Digital that sounds like analog
- Thread starter opus111
- Start date
Hey Opus...did you happen to see my post on this thread about DG and their ADC equipment for their studios? I believe this was the list of equipment likely used for the recording of Bach you listed by Helene Grimaud. Let us know what you think of it...and how it relates to the sound you heard on that particular recording! Thanks!
Bruce B
WBF Founding Member, Pro Audio Production Member
Its something I tried building a while ago and never got to like the resulting sound. Added to that it needed to be fairly high Q to get a flat response, and tuned around 30kHz. I wonder if the high-ish Q was responsible for my not liking how it sounded? I rather like the multiple DAC solution because its flexible in getting the FR as flat as turns out to be needed - with the high Q peaking stage the FR turns out to be rather sensitive to the precise value of an inductor. The extra DACs help to smooth out bit weight mis-matches in the main DACs too which I reckon will improve low-level linearity.
I looked at the list but there's so much choice there and as Bruce said no particular outboard ADC in evidence. Its really guesswork for what they were using. I have written to 'The Sixteen' based on what I hear on that Brahms recording, we'll see if they respond to my query about which ADC they used.
I must have missed something... The peaking filters I have used were fairly low-Q and peaked right at Nyquist or a little before by design. You only need 3 - 4 dB peak (theoretical droop is 3.54 dB at Nyquist).
Ah perhaps I'm missing something then. I could only get the curve to fit correctly by using the lower slopes of a fairly high-Q peak higher up. I will go back and have another look later, thanks for the heads up.
Another Sviatoslav Richter disc
This one is vintage Richter but only the Rak Preludes sound good - on the second half of the disc, the Etudes Tableaux are washed out rather, lacking dynamics. Looking on the notes I find that the Etudes are 'DDD' from 1988 but the rest are from 1971 and presumably ADD. Score 1 for analog
The preludes here make the disc worth its weight in gold for me, pure magic from the master himself. I want this one on repeat all day long
http://www.amazon.com/Rachmaninov-Preludes-Etudes-Tableaux-Sviatoslav-Richter/dp/B003CP1SRE/
<edit> I wrote the above while only having listened as far as the first prelude. I'll temper my recommendation now in noting that there do seem to be disconcerting variations in level as if some overzealous recording engineer is riding the gain control during the analog recordings.
This one is vintage Richter but only the Rak Preludes sound good - on the second half of the disc, the Etudes Tableaux are washed out rather, lacking dynamics. Looking on the notes I find that the Etudes are 'DDD' from 1988 but the rest are from 1971 and presumably ADD. Score 1 for analog
The preludes here make the disc worth its weight in gold for me, pure magic from the master himself. I want this one on repeat all day long http://www.amazon.com/Rachmaninov-Preludes-Etudes-Tableaux-Sviatoslav-Richter/dp/B003CP1SRE/
<edit> I wrote the above while only having listened as far as the first prelude. I'll temper my recommendation now in noting that there do seem to be disconcerting variations in level as if some overzealous recording engineer is riding the gain control during the analog recordings.
Last edited:
I've built up the stereo pair of LC elliptic filters in differential form now. You'll note that compared to the last filter picture I've changed over to using all small cores now, having listened I couldn't detect any difference in SQ and if I'd used the bigger cores then I'd need to spread the filter over two of these boards - as it is its rather a tight squeeze. Also I'm using a nylon nut now rather than tape to hold the two core halves together. The small board has ferrite beads on to tame filter parasitics - it doesn't act like a low pass filter at very high frequencies (above 2MHz or so) due to stray capacitance across the inductors. However this becomes impossible to model in LTSpice because skin and proximity effects become hugely important at such frequencies and LTSpice does not handle those effects in its models.
This one is vintage Richter but only the Rak Preludes sound good - on the second half of the disc, the Etudes Tableaux are washed out rather, lacking dynamics. Looking on the notes I find that the Etudes are 'DDD' from 1988 but the rest are from 1971 and presumably ADD. Score 1 for analog
http://www.amazon.com/Rachmaninov-Preludes-Etudes-Tableaux-Sviatoslav-Richter/dp/B003CP1SRE/
<edit> I wrote the above while only having listened as far as the first prelude. I'll temper my recommendation now in noting that there do seem to be disconcerting variations in level as if some overzealous recording engineer is riding the gain control during the analog recordings.
This is a great set...well recorded and i've been told one of the best quality recordings of Richter who is well regarded for his Beethoven. That said, tough to find good recordings of Richter...much of it is very hissy. Furtwangler, the German conductor, is similar. Much of his stuff sound like it comes out of a 1940 radio unfortunately...but the music is darned good!
