Is this with a different phono stage since the Puffin doesn't do 460 ohms load? If so, couldn't that also explain the change in distortion?
Correct it's a different phono stage, that in the Devialet Expert 400. And it was checked -- the same phono stage doesn't exhibit that behavior at 200 ohms. So, maybe it's due to phono stage differences, but I wouldn't call it likely, given the nature of the distortion and how it looks at other loadings. Occam's Razor to me suggests behavior of the cartridge as likely first suspect, but one never knows. Regardless, it's not a tradeoff I think is a worthy gamble given current data given the negligible impact increasing the loading had on taming the peak and the ease of applying EQ. If it showed really great peak reduction at 460 ohm, I'd be tempted to add some external resistors to the Puffin to see how it looked in comparison, but it's not a good enough reduction for me to get excited about digging into. Especially it's so easy to EQ with little impact in the musical fundamentals band. Others, of course, are free to do their own tests and share data, which might be interesting.
I have both Lundhal 1931 and Hashimoto HM-7s in house. I'm planning to do some squarewave oscilloscope testing with them to assess ringing and try to unroot why the bass sounds different between them.
Sorry, I misread this earlier. I thought it said 1000 ohms. 100 ohm loading moves the peak lower into the audio band, below 10kHz. 7981 Hz is what the models predict, and that matches the 8k-ish peak I saw at 100 ohms. If it can't be flat, I'd prefer the peak above 10k, where it mostly impacts "air" and not as many musical timbres or fundamentals.
Sorry, I probably shouldn't keep questioning you, I do think it's very cool what you have been presenting so don't think otherwise, but could you provide more detail on that model prediction, I'd think any electrical resonant peaking would be far far above the audio band with the tiny inductance involved here.
You can plug the inductance and resistance numbers into a simple version here, go to the MC section. Be sure to convert uH to mH. 2uH = .002mH Or 2.5 uH = .0025mH (if you really the manufacturing tolerances are accurate to half a uH). It moves even more into the midband if you use the 2.5uH number, dropping the peak down to about 6.3 kHz. The model isn't flawless in predicting real world behavior, but from my tests, it's not usually super far off, either.
I think it's mislabeled. The formula matches Matlab circuit simulators and empirical tests I don't use the web version, but the Matlab version. But, regardless, it's just a model. The real test is to do you own frequency tests with your specific cart
OK, but if you just plug the numbers in the formula for inductive reactance, you can see the scale is correct, the bandwith is over 6MHz with the 100 ohm load. But anyway, like I said, cool charts, thanks for posting them.
Then skip the models and just test it with a frequency test sweep rip and RTA. Empirical results are better, anyway.
Update, Just turned 59 hours on the ART9XA. The sibilance found on the beginning tracks of some LPs is gone. I had been running at maximum VTF (2.0g) which cured it right away- and is part of the break in process. Running at 2.0g does affect the bass- becomes somewhat dominant and unrefined. It is definitely sensitive to VTF. Unloading to the recommend 1.85g and all is well. The sound is better than out of the box and is enjoyable to listen to. Detail , high end extension and tone are excellent, I have never heard a cartridge reproduce cymbal kits with so much realism and dynamics. Bass is very good and there is just enough midbass warmth to call this one warmer than neutral if that is what you like. Midrange is sweet and colorful. I love the sound of music played with this cartridge. Final settings- 64db gain 200 ohms loading 1.85g VTF VTA= 0.5mm tail up.
Last night I listed to 45 RPM reissue of Fleetwood Mac "Rumours", which I don't think of as audiophile material, but the drum kit was attention getting.
My settings are almost identical. Loading is the same 200 ohms. VTF is 1.8g. VTA is currently neutral, but the cart is still <20 hours.
I was able to pick up a Cinemag 1254 1:10/1:13/1:20/1:40 SUT from Nclayton and it arrived yesterday. The ground lift is easy and perfect and the box sounds great. So glad I ran across your comment!
Ah, great. Someone wants to buy a used ART7 . It's from april 2020, just before the XA was launched. Nah, just kiddin'. However I'm curious about the bass response with the Shibata. Output is no issue here. Plenty of volume and no noise here. And no loading needed with the design of my Phono-amp. (The cartridge is it's own loading)
I don't know if it is because of the change to a Shibata cartridge or other factors, but the upper to mid bass seems different. It's hard to measure, but it sounds like the Q factor increased. I would have said the ART7 sounded like a 0.5, and the ART9XA sounds more like a 0.7.
Interesting... My ART9XA seems to have, or be capable of, a bit higher output than it is rated for. Enough to cause clipping with extreme dynamics of the phono input stage when the sensitivity was set to 0.2mV. Increasing the input sensitivity to 0.3mV has solved the problem, the cartridge now just kissing clipping on the widest peaks, but it's not often I've seen DR ranges this big on musical content, with peaks this sharp. MoFi 45 RPM of "Telegraph Road", MC input set to 03mV, Audacity set to full 1.0 gain. If I was archiving I'd probably dial Audacity back to 0.95.
Air-core cartridges are very fast, so that's not so strange. It's?about the recording/cutting. Is that fast enough? But clipping, that's odd. However my Phono-amp is not like any other brand, it's sensitive to 0,15mV but it won't clip until about 8V (yes, not mv, but 8 whole Volts).
Well, it's 45 RPM 12" record. It can't get any faster. 8V! That's a lot of headroom! Increasing the input sens by .1mV to .3mV solved the clipping problem. Of note, I didn't have this problem with the AT33SA.
That's sort of true. Yeah, I would put that amp up to every one's amp out there. A pitty that it's a local brand here in The Netherlands (so 230V). An AT33 is indeed about 0,3/0,4mV with 10Ohm but still 22µH. The ART9XA is 0,2mV with 12Ohm but as low as 2,5µH. Weird that it clips so soon with that output.
