre I’m spending time on these forums, looking for others’ impressions, issues, etc, and I see that Music Direct has a 50% off sale on the AC series power cords. I’ve tried a couple different moderately priced AC cables from two different manufacturers and not noticed any sound quality differences, so I generally wasn’t big on AC cables as an upgrade, but with my newfound love of PSA gear, I thought I’d dip in a little deeper and give it a shot. As I was using almost exclusively stock cords throughout my system, I bought 6 AC-5 cables, enough for the sources, amp, subs, and power conditioner. If I’m going to be a convert, let’s give this stuff a proper shot.
But alas, I just couldn’t tell a difference after swapping in the set. Considering that I can hear changes in the sound when I make seemingly small changes to my set up like moving furniture around the room, I think I have good ears, so I’m starting to become skeptical of people that claim to hear profound differences in AC cables. The build quality of the cables is good. Intellectually, I can buy into good quality copper, tight connections, thicker gauges & shielding that come with these cables, but my ears just didn’t hear a difference. I’m considering them an investment. They should last for my lifetime, and in theory they should be better than stock cords. I got them at a (relatively) good price, so I’m keeping them, but I’m placing them (as a product category, not the AC-5s specifically) at the very low end of the audio upgrade ROI spectrum. To me, they’re like softer footers and top weights, but more expensive and bulky. I can get the theory, but profound or even audible real world differences…not so sure. Maybe I just already have clean power? I do have dedicated lines for the media room. Next time I’m tearing into the stack of gear to swap out components, I’ll put the stock cords back in and see if I notice anything different after they’ve broken in for a while, but for now I’m tired of testing.
I think I’ll just listen to music for a while.
Great review with helpful comments. Welcome to the forum! Love the comment about “testicular fortitude”.
Yes, great review! Thanks for the tips and suggestions too.
TheFlyingDutchman saidI had a similar experience fiddling with all sorts of cables, until I inserted AC-12s into my systems which made a noticable difference. I have since moved even further up the AC cable food chain. So in my experience, you really need to spend very serious cash to get results, which understandably many folks are reluctant to do. Being a "cost / value conscience" Dutchman myself, it is with very great reluctance I spend four figures on an A/C cable (while I have no such reservation buying electronics).
AC-5 Power cables (bonus?)
During my time evaluating the DAC and Pre I’m spending time on these forums, looking for others’ impressions, issues, etc, and I see that Music Direct has a 50% off sale on the AC series power cords. I’ve tried a couple different moderately priced AC cables from two different manufacturers and not noticed any sound quality differences, so I generally wasn’t big on AC cables as an upgrade, but with my newfound love of PSA gear, I thought I’d dip in a little deeper and give it a shot. As I was using almost exclusively stock cords throughout my system, I bought 6 AC-5 cables, enough for the sources, amp, subs, and power conditioner. If I’m going to be a convert, let’s give this stuff a proper shot.
But alas, I just couldn’t tell a difference after swapping in the set. Considering that I can hear changes in the sound when I make seemingly small changes to my set up like moving furniture around the room, I think I have good ears, so I’m starting to become skeptical of people that claim to hear profound differences in AC cables. The build quality of the cables is good. Intellectually, I can buy into good quality copper, tight connections, thicker gauges & shielding that come with these cables, but my ears just didn’t hear a difference. I’m considering them an investment. They should last for my lifetime, and in theory they should be better than stock cords. I got them at a (relatively) good price, so I’m keeping them, but I’m placing them (as a product category, not the AC-5s specifically) at the very low end of the audio upgrade ROI spectrum. To me, they’re like softer footers and top weights, but more expensive and bulky. I can get the theory, but profound or even audible real world differences…not so sure. Maybe I just already have clean power? I do have dedicated lines for the media room. Next time I’m tearing into the stack of gear to swap out components, I’ll put the stock cords back in and see if I notice anything different after they’ve broken in for a while, but for now I’m tired of testing.
Agree–great review. I’ve never stacked my components but I believe you are supposed to remove the feet on the top one when you stack them in order to get them to nest properly.
And welcome to the forum! Hope you stick around and keep us posted on your impressions.
Yes. You do unscrew the feet on the upper component. I had my PWT stacked on top of my DSD at one point.
I have finally completed my assessment of the BHK Preamp.
The truth is that in my system there is no improvement, it’s actually a bit worse. The soundstage shrinks a little and the sound gets veiled and “dirty”. Not fully trusting my earts, I invited two local audiophiles over to have a listen. They both have high end audio systems and are familiar with a range of top-end gear. After two lengthy sessions on different weekends the determination was clear and unanimous.
As I previously reported I did some tube rolling. These did make quite a bit of improvement on the stock tubes but in the end my system sounds better without the preamp no matter what the tubes or cables are used. I also borrowed Kimber Select 1136 balanced interconnects to make sure cables were not the issue.
It’s great to have such a useful remote. It has a couple of niggles for me (getting really picky here):
- the backlight button needs to be pressed twice to work and it needs to stay on a bit longer
- the text on the buttons is too small for my aging eyes
- there is no way to put the dac in/out of standby mode independently (unless I missed it)
- I would like a toggle for the P10 multiwave function (told you it’s picky)
I very much appreciate the opportunity be included in the beta team for this great preamp. Although I wanted (and fully expected) it to amaze and delight, this was not my experience. In my system.
Presumably a synergie issue. The preamp just does not play nice with your poweramp.
Thanks all for the kind words regarding my review.
Regarding the comments about the BHK Pre nesting on top of the DS Jr DAC, I did remove the rubber feet on the pre. With the rubber feet removed, I believe the result should be metal to metal contact with the small curved chassis protrusions on the underside of the pre sitting on the corners of the unit beneath it, hugging plastic the top plate. But no matter how I positioned it, one or two of the four corners was always on top of the plastic top plate on the unit beneath it, not beside it. It was very close to fitting, so I’d say the manufacturing tolerances were just off.
but if with this info someone from PSA has a suggestion I’m open to it. I’ll actually probably look to space the units further apart a little, as the DAC is taking on some of the heat from the pre.
billg said I very much appreciate the opportunity be included in the beta team for this great preamp. Although I wanted (and fully expected) it to amaze and delight, this was not my experience. In my system.Thanks for your verdict.
Have you tried other preamps to determine whether it is the BHK or your system that prefer a direct connection from source to power amp?
I had previously used a Plinius M16 pre and Naim NAC52/Supercap.
It was better without them and I sold the Naim as a result.