Pricklely Peete
Franken modder
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Mini - Review Part II Zero DAC - Analog Output Section - HDAM vs OPA627BP
Preface....
To start I'd like to thank those that have supplied information, guidance and advice in this huge Zero thread to which I hope to contribute yet another option for those willing to experiment
I've spent many hours of late giving equal time to the objects in question, in hopes of giving either method of choice, for your Zero, an exhaustive series of sound quality evaluations. The intent of the reveiw is to disect the attributes of each approach, it's advantages vs cost and sound quality in the Zero DAC analog section only.
I have decided to use my main rig for the listening sessions (in Part II) since it's resolution makes my job that much easier.
With that out of the way here is the list of related gear for the test.......
Source -
JVC XL-FA92 DVD-A (7 disc changer) digital coax output via silver serpant .5m -----> Zero coax input -----> Musical Fidelity X-10D V3 + X-PSU (PF mod) -----> MIT 330 Series III 2.5 m cable -----> Preamp - Meixing MC-7R pre (RCA 5751 x 2, RCA 12AU7 cleartops x 2, RCA Jan 5U4G rectifier x 1 ) ----- > MIT 330 Series II 2.5 m cable ------->
Analog Crossover (active) -
Marchand 3 way crossover ----> MIT 330 Series II 2.5 m ----> 125 HZ High Pass ouput to midrange and ribbon tweeter panels on main speakers, 50 HZ High Pass to bass driver on main speakers, Variable Low Pass set at 60 HZ - to stereo subs. All xover slopes are 2nd order except sub. Sub is 4 th order Linkwitz Reily.
Power Amps -
Meixing MC34-AB all tube stereo power amp, Sylvania black plate 5965-12AT7 sub x 2, Sylvania 6SN7 GTB chrome domes - 50's vinatge x 2, Jinvina Blue Glass EL34 x 8 *. Dual mono with outboard PS transformers in a "Power Humpty" config connected to main chassis by heavy duty screw terminal cables. Handles ouput from Crossover for mid/tweeter on main speakers.
* Rated at 75 w/channel ultralinear (grossly underated power output IMO) 40 w/channel triode.
Odyssey Stratos with 120K filter cap upgrade- Solid state 150 w/channel stereo. Takes 50 HZ high pass from Crossover to bass driver on main speakers.
CDP - Source **
Ah Njoe Tjoeb 4000 with all upgrades except super clock. Modified with Mil spec Russian PIO bypass caps in PSU and Analog output. NOS Tesla Mil Spec gold pin 6922 x 2. Nordost Blue Heaven .6m to pre.
** used in last part of reveiw head to head against other source (stack) for comparison.
TT, Cassette Deck, Tube phono amp- not used in test.
Main Speakers
Eminent Technology LFT-VIIIB - hybrid planar/ribbon tweeter/dynamic 8" woofer. Bi amped with Nordost Blue Heaven II speaker cable (double run not bi wire) banana plugs x 2. Edison price binding posts on ET speakers. Internal crossover first order on mid/hi panel, 2 order on bass driver.
Stereo Subs + Active digital eq (the secret weapon
Behringer Feedback Destroyer Pro *** set for dual channel digital parametric eq ). Dayton Audio 12" Titanic II drivers w/500 watt mono plate amp (top of line type from Dayton) in 3 cubic foot MDF cabs x 2. Stacked in corner of room as a tower. 2ft clearance from side and back wall.
*** Time aligned (crudely) and painstakingly EQ'd to ameliorate room anomalies. It is acting on signal below 60 HZ only from Marchand Xover stereo sub outputs.
Cabling from pre to Xover to Amps - MIT, Xover to Behringer- Silver serpant RCAs, Behringer to Subs - Dayton audio sub cable 4 m each.
Yikes, wiring and set up of this monster is a PITA. Not to mention powering it all. Ran dedicated (installed by myself...pretty damn easy really) 20 amp lines x 2 to 4- ACME 20 amp receptacles (gold plated and cryo'd ) via plain old but heavy as hell 10 gauge solid core Romex 10/2 w ground.
On to the results....
