Thanks Ian. Corner frequency is the -3dB point people typically quote. It's fun to watch digital do presence, timbre and articulation, separation of instruments. The technology is sound, the implementation is apparently very hard.
ack's system - end of round 1
- Thread starter ack
- Start date
As Ack mentioned, yesterday I visited to hear his system. The resistor modification to his speakers, which also tones down the treble, has worked very well. The sound was closer to what you would hear live, where the treble is mostly not as prominent as typically from a stereo system. I have achieved a similar effect by speaker toe out (report forthcoming). Timbre is more convincing throughout, and there is also more body of sound in the lower midrange. This is to be expected as the interpretation of sound by the ear/brain interface apparently depends on the intensity of frequencies relative to one another, so that less energy in the upper treble translates to a perceived greater emphasis of frequencies downrange. Ack told me he did not change the crossover between panel and woofer.
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 throughout; you could not hear the transition between panels and woofer, even though body in the low register has increased. I must say, the speaker that Ack has arrived at with his modifications is impressive.
Dynamics were still excellent as always, and in some cases, perhaps especially in the bass, dynamic punch may have further benefited from the DAC modifications.
What also struck me was a greater differentiation of transients, where hard attack transients do not lose their 'edge', but other transients show more subtle shadings. I have found this increase of transient differentiation with the relatively recent insertion of my Octave preamp in the chain; in Ack's system it seems to be changes to his source, the Berkeley DAC, as his excellent Spectral amplification has not changed.
Resolution has increased, perhaps as a combination from both modifications to both speaker (see Ack's post from May 28) and DAC. As for timbral micro-detail, especially on string quartet (difficult to reproduce!) and orchestral massed strings, Ack's system now checks ALL my resolution boxes. It is as good in this area of reproduction as I have heard. I also found remarkable how the modified Berkeley DAC performed on my CD of Shostakovich Ninth Symphony with Mariss Jansons conducting the Oslo Philharmonic Orchestra (EMI). My stock version of the Berkeley DAC had been hardening up on fortissimo violins and showed less micro-resolution on strings, which was a clear disadvantage to my Yggdrasil DAC and one of the deciding factors in keeping the latter after the audition period. Now, one generation of resolution in my system further, and with the version 2 of the Yggdrasil DAC in my system, I was surprised how similar Ack's modified Berkeley DAC in his system was to the Yggdrasil 2 DAC in my system, keeping its cool on fortissimo strings, and presenting a similar fine string micro-texture throughout. The Berkeley DAC, which in Ack's version is now already 10 years old, obviously always had the potential, but the quality of implementation of its digital technology had to be helped along, and the result from Ack's hands is impressive.
Separation of instruments, another aspect of resolution, was fantastic throughout. You could so easily discern individual lines and their interplay in the music, it was incredibly immersive and enjoyable.
Tonal character overall was very enjoyable as well, with clear gains in realism, as already mentioned above. Woodwinds in the Shostakovich symphony sounded incredibly beautiful, including in the slow second movement which just bathes in woodwind sounds. You don't need a tube amp for that, top notch implementation of SS technology as in the Spectral preamp and amp fully suffice. I say this being a tube gear guy myself. All in all, with all the increases in overall system performance, the outstanding quality of the Spectral amplification, which I have long admired, was only further confirmed.
What I heard yesterday, with speaker and DAC modifications, was the best Ack's system has ever sounded. It is a major leap forward in performance. Congratulations, Ack!
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 throughout; you could not hear the transition between panels and woofer, even though body in the low register has increased. I must say, the speaker that Ack has arrived at with his modifications is impressive.
Dynamics were still excellent as always, and in some cases, perhaps especially in the bass, dynamic punch may have further benefited from the DAC modifications.
What also struck me was a greater differentiation of transients, where hard attack transients do not lose their 'edge', but other transients show more subtle shadings. I have found this increase of transient differentiation with the relatively recent insertion of my Octave preamp in the chain; in Ack's system it seems to be changes to his source, the Berkeley DAC, as his excellent Spectral amplification has not changed.
Resolution has increased, perhaps as a combination from both modifications to both speaker (see Ack's post from May 28) and DAC. As for timbral micro-detail, especially on string quartet (difficult to reproduce!) and orchestral massed strings, Ack's system now checks ALL my resolution boxes. It is as good in this area of reproduction as I have heard. I also found remarkable how the modified Berkeley DAC performed on my CD of Shostakovich Ninth Symphony with Mariss Jansons conducting the Oslo Philharmonic Orchestra (EMI). My stock version of the Berkeley DAC had been hardening up on fortissimo violins and showed less micro-resolution on strings, which was a clear disadvantage to my Yggdrasil DAC and one of the deciding factors in keeping the latter after the audition period. Now, one generation of resolution in my system further, and with the version 2 of the Yggdrasil DAC in my system, I was surprised how similar Ack's modified Berkeley DAC in his system was to the Yggdrasil 2 DAC in my system, keeping its cool on fortissimo strings, and presenting a similar fine string micro-texture throughout. The Berkeley DAC, which in Ack's version is now already 10 years old, obviously always had the potential, but the quality of implementation of its digital technology had to be helped along, and the result from Ack's hands is impressive.
Separation of instruments, another aspect of resolution, was fantastic throughout. You could so easily discern individual lines and their interplay in the music, it was incredibly immersive and enjoyable.
Tonal character overall was very enjoyable as well, with clear gains in realism, as already mentioned above. Woodwinds in the Shostakovich symphony sounded incredibly beautiful, including in the slow second movement which just bathes in woodwind sounds. You don't need a tube amp for that, top notch implementation of SS technology as in the Spectral preamp and amp fully suffice. I say this being a tube gear guy myself. All in all, with all the increases in overall system performance, the outstanding quality of the Spectral amplification, which I have long admired, was only further confirmed.
What I heard yesterday, with speaker and DAC modifications, was the best Ack's system has ever sounded. It is a major leap forward in performance. Congratulations, Ack!
Nice report Al. Very well written and informative. Congratulations Ack!
Thanks Al for taking the time to come down and for writing your impressions. I subsequently played my version of the Shostakovich with the BSO on DG and it's just not the same, frankly; some of their recordings continue to be challenged. This is the kind of stuff that other DACs attempt to mask.
The piano chromatic scale on the Stockhausen CD is a really good test of one's system, and I forgot to mention how linear it now sounds. One can easily tell anomalies up and down the spectrum with it.
I am sure the diodes are still breaking in. Still waiting for the Spectral DAC, LOL
@PeterA thank you as well
The piano chromatic scale on the Stockhausen CD is a really good test of one's system, and I forgot to mention how linear it now sounds. One can easily tell anomalies up and down the spectrum with it.
I am sure the diodes are still breaking in. Still waiting for the Spectral DAC, LOL
@PeterA thank you as well
@ack Thanks for sharing.
I hope 2020 sees the release of the SV phono stage.
Then hopefully an SV dac is next.
As you mentioned ; the Sv CD player is good that if they release a dac; it would have to equal or surpass this redbook player.
Looking to hopefully reading your posts about the phono stage next year. (Crossing fingers ) lol
I hope 2020 sees the release of the SV phono stage.
Then hopefully an SV dac is next.
As you mentioned ; the Sv CD player is good that if they release a dac; it would have to equal or surpass this redbook player.
Looking to hopefully reading your posts about the phono stage next year. (Crossing fingers ) lol
@ack Yes, I read that too but , looks like the 250s3 is just a replacement for the 240 as their “entry” level amp.
As to what has changed with it ; who knows I wish they were more descriptive.
Also looks like the 500s were indeed a limited edition run and are no longer being made.
So, you have quite the amps that are indeed very special and now even more exclusive.
I do think that 2020 will bring the phono stage.
Unless of course they release a two chassis pre amp that will be above the 30Sv.
I’m hoping for the phono stage. Although I’m not in the market for one but , there has to be so much pent up demand for it. Certainly it would be a major seller for them.
As to what has changed with it ; who knows I wish they were more descriptive.
Also looks like the 500s were indeed a limited edition run and are no longer being made.
So, you have quite the amps that are indeed very special and now even more exclusive.
I do think that 2020 will bring the phono stage.
Unless of course they release a two chassis pre amp that will be above the 30Sv.
I’m hoping for the phono stage. Although I’m not in the market for one but , there has to be so much pent up demand for it. Certainly it would be a major seller for them.
I know. But no laughing matter, really - it's putting the dealers' credibility on the line, time and time again.
Spectral is a tough nut to crack. They keep making amplifiers, it must be what dealers are requesting. We know Spectral do not run as a normal audio business. They will only produce products they want to produce.
I have given up on a Spectral phonostage. My Aesthetix Io feeds my Spectral preamp some great vinyl sound.
I do think about the 4000SV CD player, it is exceptional and really makes sense given all of the CD's that have been produced. CD is still a large format in Asia.
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The 4000SV player is the only one I like in that entire line, and a cut above all of its siblings. I keep thinking about it myself, just trying to assess how close my modified Alpha DAC is to it. I am listening to the RR Symphonic Dances right now, and the sound is so clean and controlled unlike ever before; in the past, during the loud passages, it was edgy, distorted, and unbrearable. Right now, it sounds so analog, with the help of HDCD.
@dan31 I can agree with @ack that the SV CD player is very special indeed.
IMHO, i don't think we will a Spectral DAC soon and will see the phono before as perhaps even 2020.
I've personally yet to hear any computer based file or streaming solution; regardless of the bit rate, file format or DAC. To surpass the digital physical media.
