Simple device for downsampling?


Is there a device such as a DDC or something else that can be placed in the digital path prior to the DAC and set up to downsample all higher resolution digital music files from Tidal, Qobuz, and local storage (all played through Roon) to a maximum 16-bit and 44.1 or 48 kHz, to facilitate a DAC with those playback limitations? 

Many Tidal/Qobuz files are already 16-bit, 44.1 kHz but almost as many are higher resolution files and I am unaware of any options within Roon to limit file resolution sent to the DAC.  Back when I used a Mac mini and one of the player programs, I believe we were able to select the output sample rate but now that I solely stream stuff thorough Roon, I am not sure how I would do that.  Thanks for any helpful suggestions.

mitch2

In Qobuz you can go into settings and select various maximum resolution levels.  Not sure how that’d work with their hi res music but it’s worth a try if you haven’t already.  Best of luck.

You can set the maximum resolution for your DAC in Roon. If you limit that it should downsample automatically.  Under Settings, select your device and scroll down, then select Advanced Settings.

The lowest you can go is 48 kHz.

Thanks guys,

Eric, I found the setting and set it to 16-bit, 48kHz.  A setting within Roon is exactly what I was hoping to find.  I will have a chance to listen in a little while and will report back.

The DAC I am trying to accommodate is pretty cool or I wouldn’t have even tried the down sampling.  I am having sort of a mini DAC play off here between two I have owned for a year or two, this sample-limited DAC, and the Mola Mola which will get here on Monday. Thanks for the help!

Thanks again everyone.  The fix within roon settings is a nice solution since the setting is specific to a specific endpoint/zone so, by dedicating this DAC to a specific endpoint, I could then use other DACs with other endpoints/streamers set to full resolution without needing to go into roon and change settings.  One surprise is that the DAC has also been working well at up to 24-bit word depth so I have the settings at maximums of 48 kHz sample rate and 24 bits per sample and it seems to be doing just fine on the downsampled higher resolution material.

@lanx0003 - The DAC is a DAC-2 GT-24 by SMc Audio, and began life as a McCormack Audio DAC-1

There was a review of an SMc modified DAC-1 (UltraDac) posted to 6moons some years ago and I was curious as to whether it could really sound as good as the writer described.  Since Steve and Patrick have done a wonderful job of building my amps and my preamplifier/buffer, I purchased a dirt-cheap DAC-1 a couple of years ago, sent it to SMc Audio, and told them "no rush guys."  Patrick called a couple of months ago and asked, "are you still interested in a DAC," so I told him "sure."  As you can see in the photo below, what they have come up with is quite a different beast from the DAC discussed and pictured in that original 6moons review.  It has a new board, better transformers, their Gravity Base, and an upgraded DAC chip that will do a sample rate up to 48 kHz (the original chip only did 44.1 kHz). They have customers using this DAC all over the world with the only consideration being the resolution limitation.  I imagine many clients like this as a dedicated DAC for (redbook) CD players. Patrick told me, "give the transformers quite a bit of break-in time" but even within the first day it sounds very good and particularly does a nice job of displaying a rich musical tone, spatial information/soundstaging, and just the right balance in the areas of dynamics and resolution, where there is plenty of both to provide a sense of realism without going over the top toward an in-your-face type presentation.  Overall, so far, it does nothing "wrong," is very musical, and seems to be the type of equipment that is enjoyable over the long haul.  

As background, I have owned a number of DACs and had a couple of others in my system for extended auditions such as Ayre QB-9 DSD and Aqua LaScala.  I have owned much of the Metrum line-up including the top level Adagio and Pavane (I liked Pavane best), and the Jade, which I own and use for my outdoor system.  I have also owned several DACs in the Mojo Audio line-up from the Mystique v3 through the Mystique evo Pro (which I still own), as well as the latest Mystique X SE (which I used for the past year and didn't like quite as much as the Pro).  I couldn't pass up a good deal on a Mola Mola Tambaqui, which is scheduled to arrive here on Monday. 

My comparisons will be between the SMc DAC-2, Mojo Mystique evo Pro, and the Mola Mola.  My set-up is fiber from my router to a Mojo DejaVu server/streamer then a pair of Bonn Silent Angel N8 switches, then the Network Acoustics muon LAN cable and filter into a Metrum Ambre Roon endpoint and coaxial cable into the DAC.  I will also try USB from the streamer into the Mola Mola.

@mitch2 It seems that DAC-2 has a better power supply than DAC-1, which originally featured a Crystal Semiconductor CS8412 chip (handling 48kHz), as per Mr. McCormack. I'm curious about the chip used in DAC-2. It may still be the same chip since you mentioned it is limited to the same sampling rate. I've come across comments from several users about upgrading to CS8414, which can handle 96kHz with improved audio performance.  Mr. McCormack must have a good reason for sticking with the old chip if that is the case.

(McCormack DAC-1 Deluxe Ed.)

Yeah, I haven’t opened it yet but Patrick told me the original chip only operated to 44.1 kHz so the CS8412 must be the second chip they used as he told me 48 kHz is the limit, which my use so far confirms.  At least it seems to accommodate a 24-bit depth.  He also told me whatever chip they are using is smaller so needs a mounting chip that matches the original pin size.  I will see more when I get around to opening it up and taking a closer look.

I believe the DAC chip is the smaller chip sitting on the red base in the picture of my DAC.  Does that conform with where the DAC chip is located in your DAC-1?

You are right, and that chip seems to bear a great similarity to https://www.ebay.com/itm/1X-CS8412-CS-Digital-Audio-Interface-Receiver-SOIC-to-DIP-adapters-CS8412-/120777575789?pt=LH_DefaultDomain_0&hash=item1c1ee78d6d

I don't own the DAC-1 in the attached picture so I could not confirm but, if you count # pins on SOIC (or SOP) and DIP (zoom in), they are both 28 pins (SOIC28 to DIP28) which is the same as in DAC-2.

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@mitch2 

From the picture posted with the lid off I’m surprised that they didn’t change that to be a dual mono design. I see two transformers which is what reminds me of that architecture. 
I’m having a hard time trying to envision what this Dac would sound like as I haven’t heard a dac with a CS chip since the Audio Research Dac 3 MKII (I think). And that dac had the coloration of tubes as well. Still, your SMC is going to be totally old school compared to the Mola Mola (assuming that your limiting the sample rate sent to it as well) as it will upsample everything back to 32 bit and apply some heavy filter processing afterwards. 
Is your goal just to compare the two for kicks or to ultimately decide which one to keep? I don’t know anything about your system or musical tastes but I know which dac I’d be betting on! I’ll be interested in hearing about the results of your test.

"Is your goal just to compare the two for kicks or to ultimately decide which one to keep?"

I have four and will keep two or three.  The comparison is for kicks, and the first decision is which of them to keep in my main system.  I have a Metrum Jade in my outdoor system and could easily use either the SMc DAC-2 or the Mojo Audio evo Pro for that system since the Jade should be easy to sell.  I will not down sample the signal going to the Mola Mola (or the Mojo evo Pro) during comparisons.  The idea is not to have a level playing field for comparison but rather to hear what each of the DACs do best and then decide which sounds the most musical and enjoyable to me.  I will also try all the input options for each.

The Mola Mola Tambaqui is here and warmed up so the DAC comparison has started.

The comparison is through Roon and it seems both the Mola Mola and the Mojo Audio Mystique evo Pro sound best when connected directly to my Mojo Audio DejaVu server using a Network Acoustics muon USB cable. The SMc DAC-2 is connected through a networked Metrum Acoustics Ambre Roon endpoint via an Oyaide silver coaxial cable. The signal sent to the SMc DAC-2 is being down sampled to 48kHz and 24-bits, while the signal to the Mola Mola and Mojo DACs is the full resolution of the music file.

Early impressions include just how good the SMc DAC-2 sounds and how it mostly holds its own against the other two (over $10K) DACs. The Mola Mola sounds better to me through its 6V output than using the reduced 2V output, and it seems to do nothing wrong. It is very musical, smooth, dynamic, and engaging at all volume levels. I certainly understand the rave reviews of the Mola Mola DAC. OTOH, the Mojo evo Pro may display even more tonal color and body so the comparison is certainly not a slam dunk. The SMc DAC-2 has a pair of large Jensen output transformers that reportedly require at least a couple of weeks of break-in. I am a long way from conclusions.

