AudioTechnica

Calibrating My Audio-Technica AT-LP60

I don’t have a ton of vinyl records, but I do like to actually listen to them. It’s a topic for its own entire post, but I don’t collect anything for its “value”. I collect because I want to enjoy it. I point this out a bit because I also have a shitload of toys. I noticed something recently, that I am surprised I didn’t notice before, or maybe it just, didn’t actually click that it was an issue. Last week I got 1989 (Taylor’s Version). While listening to that, everything seemed, slightly too fast. I think I may have noticed this a bit with my Bone’s 10th vinyl as well. In the case of the Taylor Swift album, I decided it was just something to do with it being a re-recorded album, and not a straight remaster/release.

More recently, I got my copy of Aurora’s All My Demons… (Commentary here)…

Because I started hardcore tracking my listening with Last.fm years ago, I can say, with confidence, that I have listened to this album a lot. I can’t say it’s my most listened to album of all time for sure, but I can say, it’s the top since I started tracking. When listening to it, things were definitely off. The whole thing was running slightly too fast, and Aurora’s wonderful vocals sounded weird.

My first thought was, that maybe the belt was wearing out. It also occurred to me, that it’s a belt, it probably has a tension adjustment somewhere. I looked up a copy of the manual, which didn’t mention it anywhere. But, various audio forums did mention it. On the bottom of the players, are two small holes, where a screwdriver can be inserted and the tension adjusted, altering the rotation speed.

The problem then was, how to know if the speed was right. I probably could have done it by ear with All My Demons, but the adjustment is on the bottom, I can’t adjust it while it’s playing (well, not easily). It turns out, there are technical ways to do this as well. One of the search results mentioned a printable strobe guide. I’m not positive what this is, but I can infer based on other things I know of. I suspect it works like a Zeotrope, where you get a sort of animation going when the record spins at the proper speed.

Another result suggested an app called RPM Speed and Wow. As the name suggests, it uses a phone’s accelerometer to measure the RPM and Wow of a turn table. I’m not entirely sure what Wow is, it seems to be related to audio distortion, I may look into that later a bit more. For now, the concern was the speed. I loaded up the app, placed the phone on the turn table, pressed the “pause” button on the player, which prevents the arm from dropping, but not the table from spinning, and pressed play. After about a minute, I had a measurement of 34.99 RPM, almost 5% off.

Suddenly it makes sense why all the music seemed too fast, because it was!

I dug out a small screw driver and carefully lifted the player up to turn the knob. One issue was that I wasn’t sure which direction to go. I went with clockwise (Spoilers, the correct direction is counter clockwise). I tested again, but it didn’t change. I tried counter clockwise, no real change. So I went and got an even smaller screwdriver.

Left Screwdriver was too large to fit, the right was needed.

It takes a very small screwdriver to get in the hole properly to adjust the knob. Also, it takes a very very very small amount of turn to adjust the speed. The best way I can describe it, I needed a 5% change, which pretty much meant a 5% turn out of a whole circle. I doubt it’s actually that exact, but it’s very very slight.

Anyway, after going Clockwise, things got faster, so I lifted things up and went counter-clockwise until I landed on 33.12 RPM. This is around half a percent too slow, which frankly, is close enough. Probably as close as I am going to get without seriously altering my methods. For one thing, during at least one tip to adjust, the turntable itself fell off, so I had to put it and the belt back on, which probably screws up these small adjustments I’m making as more than half a percent.

I put my All My Demons record back on the turn table and fired it up, and it was better, much much better, enough that it wasn’t noticeably off.

Just as a quick wrap up, I want to give a shout out to this Matco screwdriver set. A friend of mine in High School gave this set to me for my birthday, I think my 16th. His dad worked for Matco and there were a ton of Matco tools in his house. Anyway, it’s served me well, repeatedly, for over 25 years now. It’s a super useful set of screwdrivers (the pen not so much, I’ve never used the pen).