Curved arm?

[Aquateen]

What's the official name for those turntables with a curved arm? I'm pretty sure they're used for radio but I want to know what the official name for one is.

[BradOlson]

S-Curved tonearm.

[Sckott]

Yep. Not necessarilly made for radio. ;)

[BradOlson]

I myself use an S-Curved tonearm.

[proufo]

S-curved tonearms aim at having an axis of balance in the pivot-headshell line.

Superior in that respect to j-shaped ones.

[BradOlson]

Most of the turntables we sell at NorthernLightFX are S-Curved or straight arm. The straight arms do not need any Anti-skate features. For you Grado fans, we are looking into carrying your product as well. I have suggested other lines of audio product to my employers as well based on what Acoustic Sounds carries

[JoelDF]

My old Fisher TT from the early 80's has an S-curved tonearm. I remember S-curved and straight tonearms were pretty much 50/50 back then with component stereo systems.

Joel

[sgraham]

Pivoted straight arms (as opposed to linear tracking arms) with *no* offset are made explicitly for "scratching", and are definitely not recommended for anything else. The offset greatly reduces tracking error (that is, it keeps the stylus much more nearly tangent to the groove across the entire playing surface).

[Grant]

Sgraham,

If it recduces tracking error, why are they not recommended, and why don't "serious" turntables no longer use them? Mass? Resonance?

[Stax Fan]

Originally posted by Grant
Sgraham,

If it recduces tracking error, why are they not recommended, and why don't "serious" turntables no longer use them? Mass? Resonance?

A straight tonearm without offset exhibits underhang and is the one not recommended for ordinary use. A straight tonearm with offset exhibits overhang and is the one that substantially reduces tracking error. Straight arms without offset have a much higher tracking error than those with offset. Offsetting a cartridge on an arm without offset doesn't work. This will improve tracking over a corresponding area of the record, but will reduce it over the opposite area. Like Steve says, not much use for straight arms without offset other than scratching. They're great for enhancing the stability of the stylus in the groove, but the trade-off is increased record wear and distortion. :)

[sgraham]

I'm sorry if I wasn't clear.

All serious audiophile tables use a pivoted tonearm with an offset of some type, whether via an S shape or by simply angling the cartridge mounting; or else they use linear tracking straight line tonearms, in which the rear of the arm moves on a track to keep the stylus tangent.

Straight *pivoted* tonearms with *no offset* are not recommended because they increase the tracking error. THey are useful for "scratching" because the lack of offset equalizes skating forces. With an offset the stylus is more likely to skip.

What Arin said.

[Grant]

I'm about to ask a stupid question, but what exactly is the offset? On my table, I have the tracking force counterweight and the anti-skate control. What am I missing? I have a straight arm. It is mounted in a way that does not pivot, like, say, a Music Hall table. Huh?!?:confused:

[Stax Fan]

NOT a stupid question at all. If you're looking down from directly above the tonearm, the offset is just the angle of the cartridge relative to the tonearm. Notice how the headshell where your cartridge is mounted angles inward towards the spindle? That's the offset...for a straight tonearm with offset, anyway. I've never owned an S-shaped arm, but judging from what Steve said, the offset for those is introduced through the shape of the arm itself instead of the angle of the headshell...which would make sense.

[Grant]

Oh, OK. Yeah, it has an offset. I don't think i've ever seen a pivitod straight arm without an offset.

[sgraham]

The only pivoted arms with no offset that I'd seen until recently were the huge old klunkers made by RCA to go with their transcription turntables for professional use (1940's). THose were made to play 16" disks, and they were so long that I guess they didn't figure it was a problem.

Some months ago I was shocked to find some Stanton turntables at a musical instruments shop that had short, straight arms - I couldn't figure it out until I realized they were intended for scratching.