Hi Jim, i get a similar result with the tracking tests with my RTA. Nothing vertical of the three levels shows any trouble at all, the only test causing trouble is the highest level of horizontal, this has been the case all through the developments I have made. I have never put this on the scope, just done the conventional way by ear, I may try that as well. M
Mike,
I guess if an arm can trace the signal at 15 dB, it is an exceptional one. Since I haven't seen anyone publish such data, I can't get the correct evaluation of the performance of my arm. In fact, I saw you used Visual Analyser. It has a scope, too. If you have HiFi News test LP, it has only one 15 dB track. For CBS test LP, it has 6, 9, 12, and 15 dB tracks. But for CBS test LP, you are not supposed to use a phono with RIAA. But for this test, I am not sure if RIAA will make any difference.
Jim
I guess if an arm can trace the signal at 15 dB, it is an exceptional one. Since I haven't seen anyone publish such data, I can't get the correct evaluation of the performance of my arm. In fact, I saw you used Visual Analyser. It has a scope, too. If you have HiFi News test LP, it has only one 15 dB track. For CBS test LP, it has 6, 9, 12, and 15 dB tracks. But for CBS test LP, you are not supposed to use a phono with RIAA. But for this test, I am not sure if RIAA will make any difference.
Jim
Hello Jim, I think you are correct about published data, there isn't much around, but I am sure it is clear from what I have seen that your arm is very good, that's probably why it interests me to explore openly the questions about the compliance or otherwise of the bearing with people like you responding and discussing!! - by the way you can see I recently made some improvements to coupling and results.
I use an old Hi Fi sound test disc, (cost £4.95 in 1981!!) and now prompted to look I find the Lateral modulation is slightly different, at 8, 11 and 14dB, anyway, the result is the same, it's the highest, 14 track that causes some problems. The vertical are lower levels. And yes, as you say I use VA so can probably put the scope on it, I have always used it in the traditional way by listening only, the only reason is that I have used the disc since way before VA existed!
I shall have a go with the scope and see what i can learn as well...........
Mike,
I just tried VA with an RIAA phono and CBS test LP. The trace is somewhat smoother but almost identical to the test result without RIAA. So, it doesn't matter probably if you use an RIAA phono or a microphone preamp for these particular test tracks. This is a 300 Hz 15 dB signal with an RIAA phono. I think your HiFi Sound Test LP is cut with RIAA.
Jim
I just tried VA with an RIAA phono and CBS test LP. The trace is somewhat smoother but almost identical to the test result without RIAA. So, it doesn't matter probably if you use an RIAA phono or a microphone preamp for these particular test tracks. This is a 300 Hz 15 dB signal with an RIAA phono. I think your HiFi Sound Test LP is cut with RIAA.
Jim
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I am a bit lost in this area Jim, however i will take a look over the coming days, meanwhile if I discern correctly you have both channels input to VA and one (A, L) shows a quite close representation of the wave but the other is distorted, is that what i am seeing please, and as its the 15dB torture test that's not surprising but why the difference between the two?
My disc description is in the pic below, i am not sure what this would look like at all........
My disc description is in the pic below, i am not sure what this would look like at all........
Attachments
Mike,
The track you used looks like an intermodulation distortion signal, IMD. It has 4 kHz and 400 Hz. Usually, you may use IMD to test VTA. The Ultimate Analogue Test LP has an IMD signal, 4 kHz and 60 Hz. It can be used for testing VTA. I have another piece of software, Multi-Instrument. Here is a screenshot. You can see that I configured the software to test all parameters of tonearm adjustments. They are red-underlined in the image.
For tracking tests here, the signal is actually a simple 300 Hz signal in the waveform at various levels. The high level of the signal is, the more difficult to trace it. If you have a 300 Hz signal, you may try it as well. However, you need to make sure of the level of that particular signal. Otherwise, it may not mean too much.
Here is an actual test for VTA. You can see f1 is 60 Hz and f2 is 4 kHz. IMD=4.95% for the left channel A and 4.10 for the right channel B.
Jim
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Guys I wouldn't worry about the 15dB test track very few cartridges will track this. A Stanton 881s will track it but this is special cartridge.
Jim that 15dB plot looks to me like the stylus is riding up the groove wall as the carriage is flung back and forth. If the arm can track 9dB I'd call that good there is not much on an LP that exceeds this. My pivoting arm and EPC-205 will track the 12dB if I increase antiskate and VTF but I never run this much antiskate and VTF. The Stanton 881s will track 15dB @ 1g VTF with just an increase in antiskate.
Jim that 15dB plot looks to me like the stylus is riding up the groove wall as the carriage is flung back and forth. If the arm can track 9dB I'd call that good there is not much on an LP that exceeds this. My pivoting arm and EPC-205 will track the 12dB if I increase antiskate and VTF but I never run this much antiskate and VTF. The Stanton 881s will track 15dB @ 1g VTF with just an increase in antiskate.
I have kept saying that the thin film of air in the air-bearing has damping effects and this is why my air-bearing arms are so quiet. Here is a good reading for that topic. In the article, they summarized three factors.
1. The squeeze film effect.
2. Mitigation of whirl frequencies.
3. Shock damping.
https://www.newwayairbearings.com/n...F6Q&utm_content=254704667&utm_source=hs_email
1. The squeeze film effect.
2. Mitigation of whirl frequencies.
3. Shock damping.
https://www.newwayairbearings.com/n...F6Q&utm_content=254704667&utm_source=hs_email
Sorry I missed your message, I was in a bad period so I stopped all works back then and took a break.
Recently, I have acquired a small bench CNC so I should be able to make parts in house for this project. I am just about to deliver the first prototype of my latest phono preamplifier to a customer in Italy that I worked on for the last year and half, and then I will be resuming this project and revive this post.
My mailbox should not be full in case you want to send me a message.
Tritium Turntable with Fluid damped Air bearing Tonearm. Arm weighs 40 grams, Table weighs 150lb.
How do you like your arm? What airpump system do you use for it?
The turntable, did you use microseiki parts and built a base around it?
The turntable, did you use microseiki parts and built a base around it?