@mitch2 

Interesting to hear your thoughts so far. As your running the Mola with the 6V output setting are you able to run the Mojo and SMC with balanced or AES outputs or are you just having to level match?

Not sure what the output voltage is on the Mojo and SMc DACs so I am matching output volume by ear.  The 6V output from the Mola Mola DAC seems to add dynamic punch and life to the music, regardless of the output volume.  I found the 2V output to sound comparatively bland.

I would recommend installing a sound level meter app on your phone (at least) and use that with a very consistent tone for setting levels. I do this when comparing dacs and set the levels on different channels on my preamp.

A higher output almost always sounds better in comparison to a lower one and can definitely trip up a comparison.

According to Mojo’s website the Mystique will output 2.5V single ended and 5V balanced. I don’t believe you mentioned anything about SE vs Balanced. I wasn’t able to find anything regarding the SMC unit.

 

I didn't mention that my system is balanced throughout so all three DACs are using the balanced outputs.

At 6V vs. 5V, the Mola Mola and Mojo DACs are pretty close in level but at (I believe) 2V, the SMc DAC is at a noticeably lower output voltage than the other two so I do increase the volume when comparing with that DAC.   Good suggestion on the phone app although the differences I am hearing are not solely related to impact/output level as I seem to notice differences in body and dimensionality between them.  Tonally, the differences are not as apparent and all three DACs are similarly resolving, with maybe the Mola Mola a slight bit better than the other two in that area.  However, I don't believe resolution will be my deciding factor. It is still early.

I am excited to see your findings especially with the SMc DAC2.  I had Patrick update a DNA.5 a few months ago and he mentioned a new DAC2 he  built and that it may not be able to process the bit rate as the new DAC's but  it was the best DAC he had listened to.  He said it just sounded good and musical.

 

@brbrock - Patrick and Steve do incredible work.  I have a pair of their big monos and an upgraded preamp/buffer in my system.  Their stuff is just so musical.  I looked back at some notes and realized I first asked them about their upgraded DAC in 2013, ten years ago!  I contacted them after reading the sixmoons article/review by Francis Baumli, Ph.D. who raved about his upgraded SMc Audio UltraDac

The DAC comparison is in full swing.  The newer units, including the SMc DAC-2, have been getting almost around the clock repeats of Ayre's full frequency sweep to help with any break-in that might be needed.  Patrick said the large Jensen output transformers may require a couple of weeks before they reach close to full potential.  

What I can say for now is that Patrick's comment, "it just sounded good and musical" is spot on.  As I said earlier in this thread, "The idea is...to hear what each of the DACs do best and then decide which sounds the most musical and enjoyable to me."  I plan to keep the one or two of them that I enjoy listening to the most.  Based on what I have heard this weekend, I suspect the SMc DAC-2 may be one of the two.

Mitch are you still using your other SMc equipment?  If you are can you tell me about it?  When you had it built and what they did"?

@brbrock - I started conversing with Steve McCormack about the SMc Audio upgrade possibilities probably 10 years before I actually had them do work for me.

In 2012, SMc upgraded a McCormack TLC-1 passive/buffered preamp for me using design features based on their highly regarded VRE-1 preamp, including the exact outboard choke power supply, the Shallco discrete resistor (AN resistors) volume control, Lundahl transformers wound with Cardas wire, and special capacitors, connectors, and wire. I have run through about 20 well-respected audiophile preamplifiers in my system (a couple over $10K) and none of them sounded as good to me as that SMc TLC-1 Signature Edition. Several years ago, I decided I needed to have a remote control for volume and a digital display that I could see across the room. Steve still wasn’t putting them in upgraded TLC-1s (he may be now) so he helped me modify my preamp by taking the volume control out of the circuit and replacing it with two large Audio Note silver resistors so that the unit is now a unity-gain buffer without a VC. I run my DAC output into a custom made Khozmo passive unit (dual mono, single input/output, large display, remote), and then from the passive through the SMc TLC-1 SE buffer, then into my SMc Audio amps.

The amps started as two McCormack DNA-1 stereo amplifiers and then Steve and Patrick did everything they could (at the time) to improve them including using their new circuit boards, basically all new parts, and their gravity base. Pictures of the amps are on their home page (the black amps at the bottom of the first block of pictures). They sound outstanding to me and also do an excellent job of powering my hard-to-drive Aerial LR5 speakers.

I have been speaking with Steve and Patrick for a couple of years about their DAC and sent them an old,stock DAC-1 that I found on-line (had it shipped directly to them). I sort of forgot about the project and then a couple of months ago Patrick called and asked if I still wanted to do the DAC project. The result is better than I imagined. If you look at the picture earlier in this thread you will see they have a new board that they now use and have done a remarkable job on the power supply and upgrading parts. They also used their Gravity Base on the DAC-2. By all accounts I can find, the DAC chip is basically bog-standard, the DAC only accepts a S/PDIF input (coax), and the input must be limited (i.e., down sampled if necessary) to 48 kHz and 24-bits, but this thing sounds way better than I ever imagined it would sound. I have three DACs here now and what I can say is that, after just over two weeks, the SMc DAC-2 holds its own with the others, and maybe more. The other two both cost in excess of $10k.  It is a very musical sounding DAC, a little different from the R2R DACs I have been using, but just as musical and very enjoyable to listen to.

Hi @mitch2 , anything new to report on your comparison? 

I own a Mojo EVO B4B dac (love it), but have been getting the itch to try something else.  Your review so far has me thinking the SMC-DAC2 could be right up my alley.

Does SMC plan to put the DAC2 into production?  I don't see it listed on their website.

@veroguy 

I have not heard anything about SMc having plans to put the DAC-2 into production.  You could contact Patrick at SMc directly for more information.

The SMc DAC-2 does sound very good to me, but so does the B4B (one of which I previously owned).  I have been conversing with Benjamin about why I like the sound of my EVO Pro so much and when I opened mine up, I found that it contains special AD1862 Z DAC chips, which are apparently much more precious than the standard version.  There is apparently one more recent upgrade that I could do to the EVO Pro, or I could move my Z chips to an X SE and have the upgrade performed on that DAC.

In any event, unless you are willing to chase down rabbit holes, you may want to remember why you liked the sound of the B4B in the first place, and stick with that.  The Mola Mola is a different animal and sounds like perfection, but that version of perfection may not be the sound I like best.

Thanks, Mitch.

I didn't know there was a "Z" version of AD1862.  Perhaps I should call Ben and see if that's an upgrade option, as well as doing a few of the Pro upgrades to my B4B - like the amorphous core chokes.

I've heard the Mola Mola head-to-head with my Mojo.  It was indeed close to perfection, but I still preferred the Mojo Mystique - a touch more natural, IMO.

I'd like to hear the T&A DAC 200 - totally different beast, but the reviews have been pretty outstanding.

@veroguy - You should call Benjamin to discuss possibilities.  He may have some new stuff on his horizon - as usual.

Mitch2 I am following up on your findings.  I am very curious of the outcome.

@brbrock - I will let you know which I like better when I decide to put one of them back in its box.  I did sell the Tambaqui but still have the Mystique EVO Pro and the SMc DAC-2 set up in my main system.  They each have strengths and regardless of whichever one I am listening to, I never feel short-changed. 

The comparison is not exactly straight-forward as the DAC-2 only accepts a S/PDIF input while the EVO Pro arguably sounds best through its USB input, which I am currently feeding through a Sonore Signature Rendu SE Optical streamer, while the S/PDIF connection to the DAC-2 is coming through a Metrum Ambre streamer.  I also occasionally compare them on a more equal basis using the S/PDIF input on the EVO Pro, although similar characteristics and differences are still observed.

Tone is very nice on both as are dynamics.  The EVO Pro has a bit more of that organic/smooth/musical presentation that R2R DACs are known for and it has the special "Z" version of the two AD1862R DAC chips, which the designer believes improves on the standard version and previously offered for an additional $1K each, when he could get them.  The presentation and soundstaging on both is realistic and not overblown, although the EVO Pro may portray a touch more dimensionality.

Another consideration is that the price of the EVO Pro is over 2x the price of the DAC-2.  As a benchmark, I would definitely take the DAC-2 over the (slightly lower priced) Metrum Jade that I have in my outdoor system.  If I had to choose only one of them today, I would probably pick the EVO Pro but that choice may be more related to subjective musical preference than objective performance, and could also indicate my preference for R2R DACs.