Fine tuning the Evolution (Vic's) Ladegaard type arm

[Clive]

Is your pump a 2 or 4 output type. Mine's a 2 output so I have half the output of a 4. Either you have a more powerful pump or there's a variation between our aquarium valves, I don't get any noise from my valve.

Clive

[Paul Barker]

I was ignoring this thread because I thought you were on about transformer ringing which would be expected on a valve amp forum.

Anyhow I've read the thread and caught up.

My air arm is also being a nuisance. Also I seem to be the only one who sufferes end of record bounce back, nomatter what I do.

[Clive]

Hi Paul,

Yes my original "subject" was misleading, I've edited this now.

I have experienced bounce-back too but only on 78s so I don't know how relevant this is. I'm sure you've tried many things to fix your problem, all I call do is say what happened in my situation.

When the stylus reached the start of the lead-out area the rotational inertia was such that the stylus would come out of the groove and fling the arm towards the label. The stylus would make contact with the label and bounce back.

The problem in my situation is that I was tracking at only 2gms, increasing to 3gms solved the problem.

The issue probably isn't only about tracking force but also effective mass. I have 3 versions of Vic's arm, 2 have gimbal bearings with different weight bearing mounts, the 3rd one is knife bearing. I was using the lighter gimbal for 78s so out-of-centre records would place less stress on the cantilever. Probably this made the arm more sensitive to being thrown about. Does any of this look to apply in your situation?

Clive

[Paul Barker]

whats a gimble mine is on a one dimensional roller bearing, is that what you mean?

i'm using an spu with transformers on board so i think i have enough mass, is it because i have too much perhaps? but it did it with 103 also, though that is heavy too.

Wand is probably overwhelmed by the spu anyway. Sounds good though.

But I get a lot of hissing noises some of the time if I turn it down below hissing noises I get misstracking.

It is nothing more than a pretty good diy effort with many r and d issues yet to be resolved. But I'm not complaining because you have to get up at the end of the record anyway, and it sounds better than anything else I've owned. (If you can put the occasional impromptu hissing out of your mind.

[Clive]

yes, roller bearing would have been more accurate than gimbal.

The arm I have is very well behaved now it's setup well. But...I would say that anyone who wants an arm to simply fit and forget, well that isn't the case. Most of us are here because we like tinkering so it's fine for most of us and it does sound great!

[richardcooper2k]

mine is the two output pump so i suspect you have a superior valve to mine clive ! it seems to do it when the air only has a small gap to get through i.e. when the valve is nearly closed. turning down the pump setting has solved this

paul - i get the bounce back at the end of some records too. the evo arm seems to be more suseptable generally to tracking problems than the origin live silver i was using before, but most of the time my listening experience is very nice !

has anyone consulted vic about bounce back ?

[Clive]

mine is the two output pump so i suspect you have a superior valve to mine clive ! it seems to do it when the air only has a small gap to get through i.e. when the valve is nearly closed. turning down the pump setting has solved this

I must have been lucky with my valve though I must say it's very cheap and nasty but it does the job!

has anyone consulted vic about bounce back ?

I'll drop Vic an email.

[Clive]

Here's the gist of what Vic's said:

One solution is to stop the stylus reaching the label (assuming it's hitting the label area), this can be done by positioning the arm so there isn't enough travel to reach the label. A quick way to achieve this is to put come blutack on the carrier to limit travel.

The real issue could be that for the arm to bounce-back, it may be wanting to return to the beginning of the record. Is the carrier level? Does the slider remain stationary with the air blowing and the arm removed?

I find that I need to re-level my deck every couple of weeks, maybe temperature changes setup.

[Paul Barker]

Here's the gist of what Vic's said:

One solution is to stop the stylus reaching the label (assuming it's hitting the label area), this can be done by positioning the arm so there isn't enough travel to reach the label. A quick way to achieve this is to put come blutack on the carrier to limit travel.

The real issue could be that for the arm to bounce-back, it may be wanting to return to the beginning of the record. Is the carrier level? Does the slider remain stationary with the air blowing and the arm removed?

I find that I need to re-level my deck every couple of weeks, maybe temperature changes setup.

if you stop it early it bounces back off the stop.

Yes the arm is level, what do I look that stupid?
Anyway I did consult him, he didn't solve it so I live with it, but it has to be said.

[Clive]

Yes the arm is level, what do I look that stupid?

Tempting..... I just needed to add that for completeness.

I do think that this type of arm will always require some deck-specific tuning and tweaking. Trying to make such an arm work totally generically would be a real pain resulting in monsters such as the Clearaudio arms.

[Darren]

And who knows if they are without fault? have you tried one Clive?

[Clive]

And who knows if they are without fault? have you tried one Clive?

Good point Darren....no, I've not tried one.

[Paul Barker]

Sorry I wasn't intending this to be an issue I only mentioned it because Clive ran a thread on it. Vic has emailed me a suggestion but as I said to him I am not set up presently. There isn't much point discussing it theoretically, it's a non issue for me anyway. I have a lot more serious things to attend to.

[Deco-Doctor]

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[Deco-Doctor]

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