Fozgometer: 3 Test LP's and 3 Different Results....Now What?

[mtemur]

I have the v2 version of the Foz but in no way I'm able to get the L-R azimuth reading closer than L15-R21 between the channels on my VdH Gold Frog. The balance test is good at just a fraciton of a millimeter above 0 on the meter.
Strangely enough, the foz gave the best reading when the whole assembly (Graham Supreme II) was visibly out of balance...the cartridge is mounted using the Graham adjustment tool so I don't expect any issues there.

I still have to try a different test record and the included mains power supply for the Foz but so far I remain sceptical of this gizmo. My first suspicion was the anti-skating as VdH profile styli call for a very, very low a-s of just 0.3-0.5g, which makes the arm pull inwards on a blank record so I tried increasing it up to the point of the stylus staying still on a blank record (not recommended?) but it didn't change the readings on the Foz one bit.

Graham adjustment tool for P2S distance and overhang is very coarse but do the job. On the other hand I have seen discrepancies on the levels between headshell and top of the bearing unit. When the headshell is parallel to record surface, bearing (main) unit looks tilted to one side, not on the same horizontal plane. I think it’s because of removable arm wand. The last one I saw with this problem was mounted on AF1P turntable in Munich 2022. Anyway there shouldn’t be a problem on a high priced arm like Graham but there is.

Fozgometer is not the most reliable gadget. IMHO it tries to compensate misalignments on overhang, SRA, zenith etc with azimuth. More importantly, records are not flat even they look so. IME it’s hard to get accurate azimuth reading without vacuum hold down. There is also the high possibility of cartridge’s coils being misaligned.

I strongly recommend using fozgometer with utmost care and trying to achieve maximum numbers on both channels instead of equalizing.

 

[martin778]

Regarding the headshell not being exactly level with the bearing - that's correct, it's always a bit off on this arm. Graham has a small level next to the pivot for the VTA but it varies from record to record, indeed.

VdH carts are handmade so probably not the best candidate for testing such a tool as Foz. I have a different table with an AT33 and DV505 that I still have to test with the Foz, if it's showing the same/similar reading as the Graham, I'll be returning the Foz.

 

[martin778]

So as it turned out, the cartridge was defective and was impossible to align. The AT33 could be perfectly L-R matched on the Graham with the Foz.

 

[gwernaffield]

i have the foz V2 it is a pile of rubbish , impossible to calibrate , i ended up with the right channel lit up with out any signal going to it , even following the instructions and the new version still end up back at the same point , DONT BUY ONE , i have the original Fozgometer and have no problems with that , contacted the supplier but get told it only had a 30 day rtb , although bought new, not happy at all ,

 

[martin778]

I got the cart back but same issue - impossible to align with the foz.

 

[gwernaffield]

honest in the uk it cost £450 , i might as well off purchased a bag of bolts, the FOZ 2 is a total wast of money i feel as though i have been ripped of , if it was calibrated in the factory like they say it was , why did they not seal the small trimmers with wax so they dont move, the foz one is a better device for me , but the FOZ 2 is a waste of money

 

[Zeotrope]

i just used a foz , i down loaded the test files and put them onto a mp3 /mp4 player , and used that to test it , i did use a burned test disk but kept getting different readings, as the mp3 /mp4 had the raw files it worked better , there mut be a fault in the burning software of the cd player , so the foz is now set to one file and then test the azimuth with the test lp ,

The problem with the Foz is it needs calibration. How do you calibrate if the calibration tool is not calibrated?
No PC or CD player or preamp will be perfectly balanced if the sound output is off by ~0.5dB, that’s a big change in Azimuth.

 

[gwernaffield]

if you switch the foz 2 on it lights up like a Christmas tree, try it on the test lp and it does the same when changing track, i have tried to calibrate this using the tones off the web site through a mp3 player , but no matter what i try i just cannot get the led lights to stay off when no signal is passed through it , if the cable is not connected it lights up as well , left in the box as a big mistake