Help with Turntable/arm/cart decision

Matt,

As I posted on your Woofer Pumping thread ten days ago, it's obvious from the symptoms that tonearm/cartridge compliance is not the cause. Your test confirmed this.

Have you performed the diagnostics I suggested on 7/21?

This problem is unlikely to fix itself. The most likely cause is a defective turntable drive system component - either belt, bearing or motor. The sooner you file a plausible report with the dealer/manufacturer, the more likely you'll get a satisfactory remedy under the warranty. The longer you wait, the easier it is for them to claim owner error or abuse and disclaim liability.

Matt, I just read this thread from top to bottom. I also saw the "woofer pumping" thread, but did not read it in its entirety. However, I have to ask an obvious question: where is your tt located with respect to your speakers? (I am sure this question was asked and answered on the other thread, because Doug would have also been asking about it here if that were not the case.) Anyway, on the off chance that you have not considered this, acoustic feedback from the speaker to the tt can certainly cause this sort of misbehavior. And even if the two components are not in obvious proximity, you might consider re-positioning either the tt or the speakers empirically, because quirky room acoustics can result in feedback even when there is no obvious reason for it. Further I would advise you to figure out your basic problem before installing your new REL woofer, lest you blow another one. You mention that the driver pumping has some sort of periodicity to it. I assume that by now it is established that the pumping only is observed when you're playing LPs, not with other music sources. Have you listened carefully to your new tt, to determine whether it is making a periodic mechanical noise of some sort? (This is what Doug was getting at.) One worthwhile experiment would be to install a different tt/tonearm and observe whether you still have the issue. That would indicate a problem with our new tt. Perhaps you still have your old Thorens or you can borrow a tt from a friend.

You already verified that the table is the problem. What makes you think a new phono preamp will fix it?

No , I never verified the new table was the problem. Not yet anyway. More to come on this soon. Lewm you are right on track with whats going through my mind as well. I really think I have more than one problem happening here. I will know a lot more here soon. I will say the table has a very heavy dust cover that I can take off. With the cover on I would think that would help a lot with any air born resonances wouldn't it? My system is rather close together. I am going to move some stuff around as you suggest. Regards,

Matt

How have you been playing LPs? Cover on or cover off? If cover has been on, take it off. If cover has been off, try with cover on, but I usually find that overall I like the sound best when the tt is naked, no cover. Others don't always agree, however. First of all, do change the position of the tt in the room OR move the speakers. I, like Yogiboy, do think that the info you've provided exonerates the phono stage, unless there is some unusual electrical oscillation going on. This could be the case, if the RIAA correction circuit relies upon negative feedback, but the possibility is very remote. I have a hunch the solution to your problem will prove to be simple.