Cartridge/Phono-Pre Break-in?


I just installed a new Audio-Technica 150MLX cartridge and Cambridge 640p phono-pre in my second system (SL1200 table, Nuforce Icon amp, Gallo speakers), and after two days it sounds about like an AM radio...no highs, no dynamics. Computer audio playback sounds quite fine. I thought I might have a poor cartridge wire connection (suckers were tough to install without breaking them) but there's no hum or distortion. Does this happen? Do either of these pieces change dramatically with break-in?

Thanks for any guidance.

Jeff
jmudrick
I'm unfamiliar with your components, but all cartridges change with break in, some more than others and in different ways of course.

A constricted frequency range is very typical in a new cartridge. They often need some hours to open up, at both ends, so give it some time. How much? It depends. I've heard cartridges open up fully after just 20-30 hours and others that were still developing at 200.

Same for phono pre's, though the changes might be less dramatic than with a cartridge.

THINGS TO CHECK...

Constricted highs can be evidence of improper impedance loading. Make sure you're using the MM inputs and not the MC inputs (sorry if that's obvious).

Excessive VTF will constrict a cartridge's HF response and speed. Check yours with a decent (digital) VTF gauge. If you're using a Shure balance or something similar, throw it away. Good digital scales can be had for way less than $100, so there's really no excuse not to have one. Once the cart has 25-50 hours on it, try reducing VTF in .1g increments and see if the HF's don't come in. Just be careful you don't go too low and start mistracking, which would damage your vinyl.

Finally, excessive antiskate can sound like excessive VTF with many cartridges. Try reducing that too.

Be patient and start working at your setup. Unlike digital, analog playback is not plug and play. It requires work, effort and thought to get any rig optimized. Whether that's a part of the appeal or a royal PIA is up to the individual!
Doug's advice is good. However, it sounds to me like you have something terribly amiss. If it truly sounds like an AM radio, something, somewhere, is not connected properly. Cartridges and phono pre's DO require a break-in, but I've never heard ones that change *that* dramatically - somehting else is the problem...

-RW-
Another thing to check is the Vertical Tracking Angle (VTA). If it is too steep, i.e. the tonearm is tipped down towards the record, the sound can be profoundly tin-like. Too shallow, i.e. the front of the cartridge is tipped up, and the sound with be dull and soft.
I have an AT150MLX mounted on an SL1210M5G w/fluid damper feeding the MM input of a Cambridge 640P. I didn't install them together all at once; there was about 2-4 wks between getting the 640p and AT150MLX.

At any rate, in my system, both components sounded extended and musical right out of the box. The 640p was a little bright and edgy I suppose, but both were totally listenable from the beginning and sounded very musical and sorted out within two weeks of playing about 4 hrs/day.

I suspect something else at play here besides tough break-in, and the diagnostic suggestions so far should be chased down, esp. VTA, VTF, etc. What headshell are you using, and are you using the additional counterweight? What VTF are you at so far?

If you suspect your cartridge leads, maybe you should get a new (better) set and try again. You can get silk-wrapped OFC Litz leads from LPGear for $15.95/set.
DougD...Why do you think the Shure scale is no good...I think its perfect for us. I dont see the worth of the 100 dollar outlay at all.
Hi Stringreen,

It's been well documented on this and other forums for years that *some* Shure gauges were/are actually manufactured from magnetically sensitive steel. Think about what that means for accuracy when used in proximity to the powerful magnets in a phono cartridge. Even the non-magnetic Shure balances are pretty low in resolution.

If there were nothing better at a reasonable price that might be acceptable, especially for entry level rigs. But that's just not true any more (though it used to be).

Note that I said a good digital VTF scale can be had for "WELL UNDER" $100. You can get one here for $69 or on ebay for half that. Is $35 really a problem when we're trying to optimize cartridges costing 10 or even 100 times that?

I agree, BTW, that no scale will help us FIND the optimal VTF. Only our ears can do that, and each cartridge is indeed unique in this respect. No argument at all. A scale can only get you in the right ballpark. If it's a good scale it will do that reliably and repeatably. If it's a Shure, nobody knows...
Jmudrick,
I have an Audio-Technica 150MLX, and it is a pretty high compliance cartridge. As such, it should be used with a low mass tonearm. Low mass is not the same thing as adjusting the tracking force lighter. As I recall, it sounded very good out of the box, but improved a bit after 10-20 hours were on it. I am using mine with an Infinity Black Widow which is a very low mass tonearm, and I like it a lot.
If Shure made them from steel, there would be a problem. I have 2 Shure scales. One I've never used...just got it as a "bonus" when I got the 10.5i arm a couple of months ago. I checked that one with a magnet and my old one that I got about 1956 or so, and they both don't respond to the pull of a magnet. The new one looks like aluminum.. the old one looks like steel, but as I said it isn't magnetically sensitive.
Knumbskull calling. Rlwainwright was on the right track. It was the most obvious thing -- I had the damn thing plugged into the MC rather than the MM jack of the 640p. Duh. Should have been the first thing I checked. Well thanks everyone for your suggestions. Sounds fine now. I did order a Shure gauge and will see if there's any discrepancy of siginficance from the manual setup (initially at 1.25).
Jmurick..When you get your Sure scale, I found it very accurate if you position it on your turntable platter so that the front (right side when looking at the mirror) 2 feet are hanging off of the edge of the platter, then follow the normal directions.
Dear Stringreen: Doug is right about the Shure VTF gauge: I don't know when but Shure build some units that were magnetical active.

I like you are lucky because ( I own two too ) the ones that I own are right on target but there are others out there that there are not, the subject is: how can we know it before buy it?

Regards and enjoy the music.
Raul.
Just of of curiosity Johnnyb53, since we have the same setup (1200 with fluid damper, using a Zupreme headshell), where'd you land in terms of tracking force with the cartridge?
08-19-08: Jmudrick
Just of of curiosity Johnnyb53, since we have the same setup (1200 with fluid damper, using a Zupreme headshell), where'd you land in terms of tracking force with the cartridge?
I had it at 1.6g during break-in, and have listened to it at 1.4g ever since. However, I'm only going by the numbers on the Technics counter-weight; I don't have a VTF gauge yet.
Regarding magnetically attractive Shure scale. Thanks to those that revealed that some Shure scales are magnetically attractive. My advice is if you get one, test it with a magnet, and if the magnet attracts, return the scale.
Where's the best place to order turntable tools? I need to setup my TT and not sure where to find the tools.