Keith_W system

[Keith_W]

Hi guys, thanks for dropping in. My system is a work in progress. This is what it looked like as of last month:

When I started, it was a fairly conventional source - preamp - power amp - speaker system. As you can see, it has been converted to run active, with each driver having its own power amplifier. The reason I made all these changes is because the horns and tweeter never sounded as if they were tied in with the bass driver.

You may also note that the upper frequencies are handled by the Marchand (an active analog crossover) with the bass handled by a DEQX. Why not use the DEQX for the whole system? This is where I become a subjectivist - I can't tell you why the DEQX sounds worse, it just does. I think it has something to do with the analog to digital conversion that sucks the life out of the sound. Dynamics sound compressed, and music sounds limp and uninvolving. However, it DOES bring with it some benefits - once the drivers are time aligned and driver and room correction applied, the sound has a coherence that the analog crossover can't match.

For a few years now I have had to choose which compromise I was willing to accept. Use the DEQX full time but get limp, lifeless sound? Or live with a less coherent system with the Marchand not being able to perform DSP?

In the end, I settled for the Marchand handling the high frequencies, with the DEQX performing bass correction duties for the subwoofer only. This still has drawbacks, the most serious being the 20ms processing overhead that the DEQX introduces with respect to the Marchand. This exacerbates the time delay of the subwoofers, which is already time delayed compared to the main system.

So it was with great interest that I read Blizzard's contribution in WBF nearly a year ago: http://www.whatsbestforum.com/showthread.php?18648-The-best-way-possible-to-build-an-active-system

In it, Blizzard suggested a computer based crossover using a multi-channel NADAC DAC for output directly to some power amps. All I would have to do is to build a PC and purchase enough DAC's for output. I spent some months reading up as much as I could on computer audio and Acourate. It also helped a great deal when WBF member (who also lives down the road from me) Trevor came over with his friend Aris and demonstrated Acourate on my system.

It is a cliche to say that I was blown away, but this was one of the big eye opening moments in my hifi journey. They brought over a little Raspberry Pi, and took a rough measurement of my system. Aris loaded the filter into the Pi, and away they went. With my own MPS-5 performing the DA conversion, I could not believe how coherent the system sounded. Even with this modest hardware (and albeit not having an ADC step and using a much superior DAC), it left the DEQX in the shade.

The little Raspberry was struggling to perform on the fly conversion. From time to time it would hiccup. Aris assured me that if I had a more powerful PC, and if I let Acourate perform the crossover function and thus have even more control of my system, I would get even more of a benefit.

So now I was fully convinced. One month ago, I finally bought all the parts required and now my system looks like this:

Now the PC is the source, and I am using my Playback Designs MPS-5 as a DAC. I would prefer to use the MPS-5 as a transport, however it is not possible to use the optical drive as a transport AND get it to perform D-A conversion at the same time. To get me up and running, I am using the optical drive on the PC as a transport.

Eventually I will switch to using files stored in the PC's SSD as the source, but given that I have more than 4000 CD's, of which only half have been ripped, this isn't going to happen any time soon. For now and the immediate future, I will still need an optical drive. My hobby is listening to music, not sitting in front of my computer for hours upon hours for weeks on end mindlessly feeding CD's for ripping!

For those curious about the PC, this is the recipe:

CPU: Intel i7-6700K
Mobo: MSI B150I Gaming Pro Mini-ITX
RAM: Corsair Vengeance 2133 2x 8GB
Storage: Samsung 850 Evo 1TB SSD
Case: Streacom FC10 Alpha fanless (capable of dissipating the 95W TDP the i7-6700K produces)

Other:
- RME HDSPe AES sound card
- Dell S2240T touch screen monitor

Software:
- Windows 10 Home edition
- Acourate (to generate filters)
- HQPlayer (to upsample and perform convolution)

After I gathered all the hardware together and purchased all the licenses, I eagerly fired up the system when BANG one of the power amps decides to let out the magic smoke. As of right now I am twiddling my thumbs, waiting for the power amp to be repaired before I can get started taking measurements and generating DSP filters. Hopefully the power amp will return this week and I can finally get started.

I bought a HQPlayer license because HQPlayer is able to generate crossovers directly, apply Acourate generated convolution filters, and upsample to quad DSD. According to others, it sounds superior to on-chip upsampling. I can't tell you either way myself, I have the license but I haven't listened to it yet!

You may also notice that there is a new subwoofer in there. I bought four Rythmik Audio 12" drivers and I am getting a local speaker designer to build and test the sub for me. This should also hopefully be an improvement over the JL Audio F110's.

In the future, the PC will become a fully functional crossover. I have yet to decide on which multi-channel DAC to buy, but at this stage it will probably be the Merging+ NADAC.

At the moment, I am not sure how I would take measurements once the NADAC is purchased and the crossover is implemented. I am currently discussing this with the author of Acourate, Dr. Uli Brueggemann on the Acourate forum.

 

[amirm]

I have more to say later but boy, have you set a high bar in creating such threads! Diagrams and all. I have my work cut out for me when I do mine.

 

[fas42]

Interesting your experiences with the DEQX ... a local chap has done many rounds in getting his unit to present better quality sound, he actually killed it at one stage by doing internal mod's - even now, as I noted in one listening session, when it started from cold that the sound was lacking, until it suddenly snapped into shape right in the middle of a track.

Apparently the latest versions are much better, but I have no experience of them ...

 

[Sal1950]

Great post Keith W, no way I could compete with your graphics, or system for that matter. But thanks for sharing and charting your path to the current place. I enjoy the insight into our fellow members gear, great or modest..
My work in progress post along with a couple other members is here,
http://audiosciencereview.com/forum/index.php?threads/the-kit-we-bought-our-current-setups.564/
il saluto

 

[Thomas savage]

This is a great path you have taken imo, expertly communicated too. To me it's the logical way to go, beyond question.

Your taking full advantage of digital audio, and why not!

Brilliant .

 

[Keith_W]

Thank you gents. The diagrams are necessary, because if I were to attempt to explain it in words, it might be rather difficult to read.

Right now I don't know how to take measurements of the system once the multi-channel DAC is installed. As I understand it:

1. Acourate is not able to use more than one ASIO driver at the same time, meaning that it can not send output through the NADAC and receive input from the mic preamp at the same time.

2. The clock on the ADC (i.e. mic input) needs to be synchronized with the clock on the DAC.

Not sure how to do this at the moment. Will hopefully be cleared up in the next few days. Maybe dallasjustice or Blizzard might like to say something about the design of the system or how I could do it better.

 

[NorthSky]

I very like your "scientific" approach with clean design Keith. There is no mistaken.

 

[TBone]

Nice setup & post.

Eventually I will switch to using files stored in the PC's SSD as the source, but given that I have more than 4000 CD's, of which only half have been ripped, this isn't going to happen any time soon. For now and the immediate future, I will still need an optical drive. My hobby is listening to music, not sitting in front of my computer for hours upon hours for weeks on end mindlessly feeding CD's for ripping!

Ripping CD collections is often considered but a simple, long-winded, mindless/mundane task w/many audiophiles. It certainly can be considered just that, or ...

In my case; the act of ripping/archiving music morphed into a much broader project (forever active).

Ripping/attaining a musical library (per my expectations) often required extensive research, much frustration, and plenty legwork(*). Easily the most revealing, educational audiophile based project I've ever embarked, one which will pay musical dividends irrespective of present/future downstream equipment setup/choices.

(*) became such a large undertaking, I built a proprietary relational database in order to properly track/log specifics.

If audiophiles really want to understand what's coming out their speakers ...

 

[amirm]

I made CD ripping a background task while doing other things. It seems daunting but eventually it gets done.

 

[NorthSky]

Is this legal?

 

[TBone]

I made CD ripping a background task while doing other things. It seems daunting but eventually it gets done.

soooooooooo muuuuch easier than ripping vinyl; but that said, cd ripping was not quite as easy as I first figured ...

Near my entire CD collection needed to be delicately cleaned, after I realized the extent EAC read-errors. Read errors caused by progressing rot (mostly orig.pressings unfortunately) was yet another issue; dealing with HDCD rips w/peak extend/filters and older CDs with pre-emphasis ...