Rather than list the source music.... this test period ran the same CD's from first part (part I). If you don't recall what those were please take a few minutes to look at Part I farther back in the Zero thread. Thanks for your attention so far. I know it's quite a bit of gear to read through, but I'm convinced that knowing the equip used for the test is crucial for the reader to know.
Zero - BB OPA627BP
First up we have the brown dog adapter with 2 OPA627BP chips installed in the Zero's Analog DAC section. Alowed 2 hours warm up (because of the tube gear) playing test rotation of music.
During opening cut of DT disc, the ambience and tolling bell seemed to envelope me from 2 sides ( more like 180 degrees ) . Great image projection from side to side, with the speakers almost dissappearing. It seemed that the image would alternate between narrow and wide throughout this CD. I'm not sure what the mixdown engineer was trying to accomplish on this disc. Still, to be able to critique that mix in the first place is a sign of the SQ edge the OPA627's give the Zero.
Similar characteristics are exihitbed by the OPA627 as what I would call the BurrBrown house sound. With the change from the Zero head amp to the analog outs in Part II, the cymbal work has lost some of it's whitish metallic edge. Although it's still present it's reduced which is a welcome addition. Considering the Zero head amp section is a throw in, it does a credible job especially when the stock opamps are swapped for the well known LT1364s. Hats off to Lawrence for including this quality "throw in" to the Zero. Bass is solid, somewhat polite but rendered with truth of timbre.Tonal spectrum is recessed slightly in upper mids with a roll off in the extreme highs. Typical BB characteristics observed in Part I. The level of this recess is less so when straight out from the Zero's analog outputs. Nice. On the Gladiator Sound Track Lisa's voice lost it's slight sibilant quality noticed when using the Zero HA stage. Strings soar above brass instruments, SFX come through with clarity, percussion has nice solid foundation and transient speed. Slightly polite rendition once again, but not ragged or hard. Instrument overtones can be picked out although not without some concentration in complex passages. A compression of crescendos is still noticed. We are talking about compressing the dynamics by a slight amount. If you have a HDAM you'll be able to notice this fairly easily, without the HDAM you may not notice it at all. The polite bass actually helps this CD since it's overdone to begin with. Imaging is very good, another 627 strength, with solid placement and plenty of space around the instrument. Hall ambiance and delay echoes trail off into the distance with realism. Very good overall in this respect. I did notice a tendency to cut them short if hit with a sudden increase in complexity and volume. Not a big deal IMO but worth mentioning.
On the Musical Fidelity Sound Lab's remaster of U2's The Joshua Tree one can't help but notice the really poor quality of the bass guitar's tracks. It's fat, bloated, sounds like a 50 dollar Fender Precision knock off being amped through a crappy SUN amp with blown speakers and worn out tubes. I don't know why the engineers recorded the bass this way. Of course this level of insight into the oddly recorded bass is laid bare by the 627 and due to it's polite nature in this region helped mitigate that flaw somewhat (IMHO it's a major drawback to the album as a whole). I think it was Daniel Lanois's first recording as sound engineer with U2 ( I could be wrong about that). Steve Lillywhite had been the engineer on the precceeding effort "The Unforgettable Fire" IIRC. With that caveat the rest of the album's instruments and especially Bono's Vox are exceptionally done. MFSL have done a fantastic job restoring the edge's jangle without overshadowing Bono's rasp. The 627's allow a perfect window into this passionate interplay. What a great vocalist he was ( he can no longer maintain that vocal style IMO, it takes incredible effort and youth ). It's a fairly simple album without tons of overdubs and that can be a blessing. I noticed much less compression with this CD on complex passages. Interesting......
The 627 does a great job with this difficult recording managing to present it as a whole while hi-lighting the individuals without much alteration or fan fare.
I have to say once again the 627 is a quality opamp maybe the best ever made (so far) and continues to be the Deusenburg (SP ?) gold plate standard for playback SQ. Others will disagree with this statement, that's just fine...it's all subjective after all
It sure does a fine job on the main rig !!!
It's been a difficult process to arrive at since Part I covered many of the traits the 627 has and have in Part II. What I'd like to talk about now is the level of these traits between test configs. The latter test has been much more difficult to notice these drawbacks due to the Zero's HA section being removed from the playback loop. In a nutshell the 627 does have a polite nature, recessed hi mid, and rolled of highs, a slight metallic edge on cymbals,bells, etc....but it also renders voice,stringed instruments, synths, percussion with startling realism and truth of timbre. I've purposely focussed on these attributes in hopes of painting a picture between what the 627 does or doesn't do and what the HDAM does (there isn't a doesn't do with the HDAM as I have found out).
I know this is a long (mini) review, thanks for not falling asleep or jumping to another post. I promise it won't be much longer....(famous last words)
Zero - HDAM Module
Once everything was powered back up and left to settle for a 2 hour period before listening I couldn't help but notice, that during the warm up period as music was playing (85 db) the dynamic scale of the music seemed immediately larger.......kind of caught me off guard a little. So I grabbed a coffee and sat out on the deck letting the warm up period pass without listening further and trying to clear my memory through a little meditation. Well that time period flew by rather quickly and downstairs I went, refreshed, full of caffeine and ready to listen
Same rotation of music in random order this time around.
DT CD six degrees of turbulence - The dynamics of the Cd are apparent from the get go, like a gut punch the kick drum hammers away, snare has it's unique snap and decay, cymbals sound real, hi hat is easily discernible. Cymbals from ride to crash to splash all have the correct tone, decay, and transient impact. A cymbal is both lightning fast and slow at the same time. A very difficult sound to reproduce. The HDAM does a commendable job on these, best I've heard so far, but alas it does not have the last ounce of realism. I think that may have to do with the DAC as a whole rather than the HDAM itself. That analogy also takes into account the 627. To what degree can the Zero be upgraded to squeeze more out of it is an exercise in an upcoming article . Needless to say I think even more can be squeezed from the Zero for little outlay of cash !!! What needs to be said time and time again, and I'm guilty of this, is the fact that this DAC is a bargain basement budget piece of kit. Spending wads of cash on boutique PIO film caps, expensive resistors and such is kind of defeating the point.
With that "hey buddy get your head out of the clouds" its a 150 dollar DAC how can it be any damn good at all and why would you spend 80 bucks on a HDAM. Cause it's sounds great,flat out toe tapping, big stupid grin, musical, expansive....great
. I love listening to DT on this rig......
Petrucci is one hell of great guitarist, not for his blinding speed but his ability (like Jeff Becks) to get the instrument to sing. If you've ever played electric guitar you'll know what I'm talking about. For those who don't know I'll attempt to explain. Certain areas on the neck of a well made guitar, the notes, if played with great finesse, will combine both fundamental and harmonic with the first harmonic becoming dominant through controlled feedback with the amp, vibrato technique of the player and careful manipulation of the guitars volume and tone control knobs. The absolute beauty of this type of playing (melodic single note run ) is Beck's hallmark and Petrucci's to a lesser extent. The HDAM allows this beauty to be fully explored and enjoyed. I could listen to Beck until my ears bleed
Jeff Beck and Jan Hammer Live is another great listen ....The 627 for the most part portrays this delicate interplay between artist and instrument but not at the level the HDAM does. I'm impressed every time I listen to this cut ( Misunderstood) and try to get past it without hitting replay.
It just seems so relaxed yet muscular at the same time. Transient speed is outstanding as is SNR. Simply put I won't listen to DT without the HDAM installed in the Zero. The Zero/HDAM is only bested by my modified Ah NJoe Tjoeb 4000. Only after I modified the Tjoeb could I say that with conviction. You could buy 2 Zero's with HDAM for just the upsampler unit in the Tjoeb. Again I have to pinch myself, it's only 150 + 80.........the Tjoeb is 1600.00 with all options and then some.
Here are some of the observations from my listening notes over the last 3 weeks.......lightning fast transients, unrestrained dynamics, huge 3D image, no compression of complex passages, layering of track's recording easily discerned yet presents track as coherent musical whole. Bass delivered without emphasis or color. Mids have bite when called upon yet are liquid smooth, highs are presented with no artificial sheen or metallic edge, what is on the disc comes across as recorded. Makes you forget the details and enjoy the immersive nature of the experience. That last thought is what makes it for me, out of all the other attributes, if it doesn't sweep you away to another place then what's the point of listening in the first place ? The HDAM and to a slightly lesser degree the 627 allow me to enjoy the music for what it is.