Hi Opus and all,
I am a long time lurker in this forum but have not posted before due to reactions of certain so called objectivists that is prevalent in most audio forum. So it is very refreshing to find a thread devoid of such people. Kudos to you for trying to solve the perennial "achiles heel" of the NOS dac and openly sharing it the public at large. I myself also runs a NOS dac (custom built tube output 1541) and although not very bothered by the droop, will like very much to take your design for a spin once fully developed.
WRT your description of why certain recordings sucked, this could sometimes simply be an issue of polarity. In the wrong polarity, the HF often sounds wrong and diffused. If your system is resolving enough (low noise floor not the super detailed and etched SD type of resolution) and PROVIDED your speaker's tweeters and drivers are wired in the same polarity( both in positive or negative polarity), it is very easy hear polarity in recordings. If your speaker was reviewed in stereophile, in the measurement page under the step response section, it will usually indicate how they are wired.
IME, after certain level of refinement to my system. the biggest improvement came by listening in the correct polarity. In the correct polarity, you will get better soundstage, tonality and timing. It actually affect all frequency range. In stringed instruments, you will hear more of the strings interaction. And the resonance created by strings, piano and brass is easily heard. The effect of the rise and fall massed strings will be dramatic. In the wrong polarity the rising of massed strings will not create the loading effect on the room. You will only hear a louder but flat or hollow sound but will not feel it as you should. In certain very forcefull recordings, as it falls, you will literally feel somewhat like feeling the floor giving way. For vocals, you will hear more of the throat and chest rather than just the mouth. This probably is what you hear that makes the opera so moving. For bass, you will hear it radiate outwards and decay naturally. It will also be fuller. In the wrong polarity the bass will be pinched and often mistaken for tighter bass. For high hats, you will hear the rumble as it settles. In the wrong polarity it will sound diffuse and indefinite. A surprisingly good genre to determine polarity is electronic music as artificial sound effects tend to have good directionality. Winds and atmospheric sounds are weird in the wrong polarity. A good example is brendan perry's this boy from the album ark. In correct polarity (inverted), it will load the room from wall to wall in a solid chunk and the bass will radiate out endlessly. As a guide, blue note, columbia and atlantic are positive or normal and DG, emi and sony are inverted.
I am sorry to have take this thread OT but I hope it helps somewhat to your pursuits. If people are interested, I can discuss more but if not, i will just quietly enjoy this thread.
I am a long time lurker in this forum but have not posted before due to reactions of certain so called objectivists that is prevalent in most audio forum. So it is very refreshing to find a thread devoid of such people. Kudos to you for trying to solve the perennial "achiles heel" of the NOS dac and openly sharing it the public at large. I myself also runs a NOS dac (custom built tube output 1541) and although not very bothered by the droop, will like very much to take your design for a spin once fully developed.
WRT your description of why certain recordings sucked, this could sometimes simply be an issue of polarity. In the wrong polarity, the HF often sounds wrong and diffused. If your system is resolving enough (low noise floor not the super detailed and etched SD type of resolution) and PROVIDED your speaker's tweeters and drivers are wired in the same polarity( both in positive or negative polarity), it is very easy hear polarity in recordings. If your speaker was reviewed in stereophile, in the measurement page under the step response section, it will usually indicate how they are wired.
IME, after certain level of refinement to my system. the biggest improvement came by listening in the correct polarity. In the correct polarity, you will get better soundstage, tonality and timing. It actually affect all frequency range. In stringed instruments, you will hear more of the strings interaction. And the resonance created by strings, piano and brass is easily heard. The effect of the rise and fall massed strings will be dramatic. In the wrong polarity the rising of massed strings will not create the loading effect on the room. You will only hear a louder but flat or hollow sound but will not feel it as you should. In certain very forcefull recordings, as it falls, you will literally feel somewhat like feeling the floor giving way. For vocals, you will hear more of the throat and chest rather than just the mouth. This probably is what you hear that makes the opera so moving. For bass, you will hear it radiate outwards and decay naturally. It will also be fuller. In the wrong polarity the bass will be pinched and often mistaken for tighter bass. For high hats, you will hear the rumble as it settles. In the wrong polarity it will sound diffuse and indefinite. A surprisingly good genre to determine polarity is electronic music as artificial sound effects tend to have good directionality. Winds and atmospheric sounds are weird in the wrong polarity. A good example is brendan perry's this boy from the album ark. In correct polarity (inverted), it will load the room from wall to wall in a solid chunk and the bass will radiate out endlessly. As a guide, blue note, columbia and atlantic are positive or normal and DG, emi and sony are inverted.
I am sorry to have take this thread OT but I hope it helps somewhat to your pursuits. If people are interested, I can discuss more but if not, i will just quietly enjoy this thread.
Threads devoid of an opposing point of view tend to contribute little IMO.
I believe we have a couple of threads discussing polarity; it is an interesting topic. Note what you are describing is phase-matching of the wavefront among all drivers, at the listening position. Because of the crossover networks, achieving that might require the terminals of the drivers themselves be wired opposite of what you might expect. IME speakers that have good impulse response, which requires constant group delay and thus no jumps in phase, provide the best imaging and "clearest" sound for lack of a more objective term.
As for absolute polarity, I have absolutely convinced myself variously that it matters and that it does not through the years. I do try to make sure the impulse response of my system provides the proper absolute polarity (phase), but since (as you said) recordings tend to vary I don't kill myself over it.
I believe we have a couple of threads discussing polarity; it is an interesting topic. Note what you are describing is phase-matching of the wavefront among all drivers, at the listening position. Because of the crossover networks, achieving that might require the terminals of the drivers themselves be wired opposite of what you might expect. IME speakers that have good impulse response, which requires constant group delay and thus no jumps in phase, provide the best imaging and "clearest" sound for lack of a more objective term.
As for absolute polarity, I have absolutely convinced myself variously that it matters and that it does not through the years. I do try to make sure the impulse response of my system provides the proper absolute polarity (phase), but since (as you said) recordings tend to vary I don't kill myself over it.
Hi bbb, a warm welcome and thanks for your thoughts. I shall try invertng the outputs of my DAC and see what I hear. I got it working for the first time - a major lash-up - this morning and can't stop playing CDs on it The biggest change compared to my last DAC (the LAID array of 19 chips) is in the bass - somehow more power and extension. Just an early first impression. Maybe the HF isn't quite as smooth - this could be because the image frequencies aren't being attenuated as well as on the LAID-19. But the tonal colours seem even brighter which I put down to running NOS, the LAID-19 is 2X OS. So its a tradeoff, one I'm happy to make in favour of more colour
What you describe as benefits of correct polarity are the pretty much the same benefits I am getting in reducing noise modulation. Especially the part about hearing more of the body (chest especially) of a person's voice. Yes it is this effect which makes listening to opera so much more emotionally satisfying to me Noise modulation accentuates the HF and makes voices more shrill.
The biggest change compared to my last DAC (the LAID array of 19 chips) is in the bass - somehow more power and extension. Just an early first impression. Maybe the HF isn't quite as smooth - this could be because the image frequencies aren't being attenuated as well as on the LAID-19. But the tonal colours seem even brighter which I put down to running NOS, the LAID-19 is 2X OS. So its a tradeoff, one I'm happy to make in favour of more colour What you describe as benefits of correct polarity are the pretty much the same benefits I am getting in reducing noise modulation. Especially the part about hearing more of the body (chest especially) of a person's voice. Yes it is this effect which makes listening to opera so much more emotionally satisfying to me Noise modulation accentuates the HF and makes voices more shrill.
More sucky digital sound - from Philips this time
A live performance of Beethoven by the revered Alfred Brendel, who I also love dearly. But there's intrusive noise modulation clearly here, blunting the piano leading edges. Not a great example of digital at all, although Brendel's playing is enjoyable.
http://www.amazon.com/Beethoven-Sonatas-E-flat-B-flat-Hammerklavier/dp/B0000041BM/
Explanation found - on the back page of the booklet amongst the recording credits it says this -
'BITSTREAM recording'
That explains it
A live performance of Beethoven by the revered Alfred Brendel, who I also love dearly. But there's intrusive noise modulation clearly here, blunting the piano leading edges. Not a great example of digital at all, although Brendel's playing is enjoyable.
http://www.amazon.com/Beethoven-Sonatas-E-flat-B-flat-Hammerklavier/dp/B0000041BM/
Explanation found - on the back page of the booklet amongst the recording credits it says this -
'BITSTREAM recording'
That explains it
Thank you northstar and gregadd.
Hi Don, yes polarity is closely related to phase in speakers design. IIRC, one is related to direction, the other to time. Although I am not technically schooled, I am aware that due to certain constraints with regards to phase in XO designs, you can't always maintain same polarity in all drivers. All I am saying is that to hear the effects of polarity clearly, it is best to have all drivers in polarity otherwise its a futile attempt. Probably that's why most people don't care much for polarity because getting certain drivers right will inadvertently get other drivers wrong.
Also, when I say devoid, I don't mean devoid of opposing viewpoint. In fact, opposing viewpoint is a must in any discussion of any substance. I am just oppose to the way certain objectivists impose their viewpoint. In any case, I am actually a fan of Don because I actually get to learn stuff. You're the kind of objectivist that we need to have more of. An objectivist who is willing to listen, takes time to carry out test if necessary and if finding the conclusion to be different to convey his thoughts in a nice and thoughtful manner. The usual suspects will just spend hours and hours shouting at people on how stupid and wrong they are without doing anything constructive because so and so or this or that measurements said so.
Hi Opus, maybe you could just build a switch on the dac to flip the polarity or just switch the wires at both speakers as not all recordings are in the same polarity. The key is actually the speaker's drivers polarity. If it is not in the same polarity, it's rather pointless. Oh I forgot earlier that blue note issued by emi in EU is in inverted polarity but blue note USA is normal. Another thing that you might want to experiment is to change your dac grounding wires to silver. Controversial to most, I know, but it won't cost you too much so you might want to give it a go.
Hi Don, yes polarity is closely related to phase in speakers design. IIRC, one is related to direction, the other to time. Although I am not technically schooled, I am aware that due to certain constraints with regards to phase in XO designs, you can't always maintain same polarity in all drivers. All I am saying is that to hear the effects of polarity clearly, it is best to have all drivers in polarity otherwise its a futile attempt. Probably that's why most people don't care much for polarity because getting certain drivers right will inadvertently get other drivers wrong.
Also, when I say devoid, I don't mean devoid of opposing viewpoint. In fact, opposing viewpoint is a must in any discussion of any substance. I am just oppose to the way certain objectivists impose their viewpoint. In any case, I am actually a fan of Don because I actually get to learn stuff. You're the kind of objectivist that we need to have more of. An objectivist who is willing to listen, takes time to carry out test if necessary and if finding the conclusion to be different to convey his thoughts in a nice and thoughtful manner. The usual suspects will just spend hours and hours shouting at people on how stupid and wrong they are without doing anything constructive because so and so or this or that measurements said so.
Hi Opus, maybe you could just build a switch on the dac to flip the polarity or just switch the wires at both speakers as not all recordings are in the same polarity. The key is actually the speaker's drivers polarity. If it is not in the same polarity, it's rather pointless. Oh I forgot earlier that blue note issued by emi in EU is in inverted polarity but blue note USA is normal. Another thing that you might want to experiment is to change your dac grounding wires to silver. Controversial to most, I know, but it won't cost you too much so you might want to give it a go.
I am wondering if the polarity thing has more to it than just the red and black leads to the speakers - that's because amplifier circuitry is never totally symmetrical and I was noticing in a paper only yesterday that noise modulation effects can be provoked more on asymmetrical signals than symmetric. Just a wild notion to follow up in an idle moment. As for trying silver wires - I'd need at least a preliminary hypothesis for why silver might be better than tinned copper - do you have any suggestion as I can't think of one? I usually only do experiments to test falsifiable hypotheses, that's the essence of science.
Funny how this thread is evolving...there are not a lot of switches or whistles/bells on my Zanden DAC...but one of them is a polarity switch. It almost seems like we are taking the same journey that Yamada San may have done in creating his own digital design? In any event, i will spend a little more time with that switch which i tend not to obssess about though i am aware recordings often require you to switch particularly classical as i understand.
It might be a matter of degree. even though it is not perfectly symmetrical, more symmetrical might be better as the more asymmetrical, according to the paper you saw, the easier it is to create more noise modulation distortion.
As to the silver wire, my friend and I have no idea why. it doesn't show up in measurements either. but my friend has built a fair number of dac and we find there is a significant difference. I was just hoping you could shed some light on this as the cost for silver wire for grounding is just a couple of dollars. Not a problem if not.
As to the silver wire, my friend and I have no idea why. it doesn't show up in measurements either. but my friend has built a fair number of dac and we find there is a significant difference. I was just hoping you could shed some light on this as the cost for silver wire for grounding is just a couple of dollars. Not a problem if not.
Similar threads
 | Steve Williams Site Founder | Site Owner | Administrator |  | Ron Resnick Site Co-Owner | Administrator |  | Julian (The Fixer) Website Build | Marketing Managersing |