Maybe I shouldn't say "testing". It more like a simple listening comparison...
A while back I posted about a video jukebox project that plays music from my media server through a PC connected to my TV and soundbar, and displays trippy visuals synced to the music in 4k resolution at 60 fps. I recently put together a better audio system in the living room and wanted to connect the jukebox to it (and to eventually get rid of the soundbar). The jukebox PC has line outputs that I could connect to the stereo system, but the quality of the audio from the PC is not great, so I bought a USB DAC to connect between the PC and the stereo.
The test set-up. The little black box on top center is the SU-1 DAC. The white thing is a wireless router.
The new DAC is an SMSL SU-1, very popular among Youtube reviewers and on audio forums, and cheap, too- $80 via amazon.com. There's a good technical review here. It has USB, TOSLINK optical, and coaxial digital inputs. There is a single button on the front panel to select the input. I plugged the USB cable into the jukebox and analog outputs to the Krell and it started working without any messing around (it's powered by the USB port). It definitely sounded a LOT better than using the computer audio out to connect to the Krell, so I count that as a successful project completion.
This is the SMSL SU-1 DAC guts.
Then I wondered if the new DAC (and its analog output) would sound any different/better than the DACs (and analog outputs) in the CD player and the Squeezebox.
The TEAC VDRS-20 CD player cost about $2500 new in the early 90s (that's equivalent to $5600 of today's dollars). It might seem ridiculous to compare its DAC/analog output to that of a new, $80 DAC. However, with improvements in technology, I think it's entirely possible that a $80 DAC might get the best of a 30 year old $2500 CD player.
The Squeezebox Touch cost $300 when it was new, in 2010 (that's $433 in today's dollars). It seems more reasonable to compare the new DAC to it, simply based on the similarity of the prices. However, technology has changed a lot- the iPhone was released in 2007 and look how far things have come. Maybe the new DAC will blow the Squeezebox out of the water. Let's see.
Note: I'm not an audio reviewer, and my vocabulary does not include the purple superlatives that audio reviewers often use. I'll tell you if I hear a difference and what I think of it. But that's about it.
Another note: The CD player, DAC, and amplifier are stacked so cables between them are short and identical. I expect no audible differences based on the cables.
First test: CD player balanced analog output vs unbalanced analog output
Balanced I/Os were originally used in stage and recording studio equipment to allow long cable runs without signal degradation. AFAIK they started showing up in hi-fi system components in the 90s, and seem to be becoming more common, even in less expensive gear, at least when the equipment's form factor allows the larger XLR connectors, and the budget allows for their cost.
I played several CDs and switched between the the balanced and unbalanced outputs. The only difference I noticed was that the balanced output seemed to be at a slightly higher level than the unbalanced outputs. Otherwise I could not hear any difference between them. For the remaining tests, I used the unbalanced analog output from the CD player because the SU-1 DAC only has unbalanced analog outputs.
Second Test: CD player unbalanced analog out vs DAC coax in and unbalanced analog out
The VRDS-20 allows both analog output and digital outputs to be active at the same time, so I connected the unbalanced analog output to the Krell amp and the unbalanced analog output from the SU-1 DAC to another input on the Krell amp. The CD player coax output connected to the SU-1 coax input.
During playback I could instantly switch the inputs on the Krell to compare the sound from the CD player's internal DAC (a Philips TDA1547 bitstream type) and analog stage to the SU-1 (an AKM4493S DAC chip) DAC and analog stage. I could not hear a level difference - they were very closely matched.
After swapping multiple CDs, switching back and forth between the CD player and the DAC, and careful listening, I could not hear any difference between the two.
Third Test: CD player unbalanced analog out vs DAC optical input and unbalanced analog out
I connected a toslink cable between the CD player and SU-1 DAC, switched the DAC input to optical and tried again. Same result. I was unable to hear any difference between the CD player's unbalanced output and the SU-1 DAC.
Conclusion?
The fact that I couldn't hear any difference between the CD player's analog output and the SU-1 DAC doesn't mean there aren't any differences, only that any differences were too small for me to hear them. My speakers are not especially great, and maybe the room is not set up in an ideal manner for them. The CD player is 30 years old and hasn't been serviced (recapped), so it could be operating at less than ideal performance. Finally, I'm 66 years old and my ears aren't what they used to be (too many ZZ Top concerts and too many hours around high volume dental suction), especially at high frequencies.
OK, this time with headphones
My speakers aren't so great, so I repeated the both the coaxial and optical input tests using my Koss ESP/950 electrostatic headphones with their companion E90 amplifier plugged into the tape loop on the Krell amp. These headphones are considerably better at sound reproduction that my (or just about any other) speakers, but they won't reveal anything about the soundstage you might hear with properly set-up speakers.
Result
Unchanged. I was not able to hear any differences between the the CD player's DAC and the SU-1 DAC. Maybe the SU-1 is that good. Maybe my ears are that bad. All I know for sure is that there's no point for me to spend any more on a DAC, except to get more or specific I/Os that might be useful in my system.
Squeezebox Touch vs SMSL SU-1
I repeated the coax and optical tests with the SB's unbalanced analog output connected to one input of the amp and the SU-1 DAC. I tried with speakers and with headphones. The squeezebox doesn't allow analog and digital output at the same time, so I couldn't switch back and forth as readily as I could with the CD player. I did the best I could. Result: same. I was unable to hear any differences between the analog output of the SB and the analog output of the SU-1 DAC.
Comparing the measurements in the three reviews it is clear that the technology has indeed improved and the SU-1 DAC is much better than the DACs in both the VRDS-20 and the Squeezebox, and the Squeezebox is a bit better than the CD player.
Some people commented that the SU-1 produces popping noises audible during silent passages and between tracks when used as a USB DAC on a Windows 11 PC. I have not had any problems like that in several hours of listening through my Windows 10 PC. In my long experience, problems of any sort on Windows PCs are frequently OS or configuration problems. Maybe my windows configuration is somehow different from others. Maybe SMSL changed the firmware in the DACs coming out of the factory. We'll probably never know. If I start to have any problems with the SU-1 I'll update this post.
For me, the only reason to spend more on a DAC would be to get functions and I/O that the SU-1 doesn't have.
I have set up a proper stereo system in my living room that sounds much better than the sound bar, so naturally I wanted to connect the jukebox PC (runs windows 10) to the stereo system. I tried the analog audio out from the PC but the sound quality wasn't great. I decided to try adding a USB DAC to the system, and did some online research and found a lot of people seemed to like the SMSL SU-1 DAC that sells for $80 on amazon.com. I ordered one and tried it out. It just plugs into the PC with a USB C cable (that also powers the DAC). It was immediately recognized as a "USB headphone" and audio switched from the sound bar to the DAC.
I buy a moderate amount of stuff from China and my experience is that it almost never meets advertised specs, and drawings on web sites are almost always different from the parts you receive. I found a technical review of the SU-1 DAC at audiosciencereview.com that includes measurements of the DAC's performance. In this case the measured performance matches the promised performance on the SMSL web site. It's a VERY good DAC, especially considering the low price.
Audiosciencereview.com also just did a tech review of the VRDS-20 CD player which I happen to own and is connected to the living room stereo system. Their tests show that the SU-1 DAC is much better than the one built into the CD player. I tried comparing the two and found the measured differences are inaudible to me when the CD player is playing music.
Update 7/7/23
I have a server PC that runs Jellyfin to send video to the Nvidia Shield TV Pro connected to my TV and runs the Logitech Media Server to send music to my Squeezeboxes and to the sound bar connected to the TV. I recently realized I could just run Squeezeplay, a software player that plays music streamed from the Squeezebox server, on the Jukebox PC directly, so I don't really need another music player on the Jukebox PC running MilkDrop 3, and I don't need to store any music files on that PC. Control is still a little wonky- I can select music and playlists using my phone or any computer on my network, but I still have to manually start Squeezeplay and MilkDrop with a keyboard/touchpad connected to the Jukebox PC.
Now back to the original post:
I recently got a wonderful LG C2 77" 4k OLED TV to replace my 15 year old, 52" Sony TV, and it got me thinking about a project that I've had in mind for a few years. I've always liked music visualizers that generate trippy graphics in sync with music, such as the MilkDrop visualizer in WinAmp (remember WinAmp?). There are other visualizers, but none that I have seen (and I think I've seen them all!) that compare to MilkDrop. Someone has updated both WinAmp and the MilkDrop visualizer packaged with it in a program called Wacup that you can DL here.
I decided to try out Wacup on my 9 year old ThinkPad W530 laptop that I use as a desktop machine for CAD, etc. That computer has an Nvidia Quadro K1000M graphics card with 2 GB of dedicated RAM. First I tested it on the QHD (2k) display on my desk and results were pretty good. It was able to drive the monitor full screen at 2k resolution and 60 fps for many presets, though some bogged down or failed outright. Next I tested it on the TV at 4k resolution. I bought a mini DVI to HDMI cable via amazon.com and hooked it up. The result was pretty good, but many of the presets slowed down or failed and the screen went blank, something I attributed to the relatively low power of the graphics board in the laptop.
A little later I found that someone had rewritten MilkDrop as a stand alone program (MilkDrop 3) that will sync trippy visuals to any audio in the computer, and added a lot of new capability to it in the process. I'm not a huge fan of the WinAmp UI, and wanted to try the added features in MilkDrop 3 so I installed it and used VLC for further tests.
When MilkDrop 3 ran on my ThinkPad, the Windows task manager showed that only one processor of the i7 CPU in the laptop was operating at 20% while the GPU was getting slammed (>80%) by many of the presets. So I knew that I needed to focus on the GPU and started a survey of low cost graphics cards to see what kind of PC I could build for as low cost as possible to get 4k at 60 fps.
This posed a problem. How do you know what sort of graphic card specs you need to display the visualizations at 4k and 60 fps? I was posting questions about graphics card capabilities in an online forum and someone suggested that running MilkDrop at 4k resolution was pointless because nothing stays on the screen long enough to see that level of detail. Spoiler alert: now that it is working, I'd say that was wrong. There is a lot of very fine detail in many of the presets that looks great either close to the screen or from far away. I guessed that a card with maybe 10x the performance of the Quadro should do the job, so I started looking for card model numbers that would do that in order to get some idea of what a card would cost.
Along the way I found some interesting videos on youtube showing how to connect a gaming type graphics card to a small form factor PC, like this one:
The GTX 1650 card in the video was about $180 new, and its performance seems to be 10-12x that of the Quadro, so I thought it might be a good one to try. I started pricing everything out and quickly came up to about $450-500 to build a PC to do the job, but thought it would look pretty bad when it was done (like the one in the video above, though it will probably be hiding inside a cabinet under the TV). That seemed like a little too much to spend to end up with an unsightly mess.
I was about to shelve the idea and wait for technology to catch up (i.e. get cheaper) when I saw a deal on a refurb HP desktop PC from woot! that had an i7 6700 CPU, 16 GB of RAM, and most importantly, came with an Nvidia GTX1660 Super graphics card (6GB of DDR6 RAM) for $439.
After setting up Windows 10 Pro (already installed on the computer), installing MilkDrop 3, copying some music files to the HDD, and installing the latest gaming driver for the graphics card, I connected it to the TV and tested it with VLC playing the music.
I am happy to report it works very well! Visuals are detailed, super smooth at 4k resolution and 60 fps, and respond well to the beat of the music with hundreds of presets tested. There are no slow downs or blackouts, and of course, everything looks great on the big OLED display. Audio gets sent to the TV via HDMI from the computer, and from the TV to the sound bar via the eARC HDMI connection. The visuals sync with the music very well in this arrangement.
Running full screen at 4k resolution and 60 fps, CPU use is minimum- I've seen it go as high as 15%, so you might be able to use a much lower spec CPU, and the GPU rarely gets above 40% utilization. This report is generated by GeForce Experience, installed along with the gaming driver for the graphics card.
MilkDrop reports the name of the preset and frame rate when you hit the F3 and F4 keys. At 4k full screen I've never seen the frame rate drop below 58 fps on any preset.
One thing that concerned me about the GTX1660 S graphics card was the big fan on the GPU heatsink. I was afraid it might be pretty noisy. So far, it has been super quiet, even after hours of continuous operation.
During initial tests I ran into a few problems- every few minutes, for no apparent reason, the audio would drop out for a fraction of a second, and after about 10 minutes or so the TV would go black and the audio would switch to the computer's internal speaker.
Win 10 defaults to turning off the display after 10 minutes without mouse or keyboard input. That's an easy fix- go to settings>power and battery>display and set the screen to blank "never". That fixed the black screen and audio switching to the PC's internal speaker.
I switched to the Groove Music program that comes with Win 10, and found it worked without dropouts. There's probably some setting in VLC that can fix the dropout problem. I will probably try out a few other music players to find the one that has a UI that I like, and performs well without dropouts.
I shut off all the audible notifications in windows so none of those noises happen while I'm listening to music. I also bumped up the size of the text and mouse cursor on the screen so I could operate the computer from the couch.
Controlling it
I needed a convenient way to select music to play, construct playlists, and start and stop them from my couch without having to have a keyboard and mouse plugged into the computer. For now I'm using Groove Music player to play the music stored on and selected from a local HDD in the computer (it came with a 3TB drive), and using a miniature Bluetooth keyboard/trackpad that doesn't seem to work very reliably, so I'm going to look for something else to use.
Mini Bluetooth keyboard/trackpad that sort of works, but not very reliably.
I use a Logitech MX Keys Mini Bluetooth keyboard at my desk computer that is just about 100% reliable. I'll may just add a Bluetooth mouse and take it to the couch when I'm setting up the music and visuals, or since I need my laptop to control Arrakis, maybe I'll set up remote desktop with the music/visuals computer and use that for the ultimate remote control.
More Presets
MilkDrop 3 comes with 500 presets when you download it.
You can find instructions for creating your own presets here. At first look it doesn't seem easy- it may take some study and experimentation.
One thing I found is that a lot of the presets include some very bright, flashing lights and colors that can be a strain to look at for even a few seconds (and possibly cause epileptic seizures in susceptible people). I am going to start going through the thousands of presets and see if I can create a bundle of them that do not flash that way. Watch this post for a link to them as I get going on it.
I have also noticed that some of the presets don't seem to have any beat detection at all and just do their own thing. I'll try to separate those from all the others. MilkDrop will run without any audio input and still make some very nice patterns to watch.
Here's what some of the double-presets look like in MilkDrop 3:
