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My Garrard Lab 80 Obsession

gary7 said:
How can I narrow it down since it seems to be from the head shell all the way though the wires to the phono cables?
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I sooooo want to get new RCAs for my unit but most new RCAs' housings make them too fat because the receptacles are so close together. Sorry for being a bit off topic.
 
What cartridge. The LAB 80 for some reason was a bit cartridge sensitive. Some cartridges from Pickering, Stanton, ADC, B&O and, others had a ground shunt strap that bridge from one of the gnd terminals to the cartridge body and we found using them for the 80 reduced to eliminated the hum. These companies used the metal body for sheilding and the strap grounded it. On other tables using the strap either had no effect or induced hum and the sheild had to be lifted from ground.
 
Brian said:
What cartridge. The LAB 80 for some reason was a bit cartridge sensitive. Some cartridges from Pickering, Stanton, ADC, B&O and, others had a ground shunt strap that bridge from one of the gnd terminals to the cartridge body and we found using them for the 80 reduced to eliminated the hum. These companies used the metal body for sheilding and the strap grounded it. On other tables using the strap either had no effect or induced hum and the sheild had to be lifted from ground.
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I was using a Shure M80e first, This was original to the TT. I fiddled with the head shell and got it to where the hum was only notcable when you turn the volume way up to about 2:00 position. I thought it might be the cart, I tried my AT LS500 on it with a head shell from a project Type A II I have, same thing bad hum in both channels with volume about 9:00. Played with the shell, finally got it to one channel. Running out of ideas & a little desperate, I thumped the shell with my finger. Hum subsided as before, have to turn it up to notice it. Played a record, hum started again. Thumped it again, hum stopped. what gives.:scratch2:
 
You obviously have a bad connection somewhere in the signal or ground chain. You need to use an ohmmeter to measure the resistance from the ends of your RCA cables to the cartridge connections whilst you, gently, wiggle the various wires. This means 4 measurements. . .4 cartridge pins to 2 RCA cable with 2 contacts each (the center pin and the outer shield ring).
Rick
 
Agree problem seems to be intermittant contact. From memory I seem to remember there are spring lead contacts to the headshell at the arm. It might be that these over the years have compressed. If my memory is right, you may want to CAREFULLY see if you can rebend them out just a bit. It might also be a split in the wiring in the arm near the gimbal that is not uncommon with older tables over the years. If so, then it will require an arm rewiring. Not impossible but an interesting challenge. You'll need to find wires specifically for arms. Not uncommon from specialty outlets that support turntables.
 
Is the ground lead hooked up and making connection to the tonearm? Does it hum with the wire unhooked ? My 80 hums with it hooked up, but I have a metal body cartridge on there which grounds the tonearm and headshell through the strap on the L- lead. With a plastic body cart, you'd need to have the ground lead hooked up, but possibly not with a metal body. If you're using a plastic body cart that doesn't take care of the tonearm grounding, I'd bet you have a problem with the connection between the ground lead and the tonearm, or a poor connection between the headshell body and the metal strap on the bottom of the arm. Try cleaning the spot where the headshell and tonearm meet at the lock screw first. If thats no help, and you determine that theres a problem with the ground lead, I believe the ground lead attatches somewhere in the pivot area under the cover, but I won't swear to that. I can tell you with certainty that if you pull that tonearm pivot apart, you'll find a bunch of little ball bearings in there that like to vanish. Be extremely careful if you open that up. I lost some of mine and had to source replacements. Its a common size, and available in large quantity for cheap at mcmaster-carr but they're a PITA to get back in that cup.
 
I unhooked the ground wire from the amp and yes the hum about blasted the speakers out. With the ground wire the hum is not apparent until the volume knob is about 8 to 9:00 position, which is way higher than my listening level, the head shell has settled down now so if I move it does not go off the hum chart. The green ground wire on the unit runs from the motor to the bottom of the metal plinth. There I attached a wire to the screw and ran to my amp. I wonder could it be loose at the motor. Damn Hum Gremlins! By the way, since the wood base is just a shell to support the table, any suggestions on what feet I might put on it to raise it a bit so the it won't sit on the cables coming out from under it? I see holes at the ends of each side bottom that my have had some kinda feet.
 
The stock feet, or what I assume to be stock feet that are on mine, are simple rubber feet, about 3/8" tall by say 1/2" round. You can get something similar from any hardware store. I have no idea where people get those groovy adjustable height feet, but I'd like to know.
 
Well, I've been living with my Lab 80 for a little over a week now. The hum issue has seemed to subsided. I am really loving it. I think I like it better than the Dual 1219 I was using. About the only issue now is that the auto return does not engage every once and a while. I am using a AT LS500 now & it sound really good. Any other cart recommendations?
 
make sure the velocity trip linkage is absolutely clean. Its the white plastic lever underneath that moves with the tone arm. I had to take mine off and swab it and the pivot point with rubbing alcohol in order to work right. There is also a height adjustment thats a bit finnicky. Too high and it rubs the stop cam on the big drive gear that works all the linkages, and that will prevent it from moving right. Too low and the magnets dont line up enough to work right.
 
Please don't whip me. In 1967 when I was a junior in college I went to buy a turntable at Musicraft in Chicago. The Lab 80 was sitting next to a Dual 1019. I took the Dual. In my demos it appeared the Dual was head and shoulders above the Garrard in mechanical workmanship and operation. I still have it today.
 
He's 100% right ---Don't touch that height adjustment screw--UNLESS you are SURE it is the problem. I don't think it is ---I just think your a little gummed up.
I had the same issue with mine.
 
I found back when the LAB 80 was in production when mated with a synergetic cartridge, it better the Duals. It's main deficiency was the arm appeared like a tire iron compared to the Dual though it was far from it, and the resonant frequency was actually lower. I used a B&O SP-10 initially and then moved up to a SP-12 back then. The Dual did not do as well with them. In my pecking order, my preference as a general rule has been the Miracords, then the Lab-80 and later Zero 100C, then a tossup between the PE and Dual but tended to like the PEs better until hitting the 1219 and 1229 Duals. PE over here and Miracords were harder to find as their distributors were either changing or nonexistent and later when Miracord and Radio Shack teamed up the Miracord became almost persona nongrata in "real" audio salons. The MIracord 750, 50 and 10 series were really great. I really think of them as automatic turntables rather then changers that could convert to a turn table by replacing the spindle.
 
I had a Lab 80 in high school - I moved up to it from a Model 50 - my first "new" Garrard! I loved that "80". Don't even remember what happened to it - I dabbled with a few Rek-o-kuts before I bought a brand-new Empire 598 (still have it).

I scored a Type A - I always loved the look of those - so my Garrard "fix" has been satisfied with a model which is older than any I owned "back in the day!"
 
jlovda said:
Please don't whip me. In 1967 when I was a junior in college I went to buy a turntable at Musicraft in Chicago. The Lab 80 was sitting next to a Dual 1019. I took the Dual. In my demos it appeared the Dual was head and shoulders above the Garrard in mechanical workmanship and operation. I still have it today.
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I have both the Lab 80 and a Dual 1019 hard to say which one I like better they both are amazing. Currently using the 1019 on my main system. The Lab 80 is eagerly waiting it's turn on the bench for a detail.
 
I got my LAB 80 at an antique shop and it was obviously VERY lightly used.
I noticed a slight wobble in the pitch after having it for a year (not sure what took me so long to notice it...maybe it wasn't always there??). It is more noticable on the last track on a record side.

I verified the speed hiccup with a stroboscope. It appears to be once every revolution. The marks on the scope slightly drift backwards (I could live with that, if it was constant) but once a rev, they jump back as if something is rubbing.

Here is the situation:

- I have the spindle oiled with light sewing machine oil,
- I thought it was a warped platter, so I bought a second platter for cheap to test...nope...still hiccups.
- The inner rim surface (where idler contacts) was cleaned with alcohol.
- The main bearing is in excellent shape and properly assembled (i.e. the upper and lower thrust plates are where they should be, the balls are in place and the plastic bearing housing is flawless.
- The idler wheel shows no signs of cracking or hazing and I have rejuvenated it and filed off the outer surface to expose new rubber. It also gets up to speed in about 2 seconds, so that tells me the wheel is acceptable. (not that I suspect an idler wheel or motor problem because the hiccup is once per platter revolution)

I really dig this turntable. My PL-41 is in storage because I prefer the LAB 80 with Shure M91E as my daily driver. I'm just bothered knowing that the hiccup is there...I'm sure you all understand.

Any suggestions would be appreciated.

Thanks,

JD
 
I got a Lab 80 pretty cheap but the idler intermediate wheel does not seem to want to move the platter round. Motor seems ok and engages with the wheel when the platter is off. Any ideas? Does the intermediate wheel need changing?
 
It could still be the idler wheel. You will not really know until you try another. My lab80 had a similar problem and the wheel looked ok to me. A rebuilt idler wheel solved my problem.
 
It's hard to believe that it could be anything other than the platter, given that is hiccups once per revolution. Is it exactly once per revolution, or does it move around? It could be that there is a defect in the idler that interacts with a slight runout on the platter. I guess your only option at the moment is a rebuilt idler.
 
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