Showing posts with label Roksan. Show all posts
Showing posts with label Roksan. Show all posts

Friday, 7 November 2014

MEASUREMENTS: Roksan TMS (1) Wow & Flutter - PlatterSpeed test.

Greetings from this place:
Port city of Xiamen, China - just across from Taiwan.

Wrote this up right before I left Canada to go to Asia...

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Hello folks, while you're working on the vinyl LP test and as I prepare to go overseas for a few weeks, I thought it might be interesting to post the objective PlatterSpeed results from the Roksan turntable as well as a couple more pictures of the setup...

It is a thing of beauty:


Although there have been updates to the TMS design (I think TMS 3 is the latest, here's a TSM 2 review from 2003), the appearance and general design principles seem to have stayed constant over the years. The build of this device is top notch and smoothness of operation appears excellent. Switching from 33.3rpm to 45rpm is easy with the push of a button up front.

Using the same Adjust+ Test LP to measure as I did previously with the SL-1200, here are the 33.3 rpm charts and calculations as per PlatterSpeed measured off the same iPad:



As you can see, it measures quite well. It's running a little fast with a mean frequency of 3156.5 Hz instead of 3150 over 60 seconds or so. Wow measurements with the DIN IEC 386 plugin is a little higher than the SL-1200, a similar pattern with the raw frequency maximum deviation. But when lowpassed, the maximum deviation was the same as the Technics at +/-0.02%.

Here it is measured at 45 rpm:



Again, it's a bit fast at 45rpm as well. Remember the target "mean frequency" at 45rpm should be 4252.5Hz. There's only a slight increase in the DIN IEC 386 wow measurement and slight increase in the lowpass-filtered result compared to 33rpm demonstrating good stability with the increased table speed.

It'll be fun to see the LP blind test results! Keep the entries coming - you have to end of November :-).

Enjoy the tunes.

Friday, 17 October 2014

TEST: Archimago's LP Needle Drop Blind Test.

Hello everyone. Welcome to another "blind" test! Unlike the previous High Bitrate MP3 Test last year and the more recent 24-Bit vs. 16-Bit Test, this one is much more subjective and essentially for fun :-). Not that previous tests weren't fun, but the results of this one is more for the experience of having tried (that's at least part of the fun of this hobby I hope!)...

This time, we're looking at vinyl "needle drops"; digitized output from turntable setups. You can download the test file here:
ftp://lptest.dyndns.org 
Login: LP 
Test: test
Download the file "Archimago's LP Test.zip" (~125MB).

Alternate download site (thanks again Ingemar):
www.privatebits.net/archimago/Archimago's LP Test.zip

Within the ZIP file, you will find 3 sample FLAC files - A, B, and C. Each is a high-resolution 24/96 audio recording of 2 minutes, 2 seconds duration. I trust this is a long enough sample to evaluate the sound quality.

Each file was created with the same LP; a 2012 180gm remaster of Paul Simon's "Graceland", specifically the last track on side 1 - "Diamonds On The Soles Of Her Shoes" (Matrix / Runout (Side A): 88691914721-A RE1 20315.1(3) STERLING RKS) so there's maximal inner groove distortion potentially. This LP is completely "virgin", purchased new about a month before I did these recordings and never been played before these samples. The LP looked clean and about as perfect (eg. no warps, dents, fill defects, scuffs, scratches...) as can be. I used an air blower to remove any obvious surface dust. It was NOT washed prior to playback since I did not want to inadvertently add anything (nor can I say I removed any potential deep embedded dust from the factory).

The recordings were done in the following order with the following systems:

1. Roksan TMS (first generation), SME309 magnesium tonearm, Ortofon Cadenza Black cartridge fed into a Whest PhonoStage.20 preamp. Audio output was through a pair of shielded 6' RCA cables plugged into the preamp (no balanced XLR on the Whest). Total cost for this setup should easily exceed $5000 on the used market.

Took a shot right after the vinyl needle drop was done...