CONCLUSION.......finally
Before you jump to the conclusion that I'm over hyping a 200 dollar DAC bear this in mind. To me a monetary value only tells one part of the story. The real value of anything is in it's enjoyment, it's ability to scale with modifications and add on options.....on this front the Zero delivers in spades whether you choose the OPA627 in the DAC section or the outstanding HDAM module. I think back to when digital meant LED watches that cost 1000 US when they first came out....
35 years ago 250 US wouldn't buy you jack squat in audio other than a piece of junk.
Thank god for the Chinese, long live Chinese Audio
Peete.
Preface....
To start I'd like to thank those that have supplied information, guidance and advice in this huge Zero thread to which I hope to contribute yet another option for those willing to experiment
I've spent many hours of late giving equal time to the objects in question, in hopes of giving either method of choice, for your Zero, an exhaustive series of sound quality evaluations. The intent of the reveiw is to disect the attributes of each approach, it's advantages vs cost and sound quality in the Zero DAC analog section only.
I have decided to use my main rig for the listening sessions (in Part II) since it's resolution makes my job that much easier.
With that out of the way here is the list of related gear for the test.......
Source -
JVC XL-FA92 DVD-A (7 disc changer) digital coax output via silver serpant .5m -----> Zero coax input -----> Musical Fidelity X-10D V3 + X-PSU (PF mod) -----> MIT 330 Series III 2.5 m cable -----> Preamp - Meixing MC-7R pre (RCA 5751 x 2, RCA 12AU7 cleartops x 2, RCA Jan 5U4G rectifier x 1 ) ----- > MIT 330 Series II 2.5 m cable ------->
Analog Crossover (active) -
Marchand 3 way crossover ----> MIT 330 Series II 2.5 m ----> 125 HZ High Pass ouput to midrange and ribbon tweeter panels on main speakers, 50 HZ High Pass to bass driver on main speakers, Variable Low Pass set at 60 HZ - to stereo subs. All xover slopes are 2nd order except sub. Sub is 4 th order Linkwitz Reily.
Power Amps -
Meixing MC34-AB all tube stereo power amp, Sylvania black plate 5965-12AT7 sub x 2, Sylvania 6SN7 GTB chrome domes - 50's vinatge x 2, Jinvina Blue Glass EL34 x 8 *. Dual mono with outboard PS transformers in a "Power Humpty" config connected to main chassis by heavy duty screw terminal cables. Handles ouput from Crossover for mid/tweeter on main speakers.
* Rated at 75 w/channel ultralinear (grossly underated power output IMO) 40 w/channel triode.
Odyssey Stratos with 120K filter cap upgrade- Solid state 150 w/channel stereo. Takes 50 HZ high pass from Crossover to bass driver on main speakers.
CDP - Source **
Ah Njoe Tjoeb 4000 with all upgrades except super clock. Modified with Mil spec Russian PIO bypass caps in PSU and Analog output. NOS Tesla Mil Spec gold pin 6922 x 2. Nordost Blue Heaven .6m to pre.
** used in last part of reveiw head to head against other source (stack) for comparison.
TT, Cassette Deck, Tube phono amp- not used in test.
Main Speakers
Eminent Technology LFT-VIIIB - hybrid planar/ribbon tweeter/dynamic 8" woofer. Bi amped with Nordost Blue Heaven II speaker cable (double run not bi wire) banana plugs x 2. Edison price binding posts on ET speakers. Internal crossover first order on mid/hi panel, 2 order on bass driver.
Stereo Subs + Active digital eq (the secret weapon
*** Time aligned (crudely) and painstakingly EQ'd to ameliorate room anomalies. It is acting on signal below 60 HZ only from Marchand Xover stereo sub outputs.
Cabling from pre to Xover to Amps - MIT, Xover to Behringer- Silver serpant RCAs, Behringer to Subs - Dayton audio sub cable 4 m each.
Yikes, wiring and set up of this monster is a PITA. Not to mention powering it all. Ran dedicated (installed by myself...pretty damn easy really) 20 amp lines x 2 to 4- ACME 20 amp receptacles (gold plated and cryo'd ) via plain old but heavy as hell 10 gauge solid core Romex 10/2 w ground.
On to the results....
Rather than list the source music.... this test period ran the same CD's from first part (part I). If you don't recall what those were please take a few minutes to look at Part I farther back in the Zero thread. Thanks for your attention so far. I know it's quite a bit of gear to read through, but I'm convinced that knowing the equip used for the test is crucial for the reader to know.
Zero - BB OPA627BP
First up we have the brown dog adapter with 2 OPA627BP chips installed in the Zero's Analog DAC section. Alowed 2 hours warm up (because of the tube gear) playing test rotation of music.
During opening cut of DT disc, the ambience and tolling bell seemed to envelope me from 2 sides ( more like 180 degrees ) . Great image projection from side to side, with the speakers almost dissappearing. It seemed that the image would alternate between narrow and wide throughout this CD. I'm not sure what the mixdown engineer was trying to accomplish on this disc. Still, to be able to critique that mix in the first place is a sign of the SQ edge the OPA627's give the Zero.
Similar characteristics are exihitbed by the OPA627 as what I would call the BurrBrown house sound. With the change from the Zero head amp to the analog outs in Part II, the cymbal work has lost some of it's whitish metallic edge. Although it's still present it's reduced which is a welcome addition. Considering the Zero head amp section is a throw in, it does a credible job especially when the stock opamps are swapped for the well known LT1364s. Hats off to Lawrence for including this quality "throw in" to the Zero. Bass is solid, somewhat polite but rendered with truth of timbre.Tonal spectrum is recessed slightly in upper mids with a roll off in the extreme highs. Typical BB characteristics observed in Part I. The level of this recess is less so when straight out from the Zero's analog outputs. Nice. On the Gladiator Sound Track Lisa's voice lost it's slight sibilant quality noticed when using the Zero HA stage. Strings soar above brass instruments, SFX come through with clarity, percussion has nice solid foundation and transient speed. Slightly polite rendition once again, but not ragged or hard. Instrument overtones can be picked out although not without some concentration in complex passages. A compression of crescendos is still noticed. We are talking about compressing the dynamics by a slight amount. If you have a HDAM you'll be able to notice this fairly easily, without the HDAM you may not notice it at all. The polite bass actually helps this CD since it's overdone to begin with. Imaging is very good, another 627 strength, with solid placement and plenty of space around the instrument. Hall ambiance and delay echoes trail off into the distance with realism. Very good overall in this respect. I did notice a tendency to cut them short if hit with a sudden increase in complexity and volume. Not a big deal IMO but worth mentioning.
On the Musical Fidelity Sound Lab's remaster of U2's The Joshua Tree one can't help but notice the really poor quality of the bass guitar's tracks. It's fat, bloated, sounds like a 50 dollar Fender Precision knock off being amped through a crappy SUN amp with blown speakers and worn out tubes. I don't know why the engineers recorded the bass this way. Of course this level of insight into the oddly recorded bass is laid bare by the 627 and due to it's polite nature in this region helped mitigate that flaw somewhat (IMHO it's a major drawback to the album as a whole). I think it was Daniel Lanois's first recording as sound engineer with U2 ( I could be wrong about that). Steve Lillywhite had been the engineer on the precceeding effort "The Unforgettable Fire" IIRC. With that caveat the rest of the album's instruments and especially Bono's Vox are exceptionally done. MFSL have done a fantastic job restoring the edge's jangle without overshadowing Bono's rasp. The 627's allow a perfect window into this passionate interplay. What a great vocalist he was ( he can no longer maintain that vocal style IMO, it takes incredible effort and youth ). It's a fairly simple album without tons of overdubs and that can be a blessing. I noticed much less compression with this CD on complex passages. Interesting......
The 627 does a great job with this difficult recording managing to present it as a whole while hi-lighting the individuals without much alteration or fan fare.
I have to say once again the 627 is a quality opamp maybe the best ever made (so far) and continues to be the Deusenburg (SP ?) gold plate standard for playback SQ. Others will disagree with this statement, that's just fine...it's all subjective after all
It's been a difficult process to arrive at since Part I covered many of the traits the 627 has and have in Part II. What I'd like to talk about now is the level of these traits between test configs. The latter test has been much more difficult to notice these drawbacks due to the Zero's HA section being removed from the playback loop. In a nutshell the 627 does have a polite nature, recessed hi mid, and rolled of highs, a slight metallic edge on cymbals,bells, etc....but it also renders voice,stringed instruments, synths, percussion with startling realism and truth of timbre. I've purposely focussed on these attributes in hopes of painting a picture between what the 627 does or doesn't do and what the HDAM does (there isn't a doesn't do with the HDAM as I have found out).
I know this is a long (mini) review, thanks for not falling asleep or jumping to another post. I promise it won't be much longer....(famous last words)
Zero - HDAM Module
Once everything was powered back up and left to settle for a 2 hour period before listening I couldn't help but notice, that during the warm up period as music was playing (85 db) the dynamic scale of the music seemed immediately larger.......kind of caught me off guard a little. So I grabbed a coffee and sat out on the deck letting the warm up period pass without listening further and trying to clear my memory through a little meditation. Well that time period flew by rather quickly and downstairs I went, refreshed, full of caffeine and ready to listen
DT CD six degrees of turbulence - The dynamics of the Cd are apparent from the get go, like a gut punch the kick drum hammers away, snare has it's unique snap and decay, cymbals sound real, hi hat is easily discernible. Cymbals from ride to crash to splash all have the correct tone, decay, and transient impact. A cymbal is both lightning fast and slow at the same time. A very difficult sound to reproduce. The HDAM does a commendable job on these, best I've heard so far, but alas it does not have the last ounce of realism. I think that may have to do with the DAC as a whole rather than the HDAM itself. That analogy also takes into account the 627. To what degree can the Zero be upgraded to squeeze more out of it is an exercise in an upcoming article . Needless to say I think even more can be squeezed from the Zero for little outlay of cash !!! What needs to be said time and time again, and I'm guilty of this, is the fact that this DAC is a bargain basement budget piece of kit. Spending wads of cash on boutique PIO film caps, expensive resistors and such is kind of defeating the point.
With that "hey buddy get your head out of the clouds" its a 150 dollar DAC how can it be any damn good at all and why would you spend 80 bucks on a HDAM. Cause it's sounds great,flat out toe tapping, big stupid grin, musical, expansive....great
Petrucci is one hell of great guitarist, not for his blinding speed but his ability (like Jeff Becks) to get the instrument to sing. If you've ever played electric guitar you'll know what I'm talking about. For those who don't know I'll attempt to explain. Certain areas on the neck of a well made guitar, the notes, if played with great finesse, will combine both fundamental and harmonic with the first harmonic becoming dominant through controlled feedback with the amp, vibrato technique of the player and careful manipulation of the guitars volume and tone control knobs. The absolute beauty of this type of playing (melodic single note run ) is Beck's hallmark and Petrucci's to a lesser extent. The HDAM allows this beauty to be fully explored and enjoyed. I could listen to Beck until my ears bleed
Here are some of the observations from my listening notes over the last 3 weeks.......lightning fast transients, unrestrained dynamics, huge 3D image, no compression of complex passages, layering of track's recording easily discerned yet presents track as coherent musical whole. Bass delivered without emphasis or color. Mids have bite when called upon yet are liquid smooth, highs are presented with no artificial sheen or metallic edge, what is on the disc comes across as recorded. Makes you forget the details and enjoy the immersive nature of the experience. That last thought is what makes it for me, out of all the other attributes, if it doesn't sweep you away to another place then what's the point of listening in the first place ? The HDAM and to a slightly lesser degree the 627 allow me to enjoy the music for what it is.
CONCLUSION.......finally
Before you jump to the conclusion that I'm over hyping a 200 dollar DAC bear this in mind. To me a monetary value only tells one part of the story. The real value of anything is in it's enjoyment, it's ability to scale with modifications and add on options.....on this front the Zero delivers in spades whether you choose the OPA627 in the DAC section or the outstanding HDAM module. I think back to when digital meant LED watches that cost 1000 US when they first came out....
35 years ago 250 US wouldn't buy you jack squat in audio other than a piece of junk.
Thank god for the Chinese, long live Chinese Audio
Peete.
