|Housecleaning - a good summary of my first two assignments for 6moons. One of the dusty corners was the Red Wine Audio/Yamamoto comparison. That was never intended for examination in the bright moon light. The other is the topic of this feature, an ongoing review of the Altmann Attraction DAC. 'Ongoing' here means that I bought the piece for my own personal use. After a time, I learned that it did not mesh perfectly with my TacT preamplifier. I really loved the sonics but knew it could not serve a primary role in my main system absent a significant reworking. Further, it was one of those love pieces that the heart will not allow the intelligent brain to sell.
So I decided to send it out on the road and arranged a group of smart listeners around the country to host tour stops. The overall program included me paying for shipping to the first stop from Seattle to San Diego. It is currently working its way east and has several more layovers, with each host paying shipping to the next stop. It is thus a partnership of sorts and each participant is my partner in spreading the word of what I think is a superb piece of audio engineering and art.
This feature is thus joining the tour in progress. I have checked with my partners in this and I believe all have agreed to make this tour a continuing feature. My initial review and the first stop on the tour are complete and appear below. Neither of these were written understanding the wide audience they would see but future installments will be cognizant of this new expanded forum called Outside on 6moons.
I suppose it should be noted that Charles Altmann is only involved with this feature to the extent that I told him it was happening. At my work we have a favorite expression: "Why reinvent the wheel?" For my contributions here, I'm hoping to expand on the reciprocal question - "why not?"
Original Host Text that kicked off the tour arrangement on AudioCircle
I recently read an interesting essay by our own Srajan Ebaen in the Industry Features section of 6moons. Essentially, it posits there is precious little absolute truth in this hobby. An extension of this observation is that angst, anguish and compromise are more the rule than exception. We are forever questing for betterment and ultimately our own version of perfection, though defining our own personal view of perfection is exceedingly difficult. Knowing how to get there is even harder.
Is the goal flat frequency response? As an owner of a TacT preamp which can make a full-range system flat in-room, I can say flat is generally undesirable. Even our ears do not have flat response, being more sensitive to midrange data at quieter volumes and having flatter response as the volume goes up. Do we tune for quiet or loud volumes? TacT has a variable loudness feature in their newer models to compensate but that is another matter.
Many cry "make it sound like live!" How many recordings have that goal? Compression on nearly all recordings assures the failure of this idea. Should we try to replicate what the engineer heard during the mastering process? Maybe, though I expect most recording monitors would be considered boring by many audiophiles.
Sharing measurements can provide information engineers find useful, but reading Stereophile reviews shows the relationship between measurements and subjective feeling is dubious at best. Subjectivists, me included, inform others to pursue what sounds good. This is a great ideal but breaks down in sharing with others. If someone on an audio forum says "I love this", what does it mean to me? Without knowing preferences, gear and experiences of the writer, there is nothing a reader can use to make their own choices.
Somehow, we decide not only what sound we like but what framework of decision making distills our choices in how to spend our money. I use my own ears and intuition and a few reviewers' opinions and tips. I have a few audio buddies whose ears I trust and their views are important too. Using this haphazard strategy, I have wound up with the following setup:
- Transport: Modwright CDP or Red Wine Audio Squeezebox 3
- Preamp: TacT 2.2XP
- DAC - Altmann Attraction (main array only)
- Main array amplifiers: Yamamoto A-08s or Red Wine Audio Signature 70 monoblocks
- Subwoofer amplifier: Crown K2
- Speakers: Zu Definition Pros
- Cables: various, primarily Zu
The TacT is capable of performing all functions in the digital realm. It has built-in DACs or can send a digital signal for outboard processing. I have always used the built-in DAC for subwoofer duties but have never been satisfied with it for mains duty. My view is that instrumental tone is the cornerstone of quality audio reproduction. Accurate portrayal of dynamic relationships is nearly equal and arguably intrinsic to convincing tone. Both qualities live centrally in the midrange, which I believe is the necessary beginning of great sound.
Much like single-driver, crossover-less speakers, my discovery of battery-powered, non-oversampling DACs with the Red Wine Audio Monica-2 and then the Ack! DAC 2.0 showed me a new way of listening. Focusing more on how the reproduction makes the listener feel instead of how it sounds paves the way for a personal shift. NOS DACs may sound soft around the edges but allow immersion and relaxation where digital reproduction can promote analysis and tension.
I consider the non-oversampling sound to be a move toward holistic presentation and away from audiophile detail. Focus is on lithe transition of notes rather than plucked strings. Much digital is strong with string and weak on wood where my preference is toward decay and tonal richness. Instrumental separation is often touted but digital can remove performers from their proper context in the band and present each separately, supernaturally.
NOS apologists would say that the softness in the treble is better than the disorganized noise characteristic of so much digital gear. Softer transients? A necessary penalty for maintaining singularity of performance. The purely emotional ears can just let this sound wash over, forgetting all the usual audiophilisms.
However, the analytical brain does not rest, asking how the strengths may be maintained while adding the extension and dynamic pop of more conventional solutions. Enter the Altmann Attraction DAC. This is a non-oversampling DAC without a case. Rather, the circuit board is press-fitted into a treated spruce board, said to minimize effects of resonances. It is available with a proprietary jitter-reduction circuit called JISCO and can be upgraded to decode sample rates from RedBook standard of 44.1kHz up to 192.
I used this machine primarily from the digital outputs of my TacT 2.2XP preamp. Somehow, the two did not get along perfectly. The TacT outputs a 24-bit signal whereas the Altmann is a 16-bit machine. Both TacT and Altmann said this should not have mattered but even shipping both units to TacT for a couple of weeks did not cure the problem.
Essentially, the problem was related to a rushing noise at quieter volumes. I was able to listen extensively to the unit at louder volumes, though I sometimes do enjoy my system playing quietly and this was not an effective long-term solution. I was able to use the volume control out of my Red Wine-modded Squeezebox 3 and also used the unit out of a Modwright Music Hall CDP with none of these noise problems.
Without question, the Attraction DAC aligns sonically with the non-oversampling camp. Immediately with the first few notes, it was obvious that this is a piece that quiets the soul and promotes long listening sessions. The lack of 'digital sound' is obvious. This plays out in the performance. Musicians are part of the band, not occupying individual and separate spaces. Second and third harmonics of instruments are clearly portrayed with long and sultry decays. I find the stereotypical digital presentation to be skewed toward the leading edge of the note, such as the plucking of strings and popping of a drumhead. This can be exciting but misses much of the instrument's personality.
|The NOS sound is good at revealing these harmonics but generally worse at the leading edges. Dynamic pop is deemphasized and details are obscured. The Altmann is much better than the NOS average with appropriate sharpness and detail retrieval. Add superb organic flow and this is an intoxicating piece of audio equipment.
Treble response is quite good and struck cymbals have long, shimmering decays. The midrange and upper bass are fantastic with loads of texture, strong leading energy and outstanding harmonics and tone. I cannot comment on deep bass response since my system has powered subwoofers below 65Hz. I hope these comments give some context to my own priorities related to audio and what about this DAC is so (quietly) spectacular to me.
First off Mike Smith really deserves a big thanks for making this audition tour possible. How I got in this queue I don't really remember but I am glad I did. While I do not want to prejudice the following listener, I must say that you guys downstream are going to find this piece most interesting.
I really relished the idea of listening to a piece of audio equipment without having first shelled out the cash for it. No longer would my ears be pressed by the psychology of having made a big purchase. Especially in this case. With the whole DAC exposed on a piece of pine, it gets real easy to make a list of other things you can get for $1K or so. The old scenario of "I just bought this thing so I am going to find out why I like it so much" becomes "I want to buy this thing so I am going to find out why I like it so much". There is a difference.
Of course there is another side to that coin. You can't keep it. You have to unplug it and put your old (old hat) DAC back in. That may turn out to be painful. More on that later. My setup for the audition:
- Maxtor 500 GB HD/PC
- Squeezebox (SB3) modded by RWA running on battery
- Altmann Attraction DAC
- RWA Signature 70s monoblocks
- VMPS RM40s
- Cabling - various - nothing unusual
As is being mentioned in these threads, I had some problems with the whole setup. It actually played off my Squeezebox right of the bat no problem. But after about 10 minutes, things started sounding a little goofy. It sounded like my speakers were clipping - but for no reason. Clipping, when it happens, usually tracks with the dynamics of the piece. Not this time. Eventually it sounded like halfway between two stations on my FM dial.
Those first 10 minutes though were something else. I heard enough in those 10 minutes to want to buy the thing. In a word, what I heard was wetness. Here is another way of expressing it. Going from my Scott Nixon (RWA modded) battery DAC to the Altmann was like going from grape juice to wine. I know those are different metaphors. The idea is that it had a richness and a life that made the Scott Nixon sound a bit dry and wooden.
After some panicky moments (days actually) where I thought I had broken the Altmann and thankfully determined that the battery was the problem, I was back up and running. I was on to evaluation. One thing I learned is that the demo disc which is going to be making the rounds on the audition tour wasn't for me. Not that the music wasn't to my liking. It's that I had to evaluate things with music that I know.
For example, Billy Budd, Benjamin Britten's great opera and one of my favorites, had some moments where massed strings had an incredible solidity and bite that the Nixon only hinted at. Reduced jitter? Probably. Brass ensemble work, trombones especially, started to approach that ringing wave of power that I know from experience. Diana Krall's Tribute to Nat King Cole album, track 7, "Hit That Jive, Jack" features a duet with Diana and someone else. It was only about two stereos ago that I even realized it was a duet. Each improvement to my systems has revealed more. With the Altmann, it was the best yet. Most telling was "Last Rose of Autumn" from The Great Dobro Sessions. Dobro music is great for revealing emotions. That's what all those slides are about. Well, the Altmann was dripping here. It wasn't some tubey sonic signature that I'm talking about. I am talking about Stacy Phillips' dobro playing. Just ridiculously, humanly rich.
There is one demo track that I must comment on. "Keep the Bugs of Your Glass and the Bears off Your Ass" by The Bad Plus (whatever that is). I am guessing this is a demo track for the purposes of demonstrating bass reproduction. Well, the Altmann just smokes the Scott Nixon on the bass lines. It was actually a bit scary. A growling drive I never heard before.
So as I listened for a few days, generally enjoying things, and working out how I was going to pay for the Altmann, something psycho-acoustically very interesting was happening. As time went on, I began to suspect that the Altmann wasn't materially different from my SN. That is, I didn't think I could A/B the two with any reliability at all. Whether that was true or not, I never tested. I wasn't really all that interested in swapping things in and out, back and forth. But as I listened, I couldn't really capture that initial wine vs. grape juice sense. I'm not saying it had left. I just couldn't say for sure that I wasn't hearing things. There were even tracks that had that all too familiar "my $8K stereo still sounds like a Victrola" reaction.
Before I go any further, I must throw in the big caveat on all this: I have a pretty good case of tinnitus. Last time I checked, the music needed to be more than a steady 85dB to drown out the ringing. In fact, I listen to music as much as I do simply as a way to escape tinnitus - not that I listen to it loud enough to drown it out. Tinnitus, obviously, has the undesirable effect of masking many of the details that better music reproduction equipment is supposed to offer. I was well aware as I listened to the Altmann that much of its greatness was being lost on my own damaged ears. But, initially I know I heard some sweet rich music in my living room.
So, how was it putting the Scott Nixon back in? Well, oddly, going the other direction has not been like going forward was. This is partly because the SN modded and on battery power is no slouch. The "Keep the Bugs of Your Glass and the Bears off Your Ass" track clearly showed in an inescapable way where the Altmann comes out on top for certain.
I do have some issues though. The instructions say you need to unplug the power cables from the unit while charging. I see that area as a point of failure. If the connectors for power were to break from all the plugging and unplugging like my laptop's did, it would be most unfortunate. I see it as a likelihood. Why the Altmann hasn't been engineered with a better battery solution à la RWA -- thanks Vinnie -- I don't get. Anyway, thanks again to Mike for his generous offer of this audition tour. I am anxious to hear how it stacks up for others with different equipment down the road.
I just finished up my time with the Altmann today. It is leaving in the morning on its way to the next stop. I would really like to thank Mike for making this tour possible. I enjoyed having the opportunity to hear the Altmann in my system and room for an extended audition. Here goes (insert dramatic pause from first time reviewer). I thought I would start with what's most important to me in audio. Tone. Tone. Tone. Righteous tone - the wail or pluck of a guitar, the attack of piano or brass; getting the notes and beats right; a full range of balanced sound - bass/mid/high; a warm, somewhat liquid sound. Imaging is pretty far down my list but it adds a lot if everything else is right. I know when things are clicking if I'm eager to sit down and listen and reluctant to stop listening.
I started out intending to do a wider comparison by throwing SACD and vinyl into the mix but I ended up mostly comparing the Altmann to the analog outs of my RWA modded Squeezebox 2. Here is the whole system.
- RWA-analog-modded SB2 (with Bolder-modded Elpac power supply) Also the primary digital transport for the Altmann
- Denon DD turntable with DL103 cart
- Toshiba universal player (also tried it as a transport with the Altmann) - lightly modded
- Scott 222c tube integrated amp (rebuilt by HotGlass audio)
- Trends TA-10 (I mostly used the Scott - couldn't tear myself away)
- Parts Express 100wpc plate amp driving the Augies, driven by the Scott's center channel preamp out
- Speakers: Hawthorne Audio Silver Iris Coaxes (running full range) with Hawthorne Audio Augies (crossed over at 50hz, driven by PE plate amp)
- Cables: Bolder digital coax cable, Bolder M80 interconnects, Mapleshade Golden Helix speaker cables to the SI Coaxes, ancient multi strand copper cables to the Augies (15+ years of break-in)
I listened to the following when comparing over the course of a few days and a few moods: Tito Puente Mambo King, Tommy Emmanuel, Allison Krauss, Helloween Keeper of the Seven Keys part 2, Amos Lee, Blue Man Group, Police Ghost in the Machine, Randy Travis Forever and Ever Amen, Jack Johnson Brushfire Fairytales, Metallica And Justice for All and Ride the Lightning, AC/DC Highway to Hell, Eva Cassidy Live at Blues Alley. I used a Radio Shack meter to get a fairly close SPL match.
The Altmann has a much higher output signal than the modded SB2 so it had an easier time driving the Scott and thus the plate amp. The modded SB2 is approximately 1V - not sure what the Altmann kicks out but I'm pretty sure it exceeds the 2V CD spec. I had to turn the level down on the plate amp to balance out the sound with the Altmann in line. The SB2 is a better transport than the Toshiba - at least with the Altmann.
Differences with the Altmann: Cymbals were more natural, both in their tone and the decay of their sound. Soundstage height and depth were increased. It was very very quiet - overall system noise went down a couple of notches for blacker backgrounds etc. Percussion was very nice, transients were sharper and had more impact. Again, nice decay. There was a lot more bass than with the modded SB2, which even after adjusting the plate amp drove the music along very well, giving it a sense of ease (something the Hawthornes do well already at 97dB sensitivity)
Using the Altmann: I used the 44.1 setting with the JISCO on. With Mike's provided charger, using the RatShack battery was easy - easier than vinyl anyway. Definitely a hair shirt type of component. The Altmann was so light I ended up using a weighted tape dispenser (which brand? - not going to tell, you'll have to try your own to see what sounds best) to keep it from turning over due to the weight of the digital coax and interconnect cables.
Summary: Did I like it? Yes, it did a lot of what my modded SB2 does but more. More current, more bass, more drive, more music. It brought a definite analog sound to digital. It was non-fatiguing and I simply enjoyed listening. Is it out of place price-wise in my system? Yes - cost of the Altmann is way more than any of my other components. It is making me rethink the idea of getting a better turntable as my next component purchase though. Would I buy one? Maybe, we'll see how much I miss it when it's not in my system. Did I want to sit down and listen to it? Yes, I made time every night I was home to listen. Did it make me forget about spinning vinyl and just enjoy the ease of digital? Yes, I didn't play much vinyl at all during the audition period. What did my wife think of it? She thought vocals were richer and the bass was fuller. She also thought it was a lot of money for something that looks like that
Side note: Ironically, during the time I had the Altmann, I had to make my first trip ever to Seattle for work so I got to meet the owner of the Altmann and spend some time talking audio with Mike over some of the best salmon I've ever had (alder-planked). The salmon review will be posted separately on AudioCircle. I did order an alder baking plank.
To some degree, I plan on participating in question/answer sessions at AudioNervosa and AudioCircle. I hope the other contributors will do the same. One of my core notions with Outside is to promote as much diversity of opinions and systems as possible. I'd like to promote interactivity. Since it hasn't been done yet in this tied-in fashion with a formal publication, only time will tell whether and how it will work. But, I'm committing to a sincere attempt. Once things are up and running, feedback from readers will be welcome about how to do things better in the future, ask questions about the gear, and so on. Thanks for reading, I hope you like the view from Outside.
First a little bit about my values, goals and objectives in regards to audio reproduction. First and foremost is tonal quality. If the instruments and voices don't sound realistic, it doesn't matter what else the system does well as I can't get past artificial tone. Of course all systems are artificial but many can get the basic tone correct. The next thing that causes me happiness or distress is the high-frequency presentation. This is the area where most digital front ends fail for my tastes. My current digital source is a very heavily modified (analog section) Squeezebox 2. While I like it better than any other digital I've owned and most that I've heard, it pales in comparison to my analog source in this regard. Even good digital sounds pretty lame IMO compared to vinyl.
Source - much modified Slim Devices Squeezebox 2 with gold Bybees
Preamp - none, connected direct to Marchand XM-44 electronic crossover
Amps - mids/highs - R.E. Designs LNPA 150, bass - Rotel 1080
Speakers - Meadowlark Blue Heron 2 modified for active amplification. XO from bass to midrange is at 275Hz, 4th-order LR active, mid/high is at 4kHz, 1st-order passive.
ICs - DIY design using Neotech shielded twisted pair silver cable with the shield connected to ground through a low pass filter
Speaker cables - 10GA twisted pair for bass and Analysis Plus Oval 9 for mid/highs
Power - BPT BP-2.5 Ultra balanced power unit. PCs are assorted DIY stuff. They seem to work well.
During my time with the Altmann, a few friends came over with some additional toys to play with so I had the opportunity to compare the Attraction DAC to a few other devices. My primary comparison was with my much modified SB2, this being one of the first ones modified by Bolder Cable which I have since modified several more times. As I'm friends with Wayne at Bolder, he's been kind enough discuss his mods with me and as I'm a DIY type, I generally do all my own work. My SB2 and power supply are essentially the same as Bolder's top offerings in regards to the analog outputs. My SB2 does not have any of the digital output mods as I don't have a standalone DAC. I used my SB as the digital source for nearly all of my listening with the Altmann. I also had the opportunity to compare it a fairly heavily modified Slim Devices Transporter and a Monica II non oversampling DAC. There is quite a bit about the comparisons to the other devices in this thread.
I listen primarily to Jazz but also have a lot of other music depending on the mood but for this I used pieces I listen to or have heard numerous times. Since I can't get past bad tone, I'll start with that. Tonally, I found the Altmann to be very good, in particular vocals and stringed instruments sounded very good, very rich and full. It was one of the first things I noticed so we were off to a good start. Regarding the bass, I found the Altmann and the SB2 to be very similar. Others have mentioned that the Altmann had better or more extended bass than their Squeezeboxes. In my system this was not the case. Looking at the circuit board, I noticed that the Altmann uses 3.3uF output caps. This is the same value as my SB2 so the -3dB point should be the same.
In the area of high-frequency reproduction, I had the initial impression of less extension in the Altmann but after a while I decided this was not it, the difference was more of a softer HF presentation. I suspect this is a result of the non-oversampling architecture and I can see why people are fond of this. In a less damped room or with aggressive speakers or electronics, I would find this much easier to live with in the long term.
Then there is imaging and spatial presentation. This seems to be an area where there is less agreement on what is important in a system. For me, I enjoy a system where the sounds of the instruments and singers escape the speakers and where it has the ability to present the low-level ambiance cues. For me those low-level cues affect the reality of the presentation even though I know many of them are artificial. I just enjoy the sense of a hall or space. I found the Altmann to do quite well in this area, depending of course on the recording. Interestingly, the SB and the Altmann were somewhat opposite in regards to how the spatial information was presented. On some recordings the Altmann presented layers to the music hat I hadn't heard before but on others, it was closed in while the SB would remove the speakers. The caused me to wonder if there is something in the way the music was encoded that makes it somehow different when decoded by an OS vs Non OS DAC. I don't know of anything that would cause this but it popped into my mind while listening.
In the previously mentioned thread, there is much discussion of running the Altmann on an expensive linear power supply versus a battery. As part of that listening session, Wayne connected a capacitor bank to his SLA and to me it sounded better with the cap bank connected than it did off straight battery but not as good as with the linear supply. As I was still curious about this after Wayne took his toys and went home, I built up a cap bank to use with the Altmann. This consisted of a 15,000uF cap, a 220uF cap and a .1uF cap in parallel along with a switch to connect and disconnect it to the power supply.
I found I preferred the sound with the cap bank engaged. The sound seemed less constrained and more open with the caps turned on. With Mike's permission, I've included this with the travelling DAC so that others can experiment with this as well and hopefully report their thoughts. Did I prefer the Altmann to my SB overall? No, but there are some things I like better about the Attraction, in particular the way is has with vocals and stringed instruments. I could be quite happy with the Altmann but I like by current setup a bit better.
Thanks again to Mike for making this possible. It was great to listen to the Altmann Attraction DAC and I very much enjoyed my time with it and had no desire to remove it from the system. For me that is a very good thing. I've put entirely too many components in the system that make we want to remove them, either immediately or after living with them for a few days. The Altmann never did that and that is a very good thing. Very much worth the time for an audition. I'm sure it will find many fans, I count myself as one.