ack's system - end of round 1

dan31

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Correct. I gave up waiting years ago.

I admire Spectral for producing the products that interest them. I agree with their dedicated CD player design. I understand why they do not want to get into the DAC market. I cannot understand why they have not produced a dedicated phono preamp.

It would be right in their expertise as an all analog component. My guess would be a lack of interest at Spectral. Perhaps the Asian market dominates their business and keeps them focused on amplifiers and red book digital.
 

ack

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A breakthrough in digital?

My son plays the trombone and euphonium (he's the lead trombonist in the high school Big Band), and in the last month or two, as I continue to modify my Alpha DAC, I have noticed him taking a very serious interest in the sound of wind instruments coming out of this system; so much so that he interrupts his computer gaming to come upstairs and sit with me and listen attentively. One of the best recordings for wind I have is the Proteus 7 CD "For Your Ears Only" from Dorian that we have discussed before here and elsewhere.

I recently wrote to the local group here that I've had a breakthrough with this DAC, and I bet they are still laughing. The time came to compare it head to head with the Spectral SDR-4000SV, using my own interconnects.

"It lacks dynamic contrast and bite compared to your DAC; it's not as realistic; things are more homogenized and more flat" - Son, reflecting on the Proteus 7 CD.

To make a long story short, the 4000SV has more dynamic drive in the low end, a bit more well defined midbass, but when it comes to the entire operating range of my electrostatic panels, the Alpha surpasses it in many, many ways, with more realistic timbre, higher dynamic contrasts, more vividness, clearer see-through transparency, and higher low-level resolution. The lack of that ultimate bite with trumpets and other wind instruments is evident in the 4000SV; things are a touch rounder, perhaps more pleasing. Treble smoothness is higher with the Alpha. With large-scale orchestral, like the Telarc Carmina Burana reissue by FIM that I mentioned recently, and many others, the separation of instruments and chorus with the Alpha is superior, as is the leading edge of the bass drum. All in all, when it comes to absolute realism, this modified Alpha comes ahead, at least to these ears, save for that lack of bottom-end oomph. Perhaps it's all about system and preference matching.

I'll wrap it up as follows: on the Proteus 7 CD, my son has played along with the music, and the similarities between his trombone and what comes out of the speakers using the Alpha is frightening close, his playing being still a bit more dynamic. Well, this is what I got after 2.5 years worth of listening and modifying, and it's a great place to be.

EDIT: Just noticed the slew rate of the 4000SV https://www.moremusic.nl/spectral/SDR-4000SV.html and it's much slower than the preamp's and amps', at 400 V/us; maybe that's what I am hearing and perhaps a bit of noise...
 
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sbnx

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We played the test scale on the CD of Stockhausen piano pieces from Stockhausen-Verlag (engineering supervised by the composer himself), and I was struck by the evenness of timbre QUOTE]

Hello, Could I ask which Stockhausen CD you were listening to?

Thanks,
Todd
 

Al M.

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Hi Todd,

it's complete piano pieces played by Ellen Corver, on Stockhausen-Verlag CDs 56 A-C:

http://www.stockhausencds.com

The test scale is track 10 on the first CD.
 

sbnx

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Thanks Al.
 

sbnx

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Just got the CD set in the mail. Very, very nice. And the chromatic scale is exactly what i have been looking for. Thanks for mentioning it.

Enjoy,
Todd
 
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ack

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It really is more than just the sound...

It is also about the friendships and the great offline discussions! Last night, I had the privilege of hosting Al M, PeterA and Vlad (a low-key member here, and obvious wine connoisseur) for music and dinner.

I have branded Al "Mr. Beautiful Ears" and it is uncanny how he can pick up changes in my system that I have purposely not discussed with anyone. For example, I replaced a 0.25 ohm resistor in my rear-woofer's crossover with a 0.33ohm, and Al said "your bass has improved" - I did hear significant improvement back when I swapped the resistors, but how the heck can an outsider hear it too, just like that! And he convinced me to turn up the DAC's volume to 48.5. Thank you Al!

I love cooking on the weekends, having being burned by so many "high end" restaurants that just can't cook a tasty meal, and I made rack of lamb and paella, plus Greek salad. Nothing was left in the end.

On the audio front, I think the highlight of the evening was For Duke and the Sheffield Drum Record, for the effortless and significantly realistic sound... I also had my son blow a loud note on his trombone to get a sense of true dynamics, and he hit 118dbA at two meters distance.

Guys, thanks, and we will do it again. Happy Thanksgiving!

IMG_3846.jpg

IMG_3847.jpg
 
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PeterA

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Top notch, Tasos. Thanks so much for inviting us. The food was simply fantastic. Best lamb chops and authentic Greek salad I've ever had. Yes, and Vlad brought a really good bottle of red wine.

The sound has improved significantly since I was last there. You have made significant progress in the sense of realism for me, and particularly in the more natural mid frequencies. You've added weight and body which the system lacked somewhat before. Well done. Congratulations on the improvement. It was a really enjoyable evening.
 

bonzo75

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After eating all that, anyone can add weight and body
 
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VLS

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Great evening Tasos. Indeed, many thanks for creating this well-rounded experience.

Since this was the first time I have heard your system I can’t comment on its improvement relative to earlier incarnations, but in its current state it was eye-opening (ear-opening?) for me. You have clearly attained the happy combination of effortless, explosive dynamics, great transparency, as well as tonal density, which made good recordings uncannily natural and life-like. This – along with Al’s system, which I have heard earlier – has established another reference point for me of what’s possible given a clear vision of the desired outcome, an empirical mindset, and impressive perseverance.

All that plus great food and erudite conversation!

Vlad
 

ack

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Thank you Vlad, and really glad to have met you in person!

So here's a horror story, developing right this moment: myself and my wife are out shopping, and my son called. "Dad, how do I play a record?" - cold sweat is running down my face! I call him up in panic; he figured it out, and of all pieces, he's playing Mahler's 2nd with the BSO - my favorite recording of it. Oh, they grow up so fast! I love the kid, and I hope he's not damaged anything. I am really panicking right now. Wish me luck! LOL :eek: A new audiophile in the making!!!!!
 

Al M.

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Thanks, Tasos, for a great evening, and to all for the great company. Yes, lamb chops and Greek salad were the best that also I have enjoyed, I agree with Peter. Vlad's Tamaral 2010 wine was exquisite, and I also loved your Greek wine.

I agree, Tasos, that For Duke and the Sheffield drum track were highlights. I was just stunned how good For Duke sounded, with such realistic, full bodied brass. The dynamics on both records were explosive indeed. I heard the improvements of your bass over last time on some drums on the "James Bond" CD (Proteus 7), which were as good as I have ever heard from this recording. Mightily impressive.

As for me having "beautiful ears" (hehe), I wish that would extend to me always knowing the best solutions for my own system. Unfortunately this is not always the case, but I get it done With a Little Help From My Friends ;).

In any case, I also noticed that your treble was a bit more attenuated than last time, and you confirmed that by pointing out a change from 1.3 to 1.5 Ohm for the value of the resistors for the panel (I hope I get those numbers right).

Last time I thought the tonal balance was perfect. Nice full bodied midrange, but still well pronounced high frequency extension that let each instrumental timbre shine.

This time I thought the sheen on orchestral violins was a bit too attenuated, as I told you yesterday. I also thought I was missing some timbral micro detail on string quartet and on the brass on the "James Bond" CD. Some leading edges of the brass also had a bit less bite than I was used to from your system, which intrinsically is capable of tremendous transient differentiation, from nuanced rounding or attenuation to brutal attacks (the realistic brass bite on For Duke though was excellent). The somewhat closed in nature of some voices seemed also related to the slightly toned down treble.

Recently I was dealing with all those exact issues in my own system. After I removed the CD transport from the isolation transformer, the tonal balance was tilted a bit "downward". At first I found this very alluring, but a breaking point was reached when I discovered that some female voices had lost their transparency and their startling presence. In my case I could easily solve the issue by again slightly increasing the toe in of the speakers. A relatively full tonal balance was still retained.

It is always a balancing act of finding a tonal balance that comes closer to the real thing while still retaining all the information and transparency of the recording. I thought the last time I visited you had nailed it perfectly (and I gave an enthusiastic report about your system's capabilities on this thread), this time I found it still enjoyable, but less as I would prefer it. Still, impressive sound overall, and indeed, very nice improvement of the bass.
 
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marty

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It really is more than just the sound...

It is also about the friendships and the great offline discussions! Last night, I had the privilege of hosting Al M, PeterA and Vlad (a low-key member here, and obvious wine connoisseur) for music and dinner.

I have branded Al "Mr. Beautiful Ears" and it is uncanny how he can pick up changes in my system that I have purposely not discussed with anyone. For example, I replaced a 0.25 ohm resistor in my rear-woofer's crossover with a 0.33ohm, and Al said "your bass has improved" - I did hear significant improvement back when I swapped the resistors, but how the heck can an outsider hear it too, just like that! And he convinced me to turn up the DAC's volume to 48.5. Thank you Al!

I love cooking on the weekends, having being burned by so many "high end" restaurants that just can't cook a tasty meal, and I made rack of lamb and paella, plus Greek salad. Nothing was left in the end.

On the audio front, I think the highlight of the evening was For Duke and the Sheffield Drum Record, for the effortless and significantly realistic sound... I also had my son blow a loud note on his trombone to get a sense of true dynamics, and he hit 118dbA at two meters distance.

Guys, thanks, and we will do it again. Happy Thanksgiving!

View attachment 58972

View attachment 58973
You guys are really starting to piss me off. You're too far away to drive, the plane fare from Newark to Logan is obscene, your menu is unbeatable and your wines are too tempting. Arghhh....
 

ack

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Thanks Al! Yeah, the balance is now slightly different, with slightly lower treble as you described it; I voiced it after my son's trumpet and our friends' pianos; I felt that before it was a tad bright. I think the sound now is more natural, and next time I will play the RR Rachmaninoff Symphonic Dances on HDCD and LP, the RR Berlioz Fantastique and the Brahms violin/piano sonatas, and I think you will understand. Of these, the tremendous final crescendo of the Dances will probably be the most convincing test - both on CD and LP - and it has immense treble content and power, and you will see how controlled, natural and not bright it sounds (it's still not "perfect"). More treble can sound exciting, more resolving, but controlled treble is more natural.

All this, though, is testament to how great your ears are, and you pick up everything!

@marty LOL :)
 

ack

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Pigtails on the menu????

Despite the great sound I am getting, I needed to replace the Cardas jumpers I was using for this external resistor bank on the panel, with the MIT Oracle pigtails.

I was right in suspecting that the Cardas was storing some energy, which is unleashed with the MIT. Or as they say, You Have No Idea what they do in terms of vividness, timbre and articulation. I still cannot remember what I use on the return side, but they are very short and very good.

IMG_3850.jpg
 

Al M.

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Thanks Al! Yeah, the balance is now slightly different, with slightly lower treble as you described it; I voiced it after my son's trumpet and our friends' pianos; I felt that before it was a tad bright. I think the sound now is more natural, and next time I will play the RR Rachmaninoff Symphonic Dances on HDCD and LP, the RR Berlioz Fantastique and the Brahms violin/piano sonatas, and I think you will understand. Of these, the tremendous final crescendo of the Dances will probably be the most convincing test - both on CD and LP - and it has immense treble content and power, and you will see how controlled, natural and not bright it sounds (it's still not "perfect"). More treble can sound exciting, more resolving, but controlled treble is more natural.

All this, though, is testament to how great your ears are, and you pick up everything!

@marty LOL :)

Tasos, after some changes involving speaker toe-out for the cold winter days, a temporary rise in outside temperature following that, and while currently demoing DaveC's modded SurgeX (which I like) now I have a tonal balance that goes more in the direction of your current one. Solo voices are still transparent, but at a tipping point where a little more speaker toe out would make them feel slightly closed in. The treble sheen on string instruments is reduced, which may give the impression of somewhat less micro-detail of timbre on string quartets, for example. Solo violin though still has lots of micro-detail even though perhaps a bit less than before, and despite the toned-down balance, triangle still rings through. The sound overall seems more in accord with what we tend to hear live. I was surprised that, while the sound of the solo violin at our last concert in the Ayer Mansion was harmonically rich and had tremendous energy, there was less micro-detail from the friction of the bow on the strings than I had expected. -- I did hear more detail live on other occasions, also at the Ayer Mansion, but also just that smaller amount of detail in other live concerts.

The upside of my current sound is more weight in the lower midrange, and a solo trombone piece that I had listened to lately now sounds rather convincing compared to what I heard your son play on that instrument. Trumpet also has more body. I can appreciate when you write that you voiced your system after your son's trumpet. Orchestra has more heft, the sound of string quartets is more wooden, and solo voices have a beguiling warmth that still feels natural.

There is only one downside, which is that, as I had observed in your system, the sheen on orchestral massed violins is reduced to a point where the sound feels a tad dull. I now remember that I did hear more of such a toned down sound at a recent concert that Ian and I attended of the NEC Philharmonia in the wooden hall of the New England Conservatory in Boston, but the string sound still had more air. While a good system can reproduce air quite well, it is hard to get to that last bit of air from instrument and hall information at a toned down tonal balance. Nothing beats an actual concert hall.

So yes, I like the sound overall and am fascinated by it. Will I keep it and not toe in the speakers just a tad more again? Time will tell.
 
