Audio Technica AT150MLX finally gets some respect


I've been at this audiophile stuff for over 40 years. At this point I'm pretty confident of being able to ignore preconceived notions and evaluate the strengths and weaknesses of a component in my system. Still, once in awhile it's nice to get some validation--a sanity check.

I've been using an Audio Technica AT150MLX MM cartridge for over 3 years. Since getting it I have improved the downstream components and cabling a few times, and each improvement, rather than revealing limitations of the cartridge, has shown it to have a great tonal balance, high resolution at its price point, excellent trackability, low level detail retrieval and excellent dynamics.

Still, when I opened my January 2012 issue of The Abso!ute Sound, I was pleasantly shocked to see that the $449 list AT150MLX had been named Cartridge of the Year! Given that the $5000 Benz LP-MSR and $13,000 Clearaudio Goldfinger were also mentioned on that page, it wasn't that the AT150MLX won in absolute terms, but for performance value.

It's as I suspected from my first listen. If you want to know where the threshold into a high end cartridge is, it's the AT150MLX. I got mine in 2008 when the dollar was strong and these things were going for $250. But even at the currently available $325 they are pretty unbeatable.

Back in the Spring of 2008 I asked the A-goners about what cartridge to move up to from the DL-160. I was considering the AT OC-9 or the Denon 301 II, but a number of A-goners made a compelling case for the AT150MLX. I took them at their word and have never regretted it.

If you want the best out of this cart, you *must* give it a capacitive load between 100 and 200 pF. In fact, my highly adjustable Jolida JD-9A phono stage indicates that the real sweet spot is right around 150 pF.

Anyway, thanks A-goners, and it's also nice to know that when the stylus wears down, I can just send for a replacement plug-in stylus $225.
johnnyb53

12-16-12: Dconsmack
I've found to achieve a flat response (+/- 1.5dB) you have to load it at 15kΩ impedance (yes!) and around 570pF total capacitance.
Since my phono stage is pretty configurable (Jolida JD9A), I got all excited and looked at the manual to see what all my DIP switch settings are. But alas, I can set a range of small increments from 100 up to 1400 ohms, but then it jumps to the ubiquitous 47K with nothing in between. Maybe my speakers roll off gently enough above 10Khz to work well in my system. What speakers are you using? I can see where if one were to have ribbon tweeters or something very linear out to 20KHz, that your approach would improve the high treble. Or it could be that I've become accustomed to a treble rise and don't know what i'm missing.
If your speakers roll off above 10kHz, then you likely don't hear the treble rise, or it sounds balanced. I can absolutely hear the difference between 47,000Ω and 15,000Ω. Also, CDs with the exact same mastering as it's vinyl counterpart consistently shows that 15,000Ω is neutral with the AT150MLX (and lots of capacitance: 570pF). Also, I found it to be superior to the OC9 II due to better tracking of sibilants and flatter response. Initially it sounds dull, but that's because so many modern cartridges have a significant rise in the treble. Actually, the only carts I've ever heard that don't are the Shure V15VxMR and Dynavector 17D3. Even the 17D3 has a small rise in the treble, but it's very minor. But, time after time, comparisons with CDs of the same mastering proves to me that the AT150MLX loaded that way is nearly identical in tone. And, it has a noticeably wider stereo image than the 17D3 and the V15VxMR. The 17D3 might be the king of tracking the absolute most difficult sibilants, but the AT150MLX tracked some sibilants that the V15VxMR could not. I really think that the AT150MLX might be the ultimate cart, it's just too bad almost every phono stage on earth can't load it properly. I got lucky.
Interesting inputs from Dconsmack. Johnny, given particularly that the 150MLX is a high output cartridge, a reasonable approach to implementing the loading he suggests might be to use a y-adapter, preferably a "hard" adapter such as this one from Audioquest. You would then solder an appropriate resistor to an RCA plug (and a capacitor as well, if necessary), and insert that plug into one of the two female connectors on the adapter, with the phono cable of course connected to the other female connector.

As I'm sure you would be able to calculate, a 22K resistor in combination with the 47K input resistance of the phono stage would result in an overall load of 15K.

Regards,
-- Al
If you do this, remember to have your total capacitance be 570pF or a little more. Otherwise it will sound dull due to a dip under 10,000 Hz. The 15k ohm/570pF total capacitance was the formula I was able to come up with my gear that yields the most accurate frequency response, both measured and with listening. The Ultimate Analogue Test LP was an invaluable resource in knowing what combination of impedance and capacitance to load all my carts.
I can hit the 570 pF with my Jolida without modification. 100pF in the phono cable plus DIP switches that can add 220, 150, and 100 pF, which all adds up to 570. Yay! If I do the Y-adapter mod to get a 15K ohm load I'll check it out and report back.