Tool for setting cartridge azimuth

I just came across this tool for setting cartridge azimuth, has anybody bought one or even tried one?

http://store.acousticsounds.com/d/6...er_Azimuth_Range_Meter-Turntable_Set_Up_Tools

JG

 

Yes, I have one that I have shared with friends. This, along with the recommended Analogue Productions test record, makes setting azimuth a breeze. Putting the battery into the unit is, by far the hardest step in the process (the tolerances on the casework are quite tight). After that, it took me all of five minutes to set azimuth according to the instruction.

I can't objectively say it set the azimuth correctly (who knows?), but, I can say that the measurement is incredibly sensitive (very small changes are read correctly by the meter). The meter is very easy to read because, unlike doing a reading with a volt-ohm meter, the needle does not bounce around wildly (there probably is some kind of filter to knock out noise and other extraneous signal outside of the 1khz test signal frequency, and perhaps the ballistics on the meter are adjusted to read average rather than instantaneous values). I originally set my azimuth by sight, and the difference between that setting and what the meter said was correct was amazingly small (indetectible by sight).

The literature is a bit hazy, but, it appears that the meter does not merely read and compare voltage levels of the two channels (an approach that would not account for channel imbalance). Rather, the signal is converted to decibels and then the proper right minus left and left minus right calculation is done to factor out channel imbalance (this can be done using a volt-ohm meter, but it is a PIA). It is possible that the meter does some kind of phase relationship analysis, but, that is a guess on my part (Jim Fosgate, the designer, is one of the principle designers for the old SQ 4 channel stereo which relied on encoding four channels of information in two channels through encoding and detecting phase relationships).

 

Thanks for that very informative post. I did read someone's opinion on the net somewhere and they couldn't believe how much from vertical (visually) the correct azimuth was.

It is quite an expensive item for something which will only be used occasionally, so I will have to think about it.

JG

 

The Fozgometer theory is explained somewhere. Rather than matching the channels for balance, it matches the crosstalk in the 'other' channel (it's apparently easier to adjust when the signal is smaller) while normalizing the gain and this aligns the cartridge generator to the groove movement.

You're at the mercy of the cartridge designer and manufacturer as to whether that aligns with the stylus being vertical in the groove. However most are within the tolerance. The adjustments are small and repeatable and those I know like the method (and the unit if they have one)

 

I use the adjust+ system from Feickert - also gives many other nice extras on top of azimuth: http://www.adjustplus.de/index.php?lang=english

Both my recent carts - dynavector xx2 & transfiguration Orpheus - were not "flat" and needed some offset - how much sound difference did that actually make? maybe a little, but for me it's the adding up of all the small tweaks that makes it worthwhile, and it's really nice knowing that you have got things spot on

Simon

 

I have the Dynavector XX2 MII and just ordered a Fozgometer to adjust the Azimuth. I'll report back!

 

Yes, please do. I have the XX2 MkII as well. Great sounding cart, if azimuth adjustment improves it, I will be very interested. However, $250 does seem a bit steep.

 

If only there was a way to rent these tools?

 

I'll have a slightly used one for sale as soon as I get the "Cartwright" from the sound smith. Anybody that would like a deal on a Fozgometer that's been used four times, PM me. It's a great tool, but the Cartwright does everything. It's crazy money ($850) but we set up a lot of turntables, so for me it's worth the expense.

The Fozgometer does work great at it's function.

 

I also 'really do need' to adjust my azimuth for my NOS Ortofon 'M20FL Super' cart/needle. Just 'real close' is ok for me. Wish I knew someone with a meter but for the limited time I would actually use the meter, it's just not worth it for me to purchase.

* Can't you just adjust the Azimuth 'eyeballing the needle with a mirror laying flat on the TT base, with the cart needle resting on the mirror alligning the needle 90 degrees to the reflected image of the needle on the mirror, IE, the needle is straight up and down and not canted' and then after this is done just 'listening to the speakers' for the sound quality? Trial and error. I know it's not perfect but it would be ok, right?

Is there anything wrong with the above manual method? Or, besides using a meter, is there any other way of doing this more accurately manually? For me, very close would be fine, or am I missing something?

As always...Your advice is most welcolme and very much appreciated!!

Thanks!

 

On top of the mirror method there is the old fashioned way of summing both channels to mono with a test disc.

 

Your "mirror" method was the method of choice for many years for pretty much everyone until Dr. Feickert came out with his azimuth alignment software which measures azimuth adjustment via channel crosstalk, or the development of the Fozgometer. There is another way to do this if you have the Analogue Productions Ultiimate Test LP, and that is to use a dual-trace oscilloscope.

You can buy these used for about the price of a new Fosgometer, or you can buy a new one that is perfectly suitable for cartridge setup for about $300-$350. I use a B+K dual trace oscilloscope for setting up my cartridge. Tracks 2 and 3 on side one are used for azimuth adjustment. Track 2 sends a 1 KHz reference signal to the left channel only, with the right channel receiving no signal. Track 3 does the reverse (right has signal, left does not). On the 'scope you compare the signals from each channel simultaneously to one another (hence the advantage of a dual-trace 'scope).

The instructions are to "twist the cartridge so that the signals are as low as possible and very close to equal for each channel (this is for the "negative" or no signal channel for a given track).

Some arms, like SME Vs, and I believe IV.VIs, and Rega arms have no provisions for adjusting azimuth, so unless you want to get into shimming one side of the cartridge with very thin shims and do this comparison analysis each and every time, you're stuck with what you get from the factory. SMEs are well-known for having this pretty much dead-on from the factory, and my guess is the Rega arms are pretty accurate as well. though I have no personally acquired data to know...but Rega does make great arms, and I am sure the better Rega arms, like the RB-700 and RB-1000, this is simply not an area of concern, either.

 

That will work, too, and can also be done on the Ultimate Analogue Test LP and be visualized on a dual-trace 'scoope if you choose to do so.

 

I have both the Fieckert Adjust + software, and the Fozgometer, so I thought I would share my experiences with both. About six months ago, I got the Adjust+ software to do azimuth adjustment and set the speed of my VPI Aries 3 TT with AT-OC9ML/II cartridge. The adjust + works by having you take numerous measurements with your cartridge set at different measured angles, with ½ degree difference between each measurement. The software then graphs the crosstalk level and phase until you get a minimum difference for the two measurements between the two channels. Since the minimums of the phase and level are not exactly at the same point, you end up with something of a compromise between the two, though it’s very close.

This process took a long time with my table and arm, and I ended up having to set the cartridge at about a 1.25 degree angle to achieve the best results! My system sounded great, however, with a great soundstage and instrument separation.

Shortly after this, I replaced the cartridge with a Dyna 20XL II. The results were almost exactly the same, the cart had to be pretty severely twisted to about 1.5 degrees to get the optimum setting. This made me really scratch my head- is it possible that two different carts from two different manufacturers have the diamond attached at the same angle off center?
I decided to bite the bullet and purchase the Fozgometer, and see if that concurred with the Adjust + results. Now the two systems measure things slightly differently The Fozgometer measures “channel separation and channel balance,” while the Adjust + measures “level and phase angle of crosstalk.” Additionally the Adjust + measurement has to be taken post-phono stage, while the meter is sensitive enough to work right off the cart.
I was able to get perfect measurements with about half of the “twist” in the cartridge with the Fozgometer. I decided to take the measurements post-phono stage with both the Adjust + and Fozgometer. The results were pretty consistent using the two different methods, channel balance was still perfect, but crosstalk was no longer minimized.

My conclusion is that the phono stage (a BAT VK-P10) was introducing a little crosstalk to the signal that I was able to overcome with an additional twist of the cartridge. However, channel balance was still perfect. I, however, decided to use the azimuth adjustment from the Fozgometer, since that was the true azimuth of just the cartridge and, to my ears, the sound is just as good. Also, the Fozgometer was 10X easier! The Adjust +, though, is great for setting the speed and taking other measurements.

So IMHO, the Adjust + is less than ideal since you are not taking the reading direct from the cartridge. I am a little puzzled , however, that the phono stage is adding crosstalk as it is a true dual mono design. Perhaps it is just amplifying a slight amount of crosstalk present at the cartridge level? Any thought s on this would be appreciated.

 

Hi Ray,

as an adjust+ user, I am very interested in your conclusions

You seem to be saying that as your phono/pre-amp adds imbalance, you prefer the Fozgometer (crazy name!) because you can take a reading direct from the cart, and get the cart perfect, or at least within the tolerances of the arm/Fozgometer

That means that all your hard work in getting the cart correct will then be affected by the imbalances later in the chain - I know you said that you could not hear differences between the tools, but for me I would rather have a final output that measured as good as I could get it, rather than a front-end which was as good as I could get it, but knowing that the rest of the chain was adding known variations (albeit ones you cannot hear)

maybe try swapping interconnects/arm cables to see what the imbalance does, as that will help you to determine exactly where it is introduced (and will help in your conversation with the manufacturer?)

Are you also assuming that the Fozgometer is perfectly aligned? It's implied but not explicitly stated whether the measurements were the same on the Fozgometer both before and after the phono stage output, but rather that they did not match when both Fozgometer and Adjust+ were used after the phono stage. So it's quite possible the issue is with the test equipment (at least as possible that the phono stage is misaligned) so that might benefit from checking as well - maybe something like a PC induced test tone or a test CD with tones would help you check that?

It just strikes me that as someone who has 2 azimuth tools you are clearly concerned about getting it right - if those tools are indicating something is not 100% in the system, then if it was me I'd be looking to get that resolved

Puma cat - Hi - FYI, the SME' Vs are available with a removable headshell for 9" arms (I think they are mandatory for 12" IV variants) - I know 'cos I have one

 

I'm also interested in Soundsmith Cartwright myself and will preview it at CES.

 

I'm not totally clear on how either the Feikert or the Fozgometer work but it is my understanding that with the Fozgometer, at least, the device does not and cannot take into account any channel imbalances in the cartridge itself. Perhaps the Feickert does.

As most cartridges are going to have slight imbalances (many of which owners are going to be unaware of if the manufacturer has not supplied dedicated specs on the individual cartridge), in many cases owners of the Fozgometer are going to end up with unusual azimuth adjustments which, in effect, are compensating for a minor defect in the cartridge.

I'm running fully balanced from the cartridge so unable to use the Fozgometer in any event as it does not offer a balanced input. I also have individual gain pots on my phono preamp to adjust channel gain separately for left and right. Both my Denon 103R's have slight imbalances (one having an output of .31 mV on R and .32 mV on L and the other having .29 mV on R and .30 mV on left-information graciously supplied by Denon with an individualized spec chart on each cartridge) so the concern I would have using the Fozgometer is that I'd end up with a poor azimuth adjustment to compensate for the imbalance.

I've heard of users ending up with very "extreme" adjustments which are likely compensating for such deficiencies in cartridges, many of which are probably considered within "normal" specification and some which probably are not. The concern I would have is record wear or groove damage as a result of an extreme adjustment like that and, frankly, I'd rather just set it by eye (and to some extent ear) getting the stylus into the right position. I would not be comfortable with a severely (or even moderately tilted for that matter) cartridge.

As such, I'm not really sure that I'm comfortable with these devices.

Any comments from Feikert or Fozgometer users (or anyone else)?

My understanding is that the Cartright above does address this issue but I'm not fully sure of how it does it.

 

Hi

The Feickert takes the output from either phono stage or preamp tape-out, so it is effectively seeing what the power amp sees - what it cannot do is determine where in the chain the imbalance(s) are, but rather allows you to adjust the cart angle to reach the best compromise between channel balance and phase of the signal, taking into account the summed error of all the preceeding equipment - any device which claims to do anything more must connect direct to the cart, or compare against a seperate measure of the other items in the chain (pre-amps and cables) and then compensate for them to give you the "pure" cartridge readings - although, as my post above, I don't really think this is valid, as you could end up with perfect cartridge alignment which is then corrupted by other components

As an aside, I recently moved back to my Dynavector XX2 while my other cart is getting a retip, and it measured really badly in Feickert - upon the distributor examining it there were swarf deposits inside the cart which were at such a level that they were affecting performance, so it went back to Japan for a clean-up. Using the feickert (or theoretically the fozgometer) I could easily determine the fault with the cart and not elsewhere. It's now back and measures almost perfectly, in respect of Azimuth

As for the "extreme" adjustments you mention - if I got a cart and it was off by a significant amount then it would be returned, not so much for the groove wear reasons you mention (in theory what you have done is actually to align the diamond centrally, so it should actually be better in that respect) but because an extreme angle will mean other aspects are not right, such as centering the cantilever in the coils

 

I am determined to get to the bottom of this, and need to do more experimentation with all the variables involved. My reason for sticking with the Fozgometer settings until I work through the issues are that the azimuth adjustment is meant to get the cartridge aligned properly. If something is happening down the chain to throw off the crosstalk, it doesn't make sense to me to throw off the cart alignment to make up for something amiss in another component like the phono stage. I would rather address the issue at its source.

BTW, to make it clear to everyone, the measurements I took post- phono stage indicate that the signal from phono stage are channel balanced (i.e. volume is identical for both channels), but there is more crosstalk than the measurement taken pre-phono stage.

 

This is what I use. I also agree that there seem to be so many variables in the setting (slightly damaged cartridge, preamp/phono stage/amp balance, anti skate, cartridge alignment, etc) that is would be easy to over correct the azimuth for other issues. In the end I rely on an eyeball test with the mirror to determine that azimuth is not grossly over corrected with the settings from summing both channels.

 

Your understanding of the Fozgometer is incorrect- the crosstalk measurement is independent of channel imbalance. It also performs a channel balance test, and my cart was dead-on in terms of channel balance. Even if it was not, that would not impact the crosstalk measurements according to the maker. I also have balanced outputs, but used XLR-to-RCA adapters.

 

Hi Ray,

Puma Cat (who posted earlier) has started another thread on this forum which may help – it concerns using something we both utilise in our day-jobs (Design Of Experiment – a statistical tool to determine optimum settings) and how it can apply to hifi. