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

301, 401, plinths and assorted idler stuff
Clive
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#16

Post by Clive »

Hi Darren,

Certainly a 2nd tank would be easy to try, sort of a 2nd set of filter caps.

However...I'm not at all convinced that any pulsing is coming from the smoothing tank. I believe it's simply down to more air coming out of the arm than can escape between arm and carrier. So the air builds up under the carrier until it pushes the carrier higher, lets the air out and then the carrier drops back down again. The solution is to reduce the amount of air.

The sensitivity of setting is another matter (I'm guessing) probably along the lines of what Nick said.

Anyway all is working fine now and I'm in Madrid so I can't experiment but I do know a couple of record shops near Plaza Mayor. I'm off there now.

Cheers,

Clive
Darren
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#17

Post by Darren »

Huh, some people.....you can go off peeps ya kno..!!!

Madrid indeed, you say it like you've popped out for a pint of milk.... :mrgreen:
Clive
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Location: Cheshire, England

#18

Post by Clive »

Hi Darren,

It's strange really, I know some cities in Europe, US and Japan better than UK cities. Sometimes it's like leading a dual life. It's really not that glam, mostly I arrive at an airport, stay in a hotel that could be anywhere (Hilton or Marriott) and work in an office. Sometimes though I make a bid for some freedom.

The record shops here have the best selection of anywhere but the quality is very variable. Buying records here that are rare in the UK and selling on ebay for the UK market could work out. Easyjet from Liverpool, you could do it!

Cheers,

Clive
richardcooper2k
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#19

Post by richardcooper2k »

the jist i am getting is that the problem clive is experiencing isn't due to the pressure varying in the air supply to the arm. it is caused because if too much air is coming through, then instead floating smoothly just above the groove, the carrier is wobbling about because the air cushion is thicker so the structure is less stable
Clive
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#20

Post by Clive »

That's what I was trying to say. Well said that man!
richardcooper2k
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#21

Post by richardcooper2k »

i also have one of vics arms although i am using it with a 401.

i also have put the pump in another room as i didn't manage to reduce the noise it was making enough by putting it in a box with rockwool stuffing. although i have the pump with two outputs which may be noisier ?

the smoothing tank (plastic petrol can) is in the same room as my hifi due to tube length. it also gives off some of the low pitched 'thrum' of the pump. what concerns me more is the higher pitched ringing it gives off (the smoothing tank) . when i put my hands on it to damp it the ringing is reduced but not stopped completly. i put a cushion on it but it is still noticable.

prehaps the 4 output pump would give reduced resonance. wether this is effecting the arm i don't know but even if it doesn't i'd like it and the pump to be quieter

i was wondering if anyone has similar experience and/or a solution.

thanks, richard
Clive
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Location: Cheshire, England

#22

Post by Clive »

Hi Richard, I don't have a solution, all I can comment is that my pump is also the 2 output type, maybe you could try a 4 output but put the smoothing tank next to the pump? It could be that the extra power of the 4 output pump would cope with this.

Do you have the pump set to max and use an aquarium type valve to throttle back the air close to the arm? This is a very recent change which has been a revelation for ease of setup.
richardcooper2k
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#23

Post by richardcooper2k »

i havn't tryed adding a valve near the arm, but my concern is more with the ringing noise coming from the tank rather than setup ease. do you think it would help with this ? not convinced i want to take the air cylinder route. prehaps i need a pump with schottky characteristics. surely if these are for people with aquariums in their houses they'd want quiet ones.
Clive
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Location: Cheshire, England

#24

Post by Clive »

How about a mains lead with a plug with gold plated connections and fuse for the pump? :-)

I don't know how to stop the noise from the tank but what I'm wondering is whether you could move the tank to the other room where the pump currently is? Using a valve close to the arm allows you to use the pump on max which pressurizes the tank better so it may be able to drive the long pipe length to your arm.
richardcooper2k
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#25

Post by richardcooper2k »

yes i should move the tank, but......

a) the noise from the pump and tank are intrusive to people in the room they are in ( and i have to at least pretend to take people other than myself into account just cos it makes my life easyier )

b) i don't know if it is, but some air vibraion may be reaching the arm and effecting the sound. i would like to rule this out
Clive
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#26

Post by Clive »

a) is tricky, there is noise from the pump and it's hard to disguise, I too wasn't happy that I could mute it in a box, if I could do that I suspect it would overheat or end up running in a vacuum. Any good at cutting a hole in your ceiling and re-plastering?

b) I wouldn't have thought this is an issue but I don't know your setup
richardcooper2k
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#27

Post by richardcooper2k »

i put my ear to the tube before and after the smoothing tank
-before the noise was easily audible
-after it was silent
so my concerns over vibration reaching the arm are releived

i looked at the pump and noticed the noise all comes from the air intake hole so i decided i needed to put a filter in it. this took the form of making sure the rock wool in the box the pump is in is up against the hole. whilst ensuring sufficient air flow to stop the stylus tracking. this has made things quite a bit quieter. hope the pump can take the strain but not sure its any worse than putting a valve at the tone arm end ?
Clive
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Location: Cheshire, England

#28

Post by Clive »

I'm told that these pumps expect to see a highish pressure at the output side so a valve on that side should be ok. If you are slightly blocking the intake I don't know what effect this has, if any.

It would be interesting if you would try the valve on the arm end. They are just a couple of quid, indeed I have a spare I could send you - there were 2 in the pack I bought. It won't quieten anything, just the reverse with the pump on max....
richardcooper2k
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#29

Post by richardcooper2k »

i have an aquarium supply place just up the road so i should be easily able to get one from there and have a chat about all things pump at the same time.
i guess i wouldn't have to turn the pump all the way up to max, just enough to give me some suplus pressure to play with and so not increse noise too much.
eventually i plan to put the pump in the cubby hole under the stairs (hoping it doesn't act as a resonant box) and drill a hole in the wall for the pipe. so the pump won't have a 'presence' in one of our rooms
richardcooper2k
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#30

Post by richardcooper2k »

pump now in cubby hole under stairs - much better
got a valve and installed it just by the arm but found with the pump turned up the noise of air rushing through the valve was quite noisy. turned pump down so it runs with the valve more open and less constricted and this has got rid of the noise
i have found having some pressure adjustment at the arm useful as when i play some (worn?) records they are more sensitive to mis tracking so then i need to increase the pressure slightly (maybe i'm running it on the low side)
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