These problems can be eventually remedied to some degree or another (even rotting CDs), but what couldn't be remedied, initially, was the ~questionable~ mastering quality of the many pressings which littered my entire music collection. That issue, alone, became the most educational aspect of "ripping". I logged and questioned every rip; is that the best(per my expectations) transfer possible, do I own other transfers within other formats, are other pressings (in various formats) worth seeking out and attaining ... ?

Hence, the ongoing search & subsequent CD ripping towards my Music_Library continues ...

 

[amirm]

Is this legal?

Ripping CDs? Sure. Sharing the copy, no.

 

[TBone]

Keith, what is your subjective impression of the MPS-5? The only gear I'm familiar with are the Cary's, to some extent; did hear the Playback Design and that peaked my interest ...

 

[NorthSky]

Some CDs you cannot rip; they have a copy protection embedded in them. But it's ok because all the ones that have that feature they mostly suck anyway.
They are produced by the worst music recording companies.

As for rotten CDs, HDCD encoded CDs, pre-emphasis CDs, ... that you transfer on better material than the ones you bought from defective music record companies; we wouldn't have to do ourselves what them companies were supposed to do in the first place...manufacturing a decent product for their music lovers/customers.
It's a big shame the careless attitude of the music industry...in vast general.
________

Anyway, I'll follow the sun...Keith's direction.

 

[TBone]

Ripping CDs? Sure. Sharing the copy, no.

speaking of which; recently glancing at my pro sony w66 cd recorder manual, and it provides the option called "Setting Copy Bits" ... to engage, or defeat, the serial copy management system (scms).

Also, other than "pro" units (to my knowledge) all consumer grade cd recorders required proprietary CDRs called "Music CDR" for any intended copying, they were (and are) harder to find and cost ~3x more compared to common data disks. Even tape included a "copy" tax here; on record-able blank cassettes, based on the impending copying issues.

The first time I heard the term "ripping" was based on copying vinyl to digital; that meaning has since morphed ...

 

[TBone]

Some CDs you cannot rip; they have a copy protection embedded in them.

Have yet to find a CD I couldn't rip.

As for rotten CDs, HDCD encoded CDs, pre-emphasis CDs, ...

My rotting CDs and my EAC don't get along well, yet my Linn error correction system sails thru, so these can still be "ripped" from analog output, if required. HDCD requires intervention, a plug-in, esp those w/peak-extention enabled, hdcd filters are another issue altogether. Pre-Emphasis was an early CD issue which requires a decoder, all CD players include such, but not so other digital / recording options.

 

[NorthSky]

Not all CD recording machines were created equal. Most rip bit for bit, most don't have a copy protection disabler (for them copy protected discs from hell), ...all that jazz.

Now back to system synergy (interconnection) with Keith's state-of-the-art sound system designs.
{For ripping LPs and CDs using apps, recording machines, PCs, music servers, ...upsampling, etc., see the Ripping forum section under Analog/Digital Audio.}

It's hot here today; 34° Celsius (North Canadian degrees). * Only USA is still using the old metric system for degrees, distances, weights and currency.
No wonder that their measurements don't coincide with the rest of the world.

 

[Chuck Gerlach]

I'm with T-Bone. I have ripped about 1200 CD's and never had one I could not rip. I use dbPoweramp

 

[amirm]

I bought a bunch of used CDs last year and a couple caused serious issues with dbPoweramp getting stuck forever and not able to rip them. I overrode the error checking/detection and ripped them that way.

 

[NorthSky]

Some CDs have that logo on the back of their jewel case and on the front CD label:

Microsoft's and other program software for CD ripping (some), they won't allow you to record.
Sure you can get around it by using something else; it's only one more tool some CD manufacturers use from record labels like Virgin, Warner, Universal and others to impede on our freedom rights by making life hard to back up a copy from inferior music recording products.
But them record labels none of us here, audiophiles, buy inferior music recordings from them.

I only encountered very few like that. Now I don't buy ever from those music recording labels.
I don't encourage people who restrict my right to my own life's use.
No wonder that vinyl is on the rise; no copy protection with those discs.

Keith, that's what's missing in your systems; an analog rig with tapes and LPs.