Spectral DMA 400s arrive in New Jersey

[Brian Walsh]

Actually if you want to see nuts, accompany a professional musician auditioning pianos! It's not unlike audiophiles buying audio equipment; not to mention, musicians rely on their ears, not test instruments!

Better yet, get to know a good violin maker. Their work is fascinating yet probably as loony as it gets, thanks to their demanding clients. My friend Augustino in the city has stories, as you might imagine.

 

[mmatuva]

Does Keith Johnson have anything to do with the company now, or just that he designed some of the earlier units?

Who does their design work now?

I believe the follow-up post is correct, that he is centrally involved with the design and testing. On the CD player for example, the dealer I dealt with had a clear top so that one could see the circuitry built into the unit and inside there was a small plate signed off by Keith Johnson as I recall post testing. Of course, there could be stacks of those sitting around and put into the units, so it doesn't "guarantee" anything, but certainly suggests to me he is still very involved as the chief engineer and I know he goes on the road with Rick Fryer occasionally to demo the products and talk to consumers...seems like I saw a video or photos from the dealer in the Netherlands recently when the DMA 400s were released.

As an aside--really enjoyed the Wilson/VTL Hyatt room and demo at RMAF. Thanks...great work!

 

[Bruce B]

As an aside--really enjoyed the Wilson/VTL Hyatt room and demo at RMAF. Thanks...great work!

Thanks!

Yeah, I hadn't heard of anything lately about his involvement with the company. I was hoping it wasn't anything like ML.

 

[marty]

Marty,

Are you still using the TacT 2.2XP in your system?

Yes I am. Much of what I might have to say on the subject is found in the thread I referenced in the opening post. But a few more thoughts are appropriate to share as my thinking continues to evolve there as well. To begin, I think we can agree that almost every audio engineering choice has strengths and weaknesses. The use of DSP to perform a difficult job of implementing a crossover between disparate components and for performing EQ is no exception. It is worth noting that DSP is almost a de facto standard in today's production of almost CD/SACD so there are certainly professional as well as lay folks like me that find it solves a number of audio problems effectively. It's not really worth having a discussion over whether there are attributes there that are beneficial.The answer most assuredly is yes and those are likely to be application specific. Similarly, we all know that any device also brings baggage with it, whether it is an inherent coloration or a failure to execute its use to optimum advantage. So pick your poison. In my case, the most effective solution for dealing with the crossover/EQ issues was such that I thought DSP as implemented by a highly modified TacT 2.2XP unit solved more problems than it created, and in fact, does so rather well. But let's put this into historical perspective. My Pipes/sub system is about 10 years old and the DSP technology for how to "glue" these together were implemented about 8 years ago after I realized that analogue solutions were plainly disappointing. But much as changed since then.

What I am considering now is an alternative approach that just may allow me to consider using a speaker system capable of true seamless full-range 20Hz-20KHz performance that is satisfying for full orchestral SPL reproduction, but potentially arrived at without DSP. When the Wilson X2 Alexandria's came out, I was disappointed to hear that they really were devoid of the bottom octave of bass in several systems in which I heard them (and these were in very good rooms with great associated gear). However, by running the speaker full range, and augmenting them with JL subwoofers, I found newfound respect and optimism for the overall performance such a system could achieve. I have heard this approach used successfully in Steve's system (both in Danville as well as his current So Cal home) and in Brian Flower's excellent system in DFW. What I always tried to emulate after hearing their systems was the phenomenal performance of the Wilsons in the area that was my weakest link- the dreaded 80-200 "valley of death". Try as I might, there was, and still is, no way I can capture the pristine linearity in which the big Wilson's traverse this range which covers mid bass to upper bass so seamlessly into the lower midrange. Both Steve and Brian use their JLs rolling in steeply (24dB/octave) below 42 Hz with minimal gain so as to now make their Wilsons extend into the nether regions of bass which was simply non-existent without the JLs. So here we have very different ways to approach a problem, with two very different solutions. I'm aspiring to create a system capable of truly deep base that add to the Pipedreams excellent attributes elsewhere by crossing my Pipes into JL Gothams by fine-tuning a DSP crossover and EQ to get a seamless transition in that critical 20-200 area and the results ain't bad at all. But you should see the bizarro DSP EQ curve that's required to pull this off. It's so non-linear that it would make you reach out for dramamine because you would get nauseated from looking at that curve. More than that, it has taken several hundred hours of listening to get there since changes of 0.1dB can make the difference between good and really bad performance. That's right, 0.1dB. But forget the DSP curve. Its the results that count and the end result as I mentioned is actually quite good. But there is no way on god's green earth it has the linearity, and the performance of a full range speaker such as the Wilson in this area. The Wilsons of course are supremely well engineered using a hi level speaker crossover to yield truly excellent performance. Despite my best efforts, my use of a bastardized line level DSP crossover/EQ just won't match the Wilson's in this area for sheer seamlessness and here's that word again, linearity, in that part of the frequency range. Yes, the augmentation of the JLs to the big Wilsons also requires some art to make the transition to deep bass seamless, but I've heard done it to good effect in both Steve's and Brian's systems such that the liabilities are nominal and the overall sonic effect is extremely rewarding. Most important for consideration is that this solution was something simply not available to me, or anyone, 10 years ago.