Maybe Spectral will prove me wrong but, any computer audio regardless of the price is at the mercy of noise, distortion and jitter; introduced by computer networks.
Just reading the forums and you'll read about everyone spending thousands for convenience and try to increase performance for computer/network audio
We are getting there but, for now and IMHO physical media quality trumps (no pun intended) computer audio' s convenience .
On players like the 4000SV; that difference ; especially in an all Spectral SV system is quite special indeed.
Long live the compact disc.
For now at least...
More Berkeley DAC fun (as if anyone cares)
Somewhere in these pages I think, someone said that the Berkeley volume control - going from 0.0 to 60.0 - adjusts in 0.1dB increments. I have been able to verify that with test tones, and more importantly, voltage is halved at -6dB (54.0) and quartered at -12dB (48.0) from the reference; more precisely, based on the same measurements, the drop is respectively -6.0206dB and -12.0412 dB, precisely as it should be - a major engineering feat indeed.
However, as I have posted in the past, digital volume controls frustrate me, even if they don't lose resolution (as is the case with Berkeley DACs). The problem, as I have grappled with over the years, is that tonality changes with various settings, with certain settings sounding elevated in the treble, with others articulation suffers, or bass drops, or the sound becomes euphonic, or distortion increases, etc.
After realizing all that, I listened very carefully at the 54.0 (recommended by the factory) and 48.0 settings, and over any other those two settings offer the least amount of distortion, the highest resolution, and the cleanest sound. Everywhere else - if one can train the ear to focus on the right thing - there are a variety of problems, even if subtle; but treble distortion at loud passages is the easiest one to pick up.
Nonetheless, this got me thinking that these settings are integer voltage dividers, and they ought to sound best. The reality is that 54.0 has always sounded clean though euphonic, and now, at 48.0 - and after all of my mods - that setting appears to offer the cleanest, most resolving and less distorted sound, with no euphonic elements to it, and more importantly, the truest timbre and articulation yet. It is quite evident with the better recordings, and especially with HDCD, which shines as a pseudo higher-res option, with real presence and very natural sound when the recording is up for it - e.g. the Janaki Trio Debut
Bottom line: never mind my DAC; the question is how do the various Berkeley Ref series DACs sound at those two volume settings. I need to go back and listen to the Ref3 at 48.0 again, because last time the dealer chose 58.0 and I thought the sound was euphonic and effectively, shit. I am willing to bet that 48.0 on it will also sound the best.
Somewhere in these pages I think, someone said that the Berkeley volume control - going from 0.0 to 60.0 - adjusts in 0.1dB increments. I have been able to verify that with test tones, and more importantly, voltage is halved at -6dB (54.0) and quartered at -12dB (48.0) from the reference; more precisely, based on the same measurements, the drop is respectively -6.0206dB and -12.0412 dB, precisely as it should be - a major engineering feat indeed.
However, as I have posted in the past, digital volume controls frustrate me, even if they don't lose resolution (as is the case with Berkeley DACs). The problem, as I have grappled with over the years, is that tonality changes with various settings, with certain settings sounding elevated in the treble, with others articulation suffers, or bass drops, or the sound becomes euphonic, or distortion increases, etc.
After realizing all that, I listened very carefully at the 54.0 (recommended by the factory) and 48.0 settings, and over any other those two settings offer the least amount of distortion, the highest resolution, and the cleanest sound. Everywhere else - if one can train the ear to focus on the right thing - there are a variety of problems, even if subtle; but treble distortion at loud passages is the easiest one to pick up.
Nonetheless, this got me thinking that these settings are integer voltage dividers, and they ought to sound best. The reality is that 54.0 has always sounded clean though euphonic, and now, at 48.0 - and after all of my mods - that setting appears to offer the cleanest, most resolving and less distorted sound, with no euphonic elements to it, and more importantly, the truest timbre and articulation yet. It is quite evident with the better recordings, and especially with HDCD, which shines as a pseudo higher-res option, with real presence and very natural sound when the recording is up for it - e.g. the Janaki Trio Debut
Bottom line: never mind my DAC; the question is how do the various Berkeley Ref series DACs sound at those two volume settings. I need to go back and listen to the Ref3 at 48.0 again, because last time the dealer chose 58.0 and I thought the sound was euphonic and effectively, shit. I am willing to bet that 48.0 on it will also sound the best.
Don't know how they implement the volume control, but even if it's just resistors, then I've had this DAC for some ten years, and have played with all kinds of volume control settings, so I am tempted to say lack of break-in is not an issue for the sonic differences I am hearing.
Do you mean that a Spectral phono stage was never released, or that you have heard it but that you do not care for it?
If the latter, would you please describe the differences you hear between the Spectral phono stage and the Aesthetix Io?
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