An inexpensive but good sounding Dac

Danny Richie · « **on:** 18 Jul 2003, 08:21 pm »

Chris Own brought a earlier version of one of these by when he visited last.

http://ack.dhs.org/

It sounded better than it should have for the price.

He says the latest version is even better.

He has been selling quite a few of these. The price is right and he will send out units for demo.

You guys that are interested should try one out, and post some feedback.

He is going to send one down to me in a few weeks for me to try out too.

They are made a little different. You guys check them out.

doug s. · « **Reply #1 on:** 18 Jul 2003, 08:50 pm »

cool, danny, thanks for the link! i wonder how it compares to my modded di/o... also wondering if i could run it from my lab-grade hewlett-packard dc power supply, instead of batteries. i should have an answer soon enuff...

regards,

doug s.

audioengr · « **Reply #2 on:** 19 Jul 2003, 01:32 am »

I have serious doubts as to whether this would outperform a well-designed upsampling DAC. Upsampling allows you to move the filter roll-off and the phase-shift well above the audio range so it's a non-issue. It allows you to get away with low-order filters. I don't experience any lack of dynamics - just the opposite.

nathanm · « **Reply #3 on:** 19 Jul 2003, 03:11 am »

Oooh...I don't need a DAC, but I want this one! Sweet case!

I hope they will come out with the "Thppt!" model soon...

Psychicanimal · « **Reply #4 on:** 19 Jul 2003, 12:30 pm »

Quote from: audioengr

I have serious doubts as to whether this would outperform a well-designed upsampling DAC. Upsampling allows you to move the filter roll-off and the phase-shift well above the audio range so it's a non-issue. It allows you to get away with low-order filters. I don't experience any lack of dynamics - just the opposite.

Quote from: CIAudio

Upsampler... I doubt it for the following reasons:
Although we could probably sell a lot of them.. I haven't heard one that makes an across-the-board sonic improvement. The ones that do, usually have something else going on... jitter reduction, interpolation and higher bit rates (word lengths). The CS8420 is an easy way to do it but introduces alot of trade-offs. There is also rumor of the 8420 being discontinued and maybe the whole Crystal semi division of Cirrus Logic.

This is Dan's opinion from the Modwright forum @ Harmonic Discord:

I have found that straight Redbook, without upsampling, in a good player with the right analog stage is simply fantastic.

OK, who's right here?

nature boy · « **Reply #5 on:** 19 Jul 2003, 12:57 pm »

Danny,

I have a new dAck demo unit on order, should arrive about the same time as the MENSA DI/O audition pack from Wayne. I will try to do an A/B comparison in my system and offer some observations to folks at the Circle. Several inmates who post at Digital Drive (Audio Asylum) swear by the Philips TDA1545T multibit chip and Cirrus Logic CS8414 digital receiver found in the dAck as being the most natural sounding digital processing combination around. I am not going to get into the debate about upsampling vs. non-upsampling, as I just haven't listened to too many DAC's and can't offer an opinion.

The nice thing is there are so many great sounding, reasonable cost DAC solutions to those of us with large Redbook CD collections. With Wayne's audition pack & the $399 dAck ($50 for brand new demonstration - keep it and pay $349 balance) one can do an in home comparison. Just a lot of great options with Scott Nixon's DAD, Rusty Varder's Channel Islands unit (30 return policy) etc.

The dAck unit has rechargable batteries, so like a manual turntable, it requires a bit more user care and maintenance.

Should be a couple weeks before I receive both units.

Here's a link to dAck website in case anyone else is interested in checking this relatively new dAck out - http://ack.dhs.org/.

Nature Boy

Danny Richie · « **Reply #6 on:** 19 Jul 2003, 04:09 pm »

I'll stay out of the debate over which is what and who likes what better.

Just that anytime I feel like someone has something out there that looks to be a really good value I like to pass it on.

Chris is a nice good too, and pretty sharp for a kid.

He's really still in his early 20's I think.

I can't say just how good his latest version is yet, but I think it worth looking at.

Right now I am really happy with Wayne's mods to my D/IO. What a bargain that thing is.

I am sure I will be doing some comparisons too.

audioengr · « **Reply #7 on:** 19 Jul 2003, 04:26 pm »

To give a comparison on upsampling DAC's, I have heard the Meitner/
philips combo extensively. The P-3A upsampling DAC with my mods sounds every bit as good or better. They both upsample however. Most folks that audition either one usually comment on how much it sounds like vinyl, but with increased dynamics.

nature boy · « **Reply #8 on:** 20 Jul 2003, 01:46 pm »

Based on some PM's I have received, we may not only be able to compare the MENSA and Chris Own dAck, but a Stan Warren modified AIWA changer MSB Link combination courtesy of Jack Straw (a regular poster) and a Modwright Level 2 modified Perpetual Technology's P-3A. Looks like my Pioneer PD-65 is going to be in sonic heaven for the better part of an upcoming weekend.

This may however be too much of a good thing to digest is one sitting as my auditory brain functions may overload. I'll have to check with others that have performed shoot-outs to see if we should limit the comparisons to three units. I may also look into get a better transport for the comparison, as the DAC's may simply outclass my old stable platter Pioneer.

More later.

NB

Psychicanimal · « **Reply #9 on:** 20 Jul 2003, 02:54 pm »

Quote from: audioengr

To give a comparison on upsampling DAC's, I have heard the Meitner/
philips combo extensively. The P-3A upsampling DAC with my mods sounds every bit as good or better. They both upsample however. Most folks that audition either one usually comment on how much it sounds like vinyl, but with increased dynamics.

Perhaps you might want to send your unit to Albert Porter and let him post his findings in Audiogon. He can tell us if it really "sounds like vinyl". Would you do that?

Quote from: nature boy

I may also look into get a better transport for the comparison, as the DAC's may simply outclass my old stable platter Pioneer.

Transport is more important than most people reallize. I just switched to a belt driven transport (weighs 23 lbs) and the difference is quite stunning. Belt drive is the way to go. My little Channel Islands DAC is plenty accurate and musical for the job (remember I have serious noise control measures). I am sending the transport to Danny Boy for hot rodding the electronics (I want the bass slam and impact of my top loading McCormack transport), getting the outboard power supply for the DAC and an i2digital cable. I don't think a rig like this needs anything fancier...

Well, I have three Goldmund cones and a non-resonant, Caribbean Moca wood board under the transport--I'm a compulsive tweaker!!!

eric the red · « **Reply #10 on:** 21 Jul 2003, 03:29 pm »

Maybe it's just me, but I seem to remember there being 3-4 more very civil replies on this post that have disappeared since last night? One was from Audio engineer about a demo of his digital rig?

theborg · « **Reply #11 on:** 21 Jul 2003, 03:37 pm »

Look in the Market Square.

audiojerry · « **Reply #12 on:** 21 Jul 2003, 03:56 pm »

I also agree that the quality of the transport has a significant influence on sound quality. I recently acquired a dedicated transport from Classe after having used a very good Classe cdp as a transport for my P-3A, and the improvement in sound was easily noticed.

On upsampling, I believe that Audio Research Corp. has excellent R&D, and they did a lot of research before finally deciding that upsampling/oversampling is not a panacea, and it does not represent an instant improvement. Their reference cd player, CD-3 ($4995) does not upsample. I listened to it in a friend's system, and I believe it sounds outstanding, but I've never compared it directly to my own in my system. Then again, no way would I pay that much for my cd playback system.

eico1 · « **Reply #13 on:** 21 Jul 2003, 04:38 pm »

The cd-3 may not upsample, but like most cd players it does use oversampling. I believe you can disable the upsampling in the p-3a though.

steve

audiojerry · « **Reply #14 on:** 21 Jul 2003, 06:53 pm »

Quote from: eico1

The cd-3 may not upsample, but like most cd players it does use oversampling.

If the CD-3 oversamples, I didn't see ARC mention it in its website specs. Usually, if oversampling is done, it is defined as being 4x, or 8x oversampling, or something like that.

eico1 · « **Reply #15 on:** 21 Jul 2003, 10:09 pm »

aj, ARC claim to use the latest Crystal dacs which are delta-sigma types. Check those data sheets. If they meant no oversampling, they probably would have mentioned it is also a digital filter-less design.

steve