In article . com, max
graff wrote:
Hi guys,

I am a newbie turntable user and have a question for you.

Each time I start or stop my turn table mechanics with my amp still
powered on I see my woofers giving a low frequency boom. This is guess
is the sound picked up by the tone arm etc.

I can actually see my woofers breathing in and out when this happens.

You do not say what turntable or amp you are using (nor amp or cartridge).
What you describe seems quite unusual to me. It should not occur. Not
something I've ever encountered with various systems I've used.

Assuming that you are *not* leaving the stylus on the record at the time...

Do you think I am #@$king my speakers up, should I turn down the amp or
pull the volume down before starting/stopping my TTable? Or should I
just not worry?

It would concern me. The obvious avoidance is to wind down the volume
level. Or to switch to a different input. However I would then certainly
regard this as a 'fault' and try to fix it. Difficult to know if it will do
any damage as we don't know enough about your system.

Does you 'turntable' happen to include its own (RIAA) pre-amp for its
cartridge, and you then connect into your amp via a line-level input? That
is the only possible cause that immediately occurs to me. If so, it may be
that the amp built into the turntable is being switched on and off, and
this generates a LF 'thump'. If so, it is a poor design, or is poorly
matched to your amplifier, or there is a fault.

Given more details of your system it may be possible to identify some other
possible reasons.

Slainte,

Jim

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