|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
73.173.151.186
Curious here on this question please,
Was talking to the local audio shop and told them I was going to pick up a ortofon red from them and they said they would set it up but told me I might need to get a new counterweight for the ortofon beings it is a Music Hall MMF-5 turntable(older model) has anyone ever heard that before? I have posted before and if it was needed I thought someone would have told me about that being an issue just checking if anyone would know figure someone here would.
Thanks,
Kindablue
Follow Ups:
It's possible that balancing the cartridge is not the problem but that with your counterweight you end up with an effective mass of the arm/cartridge producing a arm/cartridge resonance either too high or too low for best performance. If that's the problem, your dealer should explain it to you. It's never bad paying for something real if it's made clear.
My calculations indicate that for more-or-less traditional arm configurations the counterweight contributes only 4-5% toward the effective mass. We have to be careful to separate the concepts of mass and VTF, noting (carefully) that effective mass is that which affects arm-cartridge resonance. The counterweight is there and it's massive, but it has only minor **participation** in the cartridge dynamics.The bulk of effective mass (90%+) comes from the cart + headshell (> 75%) + armtube and the polar moment of inertia ( <20%). So, basically, all a counterweight has to do is establish the correct VTF, beyond that it's effect on cartridge dynamics is nearly negligible. As far as the sale of expensive custom aftermarket counterweights, people put expensive, custom rocks on their electronic equipment cabinets and funny little hats on their vacuum tubes too. Doesn't make these good ideas.
On a side note, as a structural dynamicist I decry all "rubber donut" isolation schemes in any part of the tonearm. They don't provide meaningful isolation, they introduce a spurious nonlinear element into the structure of the arm/counterweight which must dissipate the energy of the mechanical vibration that the cartridge throws up it, and the rubber parts fail in time.
Edits: 05/16/17
Why would you need a new counterweight?
The old MMF-5 came with a Goldring 1012 GX cart that weighs 7.6 grams and the Ortofon 7.2 grams making for a .4 gram difference.... surely that's not enough to warrant a new weight?
Now you know why you should always set up your own turntables!
At any rate, I would never let anyone else touch one of my turntables.
Good luck,
John Elison
That Ortofon weighs 7 grams. That is not a super heavy cartridge. I doubt you will have any trouble balancing the arm without any new counterweight!
Well when I said I was going to pick up the cart from the shop and was talking to the guy and he said we could put it on and set it up then he mentioned that "as long as it don't need another counterweight" I had never been told that before on just changing carts so I figured I would put it out there. I don't have a big problem with someone putting a cart on the table but when it comes to changing my weight I do get worried so I figured someone here would have an answere. I will go over there with the info I have got and see what they say and go from there.
Kindablue
There will be no problem with that cartridge on that arm.
Yes that is what surprised me about even bringing it up but figured I would post just to get a better understanding in case I missed something in the past 20 years.If they say anything about the weight change I will just take the cart home myself and set it up.
Kindablue
If the cartridge that you're contemplating is heavier than the maximum specified by Music Hall for its tonearm a heavier counterweight would be the best way to make the combination work.
Either that or add lead tape to your present counterweight.
Cheers,
SB
Thanks billy, guess they are just looking out for my table the weight is only 49 bucks we will see. Although it will take a week to get it IF they have to order it.
Kindablue
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: