Help with vta

[clarkey555]

Just wondering if anybody on the aos knows how to adjust the vtf on a jvc ql y3f vintage tt. I have just acquired an Achromat 5mm and removed stock rubber mat which was 4 mm and just want to raise vtf ever so slightly to accommodate different thickness please help do I need to or would I be ok just leaving it as it is btw sounds bloody good at the moment. Any help or advice would be much appreciated. Pete

[aniki]

Hi Pete,

Do you know for sure if your tonearm allows for VTA adjustment? It's not possible on all arms.
However, all is not lost. 'Accurate' VTA is a bit of a grey area.
With the stylus placed on the outer groove of a record does the arm tube look approximately level with the surface of the record? (looking from the side)
Assuming of course that the arm is the same diameter from one end to the other!
If so and it sounds good, I would leave it be to be honest.
-
Just bear in mind that this is a bit vague. Most arm / cart combos should allow for a few degrees of VTA variation without influencing the sound.
Bear in mind even switching from a cheap flimsy 80's era thin vinyl to a 180 or 240gm record will change VTA a little with no ill effects.

[Marco]

Hi Peter,

I think you're confusing VTF with VTA (see your thread title and your subsequent text afterwards) ;) I'm not familiar with the JVC you mention, however from examining images on the 'net, such as this:


http://imagizer.imageshack.us/v2/xq90/913/G3ILQT.jpg


...I suspect that moving that little 'wheel', next to the arm base, will allow for adjustment of VTA, by subsequently raising the arm up and down.

What you're aiming for is the arm to be level with the record playing surface, so that when looking at the T/T from the side (with the arm placed on a record), the arm doesn't appear as being 'tail up' or 'tail down'. A small headshell bubble-level, placed on a flat area of the headshell, is the most accurate way of determining this.

If VTA cannot be adjusted, then you have two options:

A) Use a thicker mat (to lower the arm at the back), should that be what's required, or a thinner mat, to do the opposite.

B) Fit a spacer between the top of the cartridge and the headshell, the thickness of which will depend on whether the arm ends up more 'tail up' or 'tail down'. Use one that results in the arm being level with the record playing surface, in conjunction with your chosen mat.

Remember to readjust VTF (tracking force), once correct VTA has been achieved. Anti-skate should be set at approximately 0.5g less than the VTF, but feel free to experiment by listening to whatever achieves the best sonic results.

Hope this helps! :cool:

Marco.

[Nigel]

Should one be looking at the arm tube for level? Wouldn't the cartridge be a better guideline? The bottom of the cartridge should be parallel to the LP as it is playing.

[Marco]

Yes, that's why a headshell bubble-level is the best tool for the job. However, it's usually easier to see, by eye, whether the arm itself is level or not with the record playing surface. When it's out, it's pretty obvious! :)

Marco.

[clarkey555]

Thanks guys for the advice sorry Marco I stand corrected I did indeed mean vta in my thread. Me thinks I will leave all adjustment well alone as the tonearm does indeed look level and I will purchase a bubble level to check level. Just another quickie the needle hits the vinyl a lot quicker ie as soon as the arm moves from the rest over to the vinyl and lowers onto the record it almost immediately plays music unlike when I had the stock rubber mat in place it would find the intro groove on the record and maybe 2 seconds later the music would play a bit like wiping its feet first before the music played is what I now experience just down to using different thickness mats.Also Marco that wheel in the photo is the anti-skate so would just rather leave that as I would probably bollox something up forget what I just said dohhhhh!!!! I think you mean the smaller wheel near the counter weight gotcha no worries.

[Marco]

Also Marco that wheel in the photo is the anti-skate so would just rather leave that as I would probably bollox something up forget what I just said dohhhhh!!!! I think you mean the smaller wheel near the counter weight gotcha no worries.

Precisely. Try adjusting that and see what happens :)

However, if it sounds good 'as is', then there may be no need. Regarding the other issue, you may find that the T/T was set-up by the manufacturer to be used with the stock mat. In that respect, there may be some sort of sensor in place, which allows the arm mechanism to 'know' where the start of the record is.

Marco.

[misterdog]

Don't forget when using a level bubble on the headshell, to compensate for the weight of the level....

[daytona600]

3mm achromat best to replace a felt mat the 5mm sounds slightly better but extra thickness really suited to arms with adjustable height/spacers

[PaulStewart]

Hi Peter

The QLY 3F was one of the last products I was involved with at JVC. It's a really nice deck and sounds great with a JVC X-2. Marco is right the knob at the side of the tone arm pivot is the arm height/VTA lock. To be honest the stock mat was pretty rubbish, we used to run them with a suede mat when demo-ing, it gave the sound more pace. My gut feeling is the Achro Mat will be OK but one of the Loricraft type two piece cork/TICO mats would be better.

[clarkey555]

Just like to thank everyone who has given me help/advice regarding the vta. I have indeed adjusted the vta and a big thank you to Marco for supplying photo(big help bud) and Paul for advice on how to operate the locking mechanism. I am really enjoying the achromat superb little upgrade and Marco thanks again for the heads up mate regarding the vtf after adjusting vta the cart was out by nearly half a gramme. Chilling with some Hugh masekela Thanks again. Pete

[Marco]

No worries, Pete. That's what the AoS community is all about: helping each other. Glad it worked, so enjoy the choons, bro! :cool:

Marco.