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Lyra Kleos: tracking force/VTA/azimuth questions

I just bought a Lyra Kleos and I'm mounting it on a VPI JMW 12.7 (HRX turntable). I've done a bit of research, including Jonathan Carr's many posts here), so I know VTF is critical. I've done a trial set up to Lyra specs, and it doesn't sound right - piano in particular is distorted as if the cartridge is approaching break-up. I suspect the way I've set VTF. VPI recommends measuring VTF at the level of the record, which is impossible with the electronic scale I currently use - I simply put it on the platter and took readings, after first calibrating the scale, of course, and left it at 1.75 g. VPI says that simply measuring tracking force that way will under-represent actual VTF at the level of the record by a substantial amount because of the height of the gauge over the platter. Could that be the source of the problem I'm hearing? With other carts, I've done a couple of tests that seem to verify VPI's advice, so I plan to carefully measure the plinth to platter-top height, remove the platter, and build a temporary platform lower by exactly the thickness of the scale's pan. I'll put the scale on that, and then set VTF to Lyra's specs. This will result in VTF at the level of the record measuring correctly, when I put the scale on the mock-up platter, but NOT when I just slap the scale on the platter - it will measure higher. So my question is: does anyone see any potential problems flowing from my use of this process? I plan first to set VTA slightly tail high to approximate the magic 92 degrees SRA that seems to be the consensus of opinion these days.

Also, I'd like a bit of advice on using a fozgometer to measure azimuth. In my trial set up, I've never been able to get exactly the same readings left vs. right channel with the Foz; the best is a two-division difference, right higher in level than the left. I also get a one division reading, rather than zero, on the channel balance test, with both channel lights very faintly lit. Could this be a function of insufficient tracking force, or is there something else at play?

Thanks to any and all who might feel the spirit to respond (hopefully including you, Mr. Carr).
zachteich
moonglum
619 posts
 
Please keep an open mind on VTA Zach...
The "magic 92 degrees" may not be obtainable from a positive VTA? Many samples of cartridge (not just Lyras) require a distinct "tail down" attitude. If I'm quoting JC correctly from the most recent 92d inspired discussions, Ogura only manufacture to a tolerance of +/-2 degrees. This suggests wide possible variation in the final VTA but in practice the cart's optimum may not be very far away from horizontal? (My Delos is within -0.5mm of neutral VTA depending on ambient temperature i.e. "tail down")

You will undoubtedly hear many recommendations that listening is the only sure way to hit the target, and this is the best advice.
Once you divine those settings I'm certain it will prove to be the cartridge you hoped it would be.
Best regards and good luck...
dinster
76 posts
 
Zachteich, I have been obsessing over the same issues, and have resorted to taking photomicrographs of the needle on the record and analysing angles, and have managed to get advice from several analogue guru's, for which I am extremely grateful. By the way I have a Delos and an Atlas, unfortunately not the Kleos
My summary is 1. It's all too hard!
2. These cartridges need precise tracking force, just adjusting VTA or adding a platter mat changes the sound a lot by altering tracking force, need to reset after each adjustment.
3. Both are a little better with the arm tail down, less surface noise, less edge, better balance to the sound. (and what a sound!) From my photographs to achieve a SRA of 92 degrees, I would need the arm lowered from parallel by about 15mm!!, so I think my photos are wrong, or I have one at the limit of the manufacturing tolerance. Listening gives me the setting of about 2-3 mm tail down.(11" arm)
4. Anti skate... I listened to people saying it's not important until the second last Cannon on the 1812 sent my cartridge skating across the record, now I believe it needs to be set correctly!!

In the end it's all fun, and I suspect everyone will advise you to listen and make adjustments until it sounds right to you. I think that's where I'm up to now... but what a journey, who knows what I might believe next week!
pojuojuo
92 posts
 
Forgot about VTA infirmation readed. VTA is not critical in this kind of distortions, bias adjust or azimuth adjust have, at this time, more relevance.

Put the VTF at the maximum value permitted by Lyra and with Hifinews test lp or adjust + Lp try to get the same distortion from both channels. Once you get it you have the bias right.
Fozgometer is a good component to get the azimuth properly but all the Lyras I have seen usually has this value right with a proper VTA. If you start to play with strange VTA parameters lookin for the perfect SRA maybe you will brake your cartridge.

If the problem persist you should contact Jonathan
stops
56 posts
 
If you believe the 92 degree angle for VTA as pushed by the audio press. I have a very simple way to get you close to this angle.
I use a ruled 3 by 5 index card.

Set the anti skating to zero and get out an old LP.

PLace the stylus carefully on the STATIONARY record away from any raised record edge. Place the card with the lines parallel to the tone arm on the spindle side and mark the position of the tonearm so you can see the mark when you look at the card from the non spindle side'

Remove the card.
Draw a horizontal line where you marked the card (the lines on the card help). Make this line a convenient length say 4 inches. Now at the end of the line (closest to the arm pivot) draw a vertical line of 0.1397 inches (for a 4 inch line). Draw a second line from the starting point of the 4 inch line to the top of the 0.1397 inch line.( 0.1397 is 2.23/16 inches)

This new line is exactly 2 degrees to the horizontal one. Place the card back on the record and adjust the back of the arm till you can see that the arm and new line are parallel.

Hope this helps

You can do small adjustments on the arm height by ear but this will bring you very close
sarcher30
596 posts
 
Stops, It's 92 degrees for SRA not VTA. SRA (stylus rake angle) is what needs to be adjusted for. Your method is not going to work for SRA because styli are not all mounted exactly the same angle on all cantilevers. Another variable is the suspension will sag a different amount between samples as well.
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