BeoGram

Re: Beogram 4002 distortion

Søren Hammer — Tue, 01 Dec 2009 05:40:26 GMT

Hello Menahem

I have contacted that technician who replaced the speed changing relay. He is saying that those plate weren't levelled when he did the repair. I have to send the turntable to repair with my BG 4000. Thanks for the advice :)

Re: Beogram 4002 distortion

yachadm — Sun, 29 Nov 2009 05:50:43 GMT

Soren,

I may have an interesting solution for you.

I remember that I had one of these turntables for repair a couple of years ago, and it was also distorting on only certain areas of the LP. I finally traced the problem to the 2 aluminium plates - the large one surrounding the platter, and the smaller one above the control panel.

They were not stting EXACTLY horizontally, and there was a small amount of friction between the plates, and the moving part of the arm.

It was caused by the fact that the chassis poles which stick up into the holes on the underside of the plates were not exactly aligned.

I solved the problem by taking a slightly larger drill-bit, and widening the holes on the underside of the plates - drill slowly and carefully, not to penetrate the platter's upper-side. Then the poles fitted into the holes perfectly, and there was no more distortion.

Regards

Menahem

Re: Beogram 4002 distortion

Søren Hammer — Mon, 16 Nov 2009 14:33:24 GMT

Thank you for your response

I have tried several brand new records, but there is still audible inner groove distortion. A Pioneer Pl-223 with Ortofon OM5, I once had, would never produce audible distortion, and when I try my old and new records on my Father's Beogram 8002, there is almost no distortion at all.

-Søren Hammer

Re: Beogram 4002 distortion

AdamAnt316 — Mon, 16 Nov 2009 13:56:19 GMT

Actually, the problem may lie with your records themselves. Inner groove distortion can result from a record being played with a turntable which is not properly set-up with regards to the cartridge and stylus. Most, if not all, Beograms shouldn't have this problem, since the cartridge/stylus can only be mounted one way. Try buying a brand new record, and play it a few times with your Beogram, and see if you still get this effect. Hope this helps.

-Adam

Re: Beogram 4002 distortion

Søren Hammer — Mon, 16 Nov 2009 12:43:06 GMT

Hello, I still have the problem... The Turntable is audibly distorting about tho thirds though a record. It does that with my MMC20CL and MMC20S cartrigdes, The arms are still tracking 100% parallel, and the tracking force is set to 1,5g, which is the maximum setting, though I have tried everythng between .8 and 1,5. The turntable clearly sounds better when I increase the tracking weight. The Beogram sounds fantastic in the start of the record, and I suspect that the rubber suspensions og the cartrigdes are hard.

Do you think that the problem lies in the Beogram or the MMC20 cartrigdes? Just in case, as I am soon preparing to send the MMC20CL to Axel for refurbishing with a Shibata diamond...

Re: Beogram 4002 distortion

DSJR — Sat, 08 Aug 2009 07:03:46 GMT

These cartridges were temperature sensitive and should sound much better in clarity and tracking during the summer months. try shining a small spotlight on the deck, not close enough to risk damaging the lid, but enough to further warm the playing area under the lid, which the electronics inside the deck should help with too. Aim to get the cartridge up to 22 degrees C at least. It certainly worked on new 20CL's I found. I'm not sure if the re-builders out there change the suspension on re-tipping, and if they do, whether they use a more temperature-stable material these days. At least you can get the CL done to a beautiful standard by Axel, judging by the pictures posted.

Re: Beogram 4002 distortion

Søren Hammer — Fri, 24 Jul 2009 04:26:02 GMT

I tried to increase to 1,2. Much better, but there is still a very small amount of audible distortion, I might try 1,3 grams later

Thank you for the advice Martin ^^

Re: Beogram 4002 distortion

Dillen — Thu, 23 Jul 2009 15:34:29 GMT

1g sounds a bit low, even for a CL cartridge and you're right in assuming that the tracking force
scale shouldn't be trusted 100% anylonger.
Most original cartridges have hardened suspensions to different extents by now.
Try increasing to 1.2g or even 1.4g if for nothing else than the diagnosis.
If the cartridge is fine, it won't damage anything.

Martin

Re: Beogram 4002 distortion

Søren Hammer — Thu, 23 Jul 2009 13:40:36 GMT

It is tracking well

Arms are parrallel always

I don't have a stylus weight, but the MMC20CL is adjusted to 1 Gram, according to the tracking force adjustment window(I know it can drift over time)

Re: Beogram 4002 distortion

Dillen — Thu, 23 Jul 2009 08:40:18 GMT

Does it track properly ?
Are the arms parallel at all times ?
Is the tracking force set correctly ?

Martin

Beogram 4002 distortion

Søren Hammer — Thu, 23 Jul 2009 06:09:24 GMT

Hello, I am the lucky owner of a now fully functioning BG 4002. But I have a small problem: When the stylus gets closer to the center, the amount of unwanted distortion increases! At the last tune on record side the sound is horrible! It even does that with all of my new 180 gram records...

the stylus is an MMC20 CL which normally sounds fantastic...

Any help, please?