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ack

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now I have a tonal balance that goes more in the direction of your current one

And I still feel this is more accurate.

The sound overall seems more in accord with what we tend to hear live. I was surprised that, while the sound of the solo violin at our last concert in the Ayer Mansion was harmonically rich and had tremendous energy, there was less micro-detail from the friction of the bow on the strings than I had expected. -- I did hear more detail live on other occasions, also at the Ayer Mansion, but also just that smaller amount of detail in other live concerts.

Exactly Al!

The upside of my current sound is more weight in the lower midrange, and a solo trombone piece that I had listened to lately now sounds rather convincing compared to what I heard your son play on that instrument. Trumpet also has more body. I can appreciate when you write that you voiced your system after your son's trumpet. Orchestra has more heft, the sound of string quartets is more wooden, and solo voices have a beguiling warmth that still feels natural.

Exactly

There is only one downside, which is that, as I had observed in your system, the sheen on orchestral massed violins is reduced to a point where the sound feels a tad dull. I now remember that I did hear more of such a toned down sound at a recent concert that Ian and I attended of the NEC Philharmonia in the wooden hall of the New England Conservatory in Boston, but the string sound still had more air. While a good system can reproduce air quite well, it is hard to get to that last bit of air from instrument and hall information at a toned down tonal balance. Nothing beats an actual concert hall.

Bingo again

So yes, I like the sound overall and am fascinated by it. Will I keep it and not toe in the speakers just a tad more again? Time will tell.

All of that is great, but can I throw you a curve ball right now? Wait till you hear these MIT Oracle pigtails; and I will say no more, but I will record your reaction next time we meet over here. Notice what I said above: "unleashed" - said otherwise, capacitance is such a killjoy

If I were to suggest one thing about your system, it would be this: adjust toe-in for best image, and then adjust the tweeter output with a good resistor. I think I've mentioned that in person as well.
 

Al M.

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And I still feel this is more accurate.

Exactly Al!

Exactly

Bingo again

Well, I guess we compare our live experiences of unamplified music. It is good and in my view essential to have such a reference. Some caveat though, I have heard wildly differing tonal balances in diverse concert halls, but that is a whole other story.

All of that is great, but can I throw you a curve ball right now? Wait till you hear these MIT Oracle pigtails; and I will say no more, but I will record your reaction next time we meet over here. Notice what I said above: "unleashed" - said otherwise, capacitance is such a killjoy

I look forward to that, Tasos!

If I were to suggest one thing about your system, it would be this: adjust toe-in for best image, and then adjust the tweeter output with a good resistor. I think I've mentioned that in person as well.

The beauty of my monitors (and for that matter, most monitors) is that they image well no matter what. There may be slight differences at varying toe-in angles, but nothing that makes imaging go from good to mediocre, unlike with many larger speakers. I can fine-tune tonal balance easily with slight changes in toe-in angle. For some dumb reason I did not discover this until about 2 months ago, even though I had taken advantage of the phenomenon with my old monitors. I thought the new ones were less sensitive to tonal balance changes by toe-in. While that may be the case within a certain range of angles, there is still tons of wiggle room to adjust, without employment of a resistor.
 
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Al M.

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On Saturday I had the pleasure of again hearing Ack's system. He has restored the resistor values for the speakers to the greater treble extension that I heard the time before last, added MIT Oracle pigtails (see post #896) and worked some more on the crossover for the woofer (I think).

We compared the Schiit Yggdrasil Analog 2 DAC (Yggy2) that Ack had on loan from me for auditioning -- while I had been away on vacation -- with Ack's modified Berkeley Alpha DAC. Ack has already left some impressions on my system thread about the Yggy2, and now I could hear for myself why Ack is so enthusiastic that he bought one. I know that Ack's modified Berkeley DAC is considerably better than the stock unit that I had in my system as well (for example, the modified Berkeley does not congest on fortissimo massed strings as the stock unit does). Nonetheless, the Yggy2 was better in every way, and the differences were not even subtle.

One very obvious thing was that the Yggy2 has better rhythm; it is as good a rhythmic performer as I have heard, analog or digital. The differences with the Berkeley DAC were even greater than I had thought from remembering them in my system. Ack always thought my system had great rhythm, but his system with the Yggy2 in it also performed extraordinarily well. One thing that I noticed during the whole session was that the subwoofer was never in the way, unlike before; I suppose this may have to do with his latest crossover adjustments for the woofer in his modified Martin Logan speakers.

The Yggy2 also excelled in sheer speed. It was always incredibly precise and clean, from treble to bass. I would never have associated the sound of the Berkeley with being "woolly", but in comparison it was, at least on some recordings. While I know from my own system that the Yggy2 has great speed, that speed was put under a magnifying glass in Ack's system.

The extreme treble register on piano was already impressive on Ack's electrostats with the Berkeley DAC, but the Yggy2 showed even more speed and purity. I have never heard such cleanness in the extreme treble of piano from a conventional speaker; nothing beats an electrostat where basically the entire membrane is a 'tweeter', and thus does not distort even with quick, strong attacks in the treble, which are portrayed also in a dynamically convincing way on Ack's modified Martin Logans, held in tight grip by the Spectral amps. The piano sound on a great recording of Busoni's fascinating piano concerto (Gerstein on piano, with Boston Symphony) was chiseled out with extreme precision, and also reflected the somewhat metallic character of a Steinway Grand Piano with open lid; the Berkeley DAC did not manage to do that, and in comparison sounded indeed a bit woolly on the piano. On other recordings the Yggy also correctly revealed the comparatively non-metallic sound of smaller pianos with apparently closed lid as accompaniment of, for example, solo violin. The Berkeley DAC just did not make the distinction. The Yggy2 also portrayed the orchestral sound with a more convincing body and precision than the Berkeley did. What sounded like a fantastic recording with the Yggy2 seemed a merely good one with the Berkeley.

As for timbral correctness, I brought another acid test with me, an extraordinarily well recorded CD with solo flute works by Stockhausen. I had noticed a large difference in timbre of flute between the DACs in my system. Flute sounds relatively light and very 'refreshing' on the Berkeley DAC, with apparently more timbral inflections. In comparison the Yggdrasil DAC portrays flute with a warmer, darker and more even tone. At first I was shocked about the difference, but more live experiences convinced me that the timbral portrayal of flute is correct on the Yggy2, rather than on the Berkeley DAC; most recently I heard in a concert that I attended with WBF members Peter A. and Madfloyd that warm, rather dark flute tone in Mozart's concerto for flute, harp and orchestra. While Ack's modifications have improved the Berkeley Alpha DAC, we heard in his system that the innate differences on flute remained the same, with the Berkeley still having that 'refreshing' yet slightly artificial tone. This may be one of the rather obvious timbral differences why Mike Moffat, the designer of the Yggy2, says that he does not like the nowadays common delta sigma conversion (as in the Berkeley DAC) and instead prefers 'old-fashioned' ladder DACs, as the Yggy2 is one. Schiit sells lots of delta sigma DACs because they can be made much cheaper (all their $ 100 DACs are delta sigma), but when Moffat gets serious about design he makes ladder DACs.

There is also an incredible dynamic speed. Some passages on track 16 of the Proteus 7 brass ensemble CD "For Your Ears Only" (at 3'10", 4'14" and again half a minute later) feature very quick exchanges between trombones and trumpets, and the fast dynamic surges, even explosions, in those passages were absolutely incredible with the Yggy2 in the system. On the Berkeley DAC those passages fell flat dynamically, it was not even a contest. Those dynamic explosions with the Yggy2 in the system came closest yet of reminding me of a real brass band -- and that on electrostats (!) which are not typically known for their dynamic prowess. Yet typically they are not driven by such source and amplification. Hearing is believing, is all I can say.

While my system is very dynamic, and has been experienced as such by every visitor so far, it does not project the brutal dynamics in those passages as Ack's system does, with of course also the Yggy2 as source. The recording is not quite as in your face on my system and also sounds slightly darker, which of course can have an influence on dynamic perception. Yet it may well be that the intrinsic dynamic capabilities of my system are not quite the same, even though in other passages of that recording I hear terrific dynamics at home. Regardless, the fact that the dynamics in Ack's system are so explosive is enormously impressive and also an astounding testament to the capabilities of the Spectral amplification. The system shows the contrast in dynamic speed between the two DACs in a most incisive manner. I would assume that the amazing dynamic speed of the Yggy2 would make it a great source in a competent horn system.

All in all, the sheer speed of the Yggy2 is a great match for the speed of the Spectral preamp and amps. Ack's system, which sounded the best I have heard it, shows once more in its own way just how good the Yggy2 DAC really is.

Even among all this impressive sound from the system, we heard a real-life reality check. Ack's son Constantin played for us a bit on his tenor saxophone, and the sheer bluntness and presence of sound, as well as the enormous power and body in the low notes, combined with brutal dynamics throughout the range, puts anything to shame that we have heard from a stereo system. Constantin plays with an enormous fluidity of rhythm and phrasing, a true natural talent!
 
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