2. My own stock Technics SL-1200 M3D turntable. Denon DL-110 cartridge fed into the Emotiva XSP-1 preamp (Gen1). This cartridge is a high-output moving coil (HOMC, 1.6mV) so the preamp was set at standard MM load and 47kohm load. Output recorded off 6' of MonoPrice balanced XLR cables. Total cost of this would be <$2000 considering the Technics was bought used. The Denon DL-110 costs about $150-$200 new shipped.

3. My own stock Technics SL-1200 M3D turntable. Shure M97xE cartridge fed into the same Emotive XSP-1 preamp (Gen1). This is a standard moving magnet cartridge with 4mV output. Again, 47kohm setting used on the preamp. Output recorded off 6' MonoPrice XLR cable. Slightly less expensive than (2) above with the Shure cartridge <$100. Again, total cost of this system would be <$2000.



Technics setup calibrated using Baerwald geometry and SME tonearm using the SME-supplied protractor (Stevenson?). Vertical Tracking Force optimized with digital scale (Ortofon = 2.3g, Denon = 1.8g, Shure = 1.25g dynamic stabilizer disengaged). Azimuth set to perpendicular by visualization using a mirror protractor. I tried to optimize the "stylus rake angle" to something like 92-degrees (I honestly believe it makes no sense to spend too much time or effort on this unless extremely misaligned; vinyl thickness differences and mild but common surface unevenness will easily affect this):

eg. Denon DL-110 stylus on vinyl. Photo taken with Nikon D800 using Tamron SP 90mm/2.8 macro lens at f8, manual focus on small tripod. Angles estimated & measured on screen with MB-Ruler.
Analogue-to-Digital conversion was done with the Creative E-MU 0404USB device at 24/96 using Audacity to record. I can confirm with A/B switching while playing the digital file off a Squeezebox Transporter and the Technics turntable playing at the same time that the sound is essentially identical when volume matched.

For consistency, the digital files were:
1. Trimmed to ~2'02" in length.
2. First second essentially silenced to provide the same "lead in".
3. Last 2 seconds faded out to silence.
4. All file volumes RMS normalized to -18.87dB. Note that there are a few clipped samples due to unanticipated dynamics of this recording but should not impede evaluation.
5. All samples compressed to FLAC lossless and tagged.
6. Randomized to Sample A / B / C.

Other than the above there was no other processing done to the files. Nothing like noise reduction or ClickRepair for example.

As you can see from the DR meter log file (foo_dr.txt from foobar2000 plug-in) in this ZIP file, the music has a good dynamic range of 14dB. (Excellent LP remaster!)

Your task:

1. Listen to the 3 tracks in native 24/96. Which sample did you think was the best? Which did you think was the worst? (It's OK to also feel there's no preference or even if you notice a difference, think that it would make no difference to musical enjoyment.)

2. How much difference did you hear? Although the cost differential is much more between the Roksan vs. Technics setups, suppose your system sounded like the "worst" sample, would you spend $1000 to upgrade it to sound like the "best" sample?

3. Go and fill out my simple survey. All 7 questions are mandatory and I will have to delete responses that have not been filled out correctly. Should take <5 minutes. Please also let me know which computer/DAC and what headphones/speakers used. Also whether you used something like the Foobar ABX tool for evaluation.
(http://freeonlinesurveys.com/s.asp?sid=9qk9tpzbxq8uwlk539831)

As usual, thanks to all who try this out! It's not often that one gets to hear turntable setups side-by-side and this was about as "controlled" as I could find a way to do this to get a taste of what disparate gear could sound like. As usual, although this test is more subjective than previous tests, make sure to listen and not just look at waveforms in an audio editor, also, I think it's better not to discuss one's results until after the test is complete so as not to influence others.

I'm going to run the survey until November 30th - I'll be overseas for a bit so in case there are issues, please leave a note in the comments section if you run into any difficulties. Have fun with this!

Best regards,
Archimago

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Disclaimer: I believe this test conforms to the spirit of "fair use" for copyrighted material for the purpose of education and research. The author derives no financial benefit from conducting this survey.