So as I look to the future, I now see the emergence of speakers that I think are truly superb in most of the audio spectrum such as the Alexias, but have some limitations in the very deep bass regions that might be easily amended by running them full range and supplementing them with JL subs to yield overall system performance that I could live with. And such an approach would do so without the need for DSP. Such possibilities remain attractive for me to explore and I will continue to do so. In essence, the bottom line is this. What do you think the best way might be to build a fully full range speaker system? Do you want a talented speaker designer to do it using high level crossovers which yields a speaker that might have to be supplemented by the addition of a subwoofer without corrupting the integrity of the main system? Or do you want to try doing this yourself using some bastardized cockamoon DSP system that takes hundreds of hours to set up correctly to sound good and will still have some inherent non-linearities that can never be overcome without the proper laboratory equipment a true engineer might use to improve upon such a system? I can tell you this. The latter approach is not for the faint of heart and in fact, I truly think you have to have a screw out of place if you really want to pursue this exercise to begin with.

Let me close by saying I am encouraged that some folks are now trying to make genuine SOA speakers using DSP technology with very sophisticated engineering such as the Legacy Aeris (a speaker I have not heard). So it could be that advances in speaker design using DSP properly might further alter my thinking down the road. But now that conventional speaker design has reached new heights as manifest in such speakers such as the Alexia, or perhaps the new affordable "reference caliber" speakers like Paul Barton will supposedly debut at CES this year, one thing remains as true as ever. When it comes to choosing what you want to use in your home, there's vanilla, chocolate, strawberry and more. As my old friend and audio mentor Paul Heath used to say "You pays yer money and you takes yer choice".

 

[LL21]

What I am considering now is an alternative approach that just may allow me to consider using a speaker system capable of true seamless full-range 20Hz-20KHz performance that is satisfying for full orchestral SPL reproduction, but potentially arrived at without DSP. When the Wilson X2 Alexandria's came out, I was disappointed to hear that they really were devoid of the bottom octave of bass in several systems in which I heard them (and these were in very good rooms with great associated gear). However, by running the speaker full range, and augmenting them with JL subwoofers, I found newfound respect and optimism for the overall performance such a system could achieve. I have heard this approach used successfully in Steve's system (both in Danville as well as his current So Cal home) and in Brian Flower's excellent system in DFW. What I always tried to emulate after hearing their systems was the phenomenal performance of the Wilsons in the area that was my weakest link- the dreaded 80-200 "valley of death". Try as I might, there was, and still is, no way I can capture the pristine linearity in which the big Wilson's traverse this range which covers mid bass to upper bass so seamlessly into the lower midrange. Both Steve and Brian use their JLs rolling in steeply (24dB/octave) below 42 Hz with minimal gain so as to now make their Wilsons extend into the nether regions of bass which was simply non-existent without the JLs.

Agree with this observation...I find very few systems I have had the good fortune to hear match a big pair of Wilsons well set up with subs. My old X1/Grand Slamms with Velodyne DD18 crossed over 40hz (48db rolloff) are a setup I am very very happy with, and having heard Arrakis, Altair, Tidals, Grande Utopias, Aidas (and XLFs), I still find myself enjoying the way the Wilsons + sub present full-size scale effortlessly and much more fully. I know many of these speakers could also likely be worked with great sub setups...just have not had the opportunity to hear that as few dealers go thru the trouble unlike owners.

 

[cjfrbw]

Boy, the new room looks great, Marty, but I hope your old home was sold to an audiophile so that it's "clone" doesn't go to waste. The Spectrals' magic seems to extend to speakers other than Wilson.

 

[Al M.]

Great write-ups, Marty.

I am a tube fan who is impressed with Spectral as well, see:

http://www.whatsbestforum.com/showt...ates-Believers&p=217250&viewfull=1#post217250

As for integration of low frequencies, I am scratching my head about what I read here. I guess the problems that have to be addressed with DSP fiddling in 0.1 dB increments have to do with complex speaker systems and large rooms; my own listening room is much smaller than yours and everything can be and is simpler.

As for the lower regions of the sound spectrum, my Ensemble Reference minimonitors have effortless power in the low midrange, but without any box coloration that plagues larger dynamic speakers except the very best ones. A cello sounds like a cello, trombones and (bass) tubas are gutsy, the lower register of piano is powerful. The integration with my subwoofer, a REL Storm III, is totally seamless, no humps and bumps and dips -- really, no exaggeration. (I have no crossover to the sub from my main speakers, just the crossover in my sub itself.) It works beautifully, no DSP or anything required. It's not just my judgment. A music buddy of mine who likes jazz a lot and is a musician himself, was marveling at how realistic the double bass sounded on the avantgarde jazz classic "Out to Lunch!" by Eric Dolphy, remastered in 24 bit by Rudy van Gelder, the original engineer. Obviously, this would not be possible with anomalies in the nether regions. I even work with varying volume on the subwoofer all the time; the differences in bass output between recordings are simply to great to have it at a fixed volume (another reason why I find a subwoofer essential, and could not live with a full range speaker linear from 20 Hz upwards, unaided by a subwoofer).

I can listen with my speakers driven by triode monoblocks at just 15 W nominal output per channel without dynamic compression at realistic volume. This means regularly 90-92 dB SPL at orchestral peaks, with 95 dB at its max. (final brass chorale of Bruckner's 5th symphony, sounds really (!) loud; I usually make this the last piece of a listening session that contains it in order not to strain my hearing any further, since I feel the pressure on my ears afterwards even though the sound is clean); jazz and rock is usually at 80-86 dB continuous. Bass is powerful; I don't know if I hit 20 Hz straight, but recently I was listening to Bruckner's Te Deum, and I was shocked that at the choral opening "Te Deum lauda-a-mus!" there was this really deep, really black organ tone that made my entire wooden floor vibrate. So bass must go rather low.

Yet the success of my system is very much room-dependent. The room is of moderate size, 24 by 12 feet, with a height of about 9 feet. Sound pressure levels off very quickly behind my listening position relatively close to the speakers which extend across the width of the room (their outer edges are about 11 feet apart) -- just five or six feet behind my listening chair, SPL levels are already about 5 dB lower. To overcome that would be a huge deal for an amp/speaker combo; mine couldn't do it, certainly not at the same sound quality.

I am convinced that, if at realistic sound levels I wanted to make maximum use of the soundstage potential of a room that was just 3 feet wider (15 feet instead of 12 feet), my amps and speakers would not suffice. I would have to switch to Spectral amps and minimonitors (e.g. Magico Q1 *)) or other speakers that can play much louder at minimally the same sound quality. Also my subwoofer would need replacement (overall my investment would have to double at least, basically). And a really large room like yours appears to be? An exponentially greater expense would be required to at least replicate my sound quality at such a scale, including convincing microdynamics which are of utmost importance to me.

(I do know from listening at home that the Spectral DMA 260 can reproduce microdynamics really well (and I expect the DMA 400 to be no less a performer in that area) -- the very first solid state amp with great microdynamics that I have ever heard, a huge technological leap forward. In a large room I would go with Spectral anytime; I don't think that highly of high-powered tube amps.)

So yes, while I can have great and powerful sound at realistic volumes in my room, for sheer scale I would have to go an entirely different route (starting with another room). In that sense your system, Marty, is way ahead of mine -- but from reading your posts it seems that the pursuit of reproduction of large scale introduces its own problems, and opens a whole can of worms, even more so than I had already anticipated from my own listening experience with systems in large rooms. If you can overcome that, and it appears that you did to a high degree, good for you. But apparently it takes a lot of work. How much work it takes not just for you but also for your amps seems clear from the fact that even such powerful amps as your Spectral DMA-400 are sweating at some passages on your speakers in your room when asked to reproduce at realistic volume.

By the way, regarding your problem area below 200 Hz, have you thought about room treatment? I don't see much of it in your photos.

____________________________

*) although I am not yet convinced of Magico's. I have heard the two-way floorstanding Magico S1 speakers and while they sounded fine until 85 dB SPL, at 90 dB orchestral peaks they sounded heavily congested (driven by Spectral DMA 260). A caveat though: the room at the dealer was considerably smaller than mine, and acoustic treatment was of lesser quality

 

[Steve williams]

Marty's room is heavily treated. He uses tufted wall coverings as well as special drapes along with the high recessed ceiling

I can tell you that I have heard his system in Dallas and this new room according to Marty is virtually identical in size to his Dallas home. I can tell you that IMO Marty's system is one of the best on the planet so I am guessing that if anything this one will be better

 

[marty]

Al,
Wonderful and thoughtful remarks. I like your approach very much. As Steve noted, the room is heavily treated but the idea was to make it a functionally looking "family" room rather than an audio nerd lair. Sound considerations were built-in from the ground up but are not necessarily visible . To begin, the walls are double sheet-rocked (the single best sonic benefit per dollar there is), the floor is concrete, and the wall treatments have specific acoustical properties in both the visible layer and underlayer, as do the drapes. Pictures have selected Dow Corning material behind them and the under-carpet floor padding was chosen with sonics in mind as well. The oval recessed ceiling contains Helmholtz resonators under the fabric on the beveled walls that serve as bass traps. Sprayed open cell foam was used to fill any cavities behind the walls (i.e adjacent to the fireplace) or between walls to make the room resonant free. Fortunately, because the room is large, one can get away with more "sins" but fortunately, the overall sound is quite good and pleasing. Of course, the proof is in the pudding. Attached is the on-axis room response, which was taken at the listening position 14 feet from the speakers (thus the LF and HF roll-offs appears significantly more attenuated than if you took a "typical" frequency response measurement at 1 meter). Although DSP allows for almost infinite adjustment in order to achieve this response, the speakers themselves above 150Hz require hardly any tampering. The vast majority of the action is below that, which of course is where room boundary effects are their most invasive.

 

[Scott W]

Hey Marty,

The new room looks just as awesome as the old room. I sure wish Bill and I had made it back to listen to your system before you left DFW. Maybe a road trip is in order

Scott

 

[Bruce B]

Attached is the on-axis room response, which was taken at the listening position 14 feet from the speakers (thus the LF and HF roll-offs appears significantly more attenuated than if you took a "typical" frequency response measurement at 1 meter).

What is the smoothing factor of this?

 

[LL21]

What I am considering now is an alternative approach that just may allow me to consider using a speaker system capable of true seamless full-range 20Hz-20KHz performance that is satisfying for full orchestral SPL reproduction, but potentially arrived at without DSP.

When the Wilson X2 Alexandria's came out, I was disappointed to hear that they really were devoid of the bottom octave of bass in several systems in which I heard them (and these were in very good rooms with great associated gear). However, by running the speaker full range, and augmenting them with JL subwoofers, I found newfound respect and optimism for the overall performance such a system could achieve. I have heard this approach used successfully in Steve's system (both in Danville as well as his current So Cal home) and in Brian Flower's excellent system in DFW. What I always tried to emulate after hearing their systems was the phenomenal performance of the Wilsons in the area that was my weakest link- the dreaded 80-200 "valley of death". Try as I might, there was, and still is, no way I can capture the pristine linearity in which the big Wilson's traverse this range which covers mid bass to upper bass so seamlessly into the lower midrange. Both Steve and Brian use their JLs rolling in steeply (24dB/octave) below 42 Hz with minimal gain so as to now make their Wilsons extend into the nether regions of bass which was simply non-existent without the JLs.

Hi Marty, you have more experience than I do, it seems clear (to me). That said, in reading your words above, I think about the Genesis 1.2 4-tower or the Arrakis + JL Gotham Subs. There is something so endless about their dynamic range, ability to effortless fill a room like yours without stretching...and given their dynamic capability which I have heard myself in reasonably big rooms...I do wonder if you have considered them.

Actually, I have to imagine you have...and look forward to any thoughts you may have on these 2...as they are the 2 speakers at the top of my own personal list when it comes to effortless, organic, all-out dynamic power and yet grace and nuance.

 

[marty]

I don't really know the Genesis speaker (at least the current ones) but I sure do know about Arrakis. Fabulous speaker. Got to hear it in Maine at Andy Payor's place about 2 years ago. (The guy also knows how to BBQ lamb like you wouldn't believe). But those are big ticket items. When the time comes, if I were shopping in that price range, I'd consider the big Wilson's, Raidho 4.1 and Gryphons as well. At close to 1/2 of that, the Sonus Faber Aidas are also very attractive. But lets get real. I'm probably shopping in the price range of Alexias, which, at 25% the cost of the big Wilsons, Arrakis etc, are more in my ball park. I also wouldn't be surprised to see Andy Payor leap frog the Alexia with something priced in between the Alexia and the Maxx's that could well be worth considering. My real hope is that Paul Barton will knock one over the center field fence soon by unveiling his SOA assault for a very affordable price (20K?). 2014 CES debut? Wouldn't that be something!

 

[Al M.]

Thanks, Marty, for posting the on-axis response in your room at 14 feet for the speakers, with the roll-offs at either frequency extremes. That clears up things quite a bit. I checked in my room for a similar phenomenon. Indeed, a few feet behind my listening chair not just the SPL diminishes considerably, but the lower midrange down to the very bass bottom considerably looses power. Now I understand why you would need DSP. I wonder how other speakers, like the Alexias that you mentioned, could overcome that room response problem (you would augment them with a subwoofer, but there is still the issue with the 80-200 Hz range).

On the other hand, I have powerful sound, as described, at my listening position. It is much closer than 14 feet as in your room. The center points of my speakers and my listening spot form an equal-sided triangle, with about 10 feet distance on each side. That means I sit only about 6 feet and a few inches away from the mid-point between the speakers while they almost go across the entire room (with 11 feet between their outer edges). Yet also at 7 feet from the speakers I would still have the same kind of sound, only further back it changes.

As for room treatment, I am glad you took such elaborate measures. I guess neither you nor I nor Steve (and others) need to convince one another of the utmost importance of room treatment. Yet I hadn't thought much about it until last year, when my alarm bells went off after I could hardly hear the very substantial difference between the Berkeley Alpha DAC 2 (which I finally purchased after having the room fully treated) and my old Wadia 12 DAC. I did not pay too much attention before, because the tonal balance in my room was just fine. Yet the sound often seemed to scream at me and I had a flat soundstage. I also eventually figured out that room treatment might be beneficial after having heard the great transformation of sound from a friend's system after he moved it from one room to another, which had much better acoustics. The room treatment did not change my overall tonal balance, but everything else. Here are my observations about the effects in an email to Paul at Goodwin's High End, which Acoustic Sciences Corp. decided to publish on their website (there are a few minor formatting issues):

http://www.acousticsciences.com/goodwins-hi-end-customers-review

These observations were made when I had all my sound panels (Tri-Panels), yet just two tube traps. Now that I have six traps (forming three nice 'Greek columns' of stacks of two on the wall behind my speakers). the effect is even more pronounced (and as I mentioned, I changed the DAC; my bass is also more extended and powerful since that change). I might go so far as to say that the room treatment was the single most important upgrade to my system.

 

[Al M.]

In the attachment is a picture of my room with tube traps. The two Tri-Panels that you see stacked on top of each other in the left corner previously had been on top of the first two corner tube traps when I wrote my observations (a lot of those panels are dispersed as single units across the side walls of the room).

View attachment 11779

 

[LL21]

I don't really know the Genesis speaker (at least the current ones) but I sure do know about Arrakis. Fabulous speaker. Got to hear it in Maine at Andy Payor's place about 2 years ago. (The guy also knows how to BBQ lamb like you wouldn't believe). But those are big ticket items. When the time comes, if I were shopping in that price range, I'd consider the big Wilson's, Raidho 4.1 and Gryphons as well. At close to 1/2 of that, the Sonus Faber Aidas are also very attractive. But lets get real. I'm probably shopping in the price range of Alexias, which, at 25% the cost of the big Wilsons, Arrakis etc, are more in my ball park. I also wouldn't be surprised to see Andy Payor leap frog the Alexia with something priced in between the Alexia and the Maxx's that could well be worth considering. My real hope is that Paul Barton will knock one over the center field fence soon by unveiling his SOA assault for a very affordable price (20K?). 2014 CES debut? Wouldn't that be something!

Hi Marty...thanks for your comments...always enjoy them and learning from them. I will say, I was very very impressed by how well the Alexias played Dark Side of the Moon on the Metronome Kalista Ref...exceptionally large, full and complete soundstaging. Well beyond the speakers, but more importantly...a very very solid imaging outside of the speakers. I was not expecting that, particularly given how many auditions I have done in that room with much bigger speakers (XLF, Grande Utopias, Q5s, etc).

The nice thing about Wilsons is that you can use the resistors to boost, lower dispersion of the tweeters and mids so as to even out in-room response based on dimensions, etc. That makes a big difference imho when used with precision. I cannot say anything about your room interactions with the Alexias, but I can say their upper bass power was something I specifically remembering was very impressive. Good luck and look forward to hearing about your travails.

BTW, for the price of a new Alexia...you could just about get a second hand pair of Wilson X2 Series 2...for sheer scale, that would be quite something and literally give you exactly what you earlier said you were using in your mind as the model to pursue in your room for scale, effortless. That's the great thing about this hobby...with patience and discipline, all the SOTA can be had at fractions of the original retail.

 

[gshelley]

Marty,
Great write up. Thanks for sharing.
I recall well the evening Brian brought me over to your Westlake place. The 'in the room' sound of Frank Sinatra along with the bass effect on Chris Johnson's Roadhouse & Automobiles track was very memorable.

Can you share more info on the hemholz bass traps?
Considering a similar approach in my room. Need help taming those low bass notes

 

[puroagave]

Marty, an enjoyable review. have you detected any thinness in the low bass? I recently acquired some pre-loved spectral amps to play with and they all run with 10k input impedance. my friend who is a tech warned me spectral amps dont play well with most tube preamps (>300 ohm output) which pretty much eliminates all ARC preamps and all but the most current CJ gear. looking at VTL's site your pre likes to see a higher load than the spectral (20k or more).

sure enough the spectral amps sounded 'fuller' in my system substituting a SS pre and ditching the CJ 17LS, my speakers only reach to about 35hz in-room and it was audible. I'm borrowing a CJ ET5 next week (100 ohm output) and will see if I can get them to gel.

 

[LL21]

my friend who is a tech warned me spectral amps dont play well with most tube preamps (>300 ohm output) which pretty much eliminates all ARC preamps and all but the most current CJ gear...sure enough the spectral amps sounded 'fuller' in my system substituting a SS pre and ditching the CJ 17LS, my speakers only reach to about 35hz in-room and it was audible. I'm borrowing a CJ ET5 next week (100 ohm output) and will see if I can get them to gel.

interesting...I have read about this though fortunately have not had to do this system matching. Look forward to reading about how the CJ ET5 work for you.

 

[marty]

looking at VTL's site your pre likes to see a higher load than the spectral (20k or more).

Hi Rob,
I'm not sure I would agree. The VTL 7.5III specs are clear. They say nothing of the input impedance requirements of the gear it is driving.. Its OWN input impedance is 50K ohms (20K min). But very clearly it will deliver full output, 30V, into "10K or above". I've also confirmed that they will drive a 10K load with Luke Manley.

Output Impedance 25 Ohms (Max 150 ohms at 10Hz)
Input Impedance 50K Ohms (20k ohms min)
Maximum Output
Voltage < 1% THD
30V into 10K or above 10Hz – 200kHz +/- 1 dB
10V into 600 ohms

As far as low bass, I would say I find myself easily tempted to have too much bass, which necessitates a tweak to my DSP curve. I have system weaknesses, believe me, but bass thinness is the least of them!!