Upgrading your AT-LP120 turntable

Glad to help!

Go to the following link:

http://conradhoffman.com/TemplateGen.zip

Download the program, unzip it and run it.

Enter the following values:

Pivot to spindle distance = 214.500
Inner groove radius = 57.5
Outer groove radius = 146.05

Finally, choose Stevenson A alignment.

You will wind up with the most accurate protractor for the AT-LP120. Hunting down that official pivot to spindle distance was a bear, I can tell you. Once I had these figures and printed the protractor, my days of adjusting my cartridge were over.

 

DarkAudit, the method I just posted above is better than the alignment tool. I discovered it long after starting this thread and never thought to add it.

 

Hey, anyone who reads this thread, ignore the first post and go to my updated blog, which has the benefits of a few things I learned later.

http://scouringthebins.blogspot.com/2013/03/tweaking-audio-technica-at-lp120.html

 

You could always mount RCA jacks in the back, cut the cable, hook one end to one pair and one the other. Install RCA jumpers for built in preamp or hook direct for external. I believe a buyer could be sold on this upgrade.

 

They probably could. Problem is that the internal preamp in this thing is really horrible. For instance, mine would cut out completely at low noise levels ... I don't know if that was meant to be a "feature," but it was pretty disconcerting and of no use at all when needledropping. It's why I switched to an external preamp in the first place!

 

I finally got the nerve to yank the preamp out of mine, and I've never looked back. It's more versatile than the SL-D2 I have (still need a 78 cart ), and makes for a better photo when I've got something playing.

 

Restoration of 78's is all about the stylus, and while there is no "one size fits all" for shellacs, the Shure M78S will work for most, and give you a good bang for the buck.

 

I agree, but RPhelps didn't want to trash it and I thought it would be fun to do a different kind of mod. I ended up snipping the factory cable from the preamp and soldering to some RCAs then installed a switch so as to make the preamp still usable. Thoughts?

 

I like the idea of snipping the factory RCAs and putting those RCA jacks in, but I would have still eliminated the preamp because of the reasons mentioned in this thread. Still, nice job on the jacks

 

Yeah, I can't fault the handiwork! Nice job!

 

Just wanted to say thank you OP! After reading this thread and watching the videos I finally got up to tearing out the internal preamp this week with some help. I purchased the Little Bear Tube preamp and am using that. I still can't get over the increase in sound quality, it's seriously a night and day difference. The highs especially are much more clear, less muffled. Thanks again!

 

I made a new topic for AT-LP1240-USB, still need help determining the color routing to RCA.

 

Has anyone tested a modded LP120's specs against the published ones? Or an unmodded vs. published for that matter? I've got the PlatterSpeed app for my iPhone (without the purchased wow addition), using the 1kHz signal from the NAB test record, and the lowpass-filtered frequency result is plus or minus 0.02%. If that is the number I should be looking at, then I'm good, right?

OTOH, the raw frequency number is plus or minus ~0.45%.

 

If anyone can answer this, I'd be interested in knowing as well.

 

I got the WOW addon for PlatterSpeed and ran some tests. Using the 3kHz test tone off of the NAB Test Disc. Receiver is Technics SA-600, speakers Technics SB-G400. Cartridge M97xE with JICO SAS stylus. First is the SL-D2 I already had connected:


And now the LP120. 5 o-rings on the tonearm, KAB Supermat in place of stock slipmat, preamp board removed:


Back in the day, the SL-D2 was rated at 0.03% WRMS. Has age caught up with that one?

I'm not an expert, and the tests weren't under perfect conditions. Someone with more knowledge care to help interpret all of this?

 

A few factors are probably conspiring. Technics was maybe a little generous with the original published number; whatever test they used was very kind, inaccurate, or both. And I definitely believe a 35-year-old unit won't be within factory spec anyway. Also, you have to play the test tone out a speaker and into the mic on your phone, right?

From their website:

Still, it looks like it holds its own against your AT, and that is presumably new! Says a lot, really.

My question is, why are both of them seemingly playing fast? 3016 and 3017 average frequency?

 

Good question, especially since the 1kHz signal is nearly spot on on the other side of the record...

 

Just thought I'd mention that I just removed the preamp to my Audio Technica 120.....but I don't dare test it until AFTER I've watched Miracle on 34th St. with my wife...lest I ruin her chance at that warm fuzzy feeling. Lol. Hopefully,I didn't butcher the re-wire job. My eyes have been atrocious of late. In about two hours I'll know if I succeeded or failed.

 

Nice seeing this discussion on the AT LP120. Just bought one a few days ago and it is sounding good overall. I do have some questions regarding some mechanical noise coming from the engine (click clack noise like the ball bearing isn't lubricated enough):

1. If I change the mat will it improve this click clack noise (really low, but still present) I get through the speakers - obvious especially while in the groove in between songs.

2. Would yanking out the preamp help with this?

3. Has anybody thought about trying to oil the ball bearing somehow and how would that go and with what kind of oil?

Besides these noises which to be honest are annoying me just because I know they are there and not necessarily because they influence the music quality, the TT is running great.

 

Just wanted to post my sentiments about the AT-LP120. I've followed the advice on this and other forums and really like the results I'm getting from this turntable. I removed the phono stage, purchased the upgraded counterweight, and upgraded the cart to an AT-120e. I'm currently running the table into a Bugle2 phono stage and my NAD reciver which drive some full range speakers. I'm more than satisfied with the lovely sounds and my respect for the finer qualities of listing to Vinyl has been re-kindled.

Cheers.

 

George,

You might want to look into getting your turntable replaced or repaired depending on which options you have open. I can't hear any such audible noise that can be attributed to the motor or other mechanics of the turntable. You should look into that before removing the preamp which would void your warranty. It is possible that you may be hearing static or dust which tends to be more of a problem in winter when there is low humidity.

 

I have to echo that. While my AT-LP120 has slight motor noise ( an unfortunate side-effect of a lower-end direct-drive table), there's no kind of click-clack whatsoever.

 

Just pulled the trigger on the counterweight and re-re-realigned the cartridge. Baerwald this time. Mostly because it was the closest protractor on hand, and partly because I was getting a lot of distortion in the mids of some old albums.

(These were albums that were new to the collection. I haven't heard anything go wrong with any that I already had.)

 

Let us know how the Baerwald works out for you. I had noticeably better results with Stevenson A.

 

Thanks a lot for this thread. I have viewed it a ton of times. Finally have the turntable all done up. Bought it about a month ago and got it all setup. Works great now. The sound quality improved immensely with all your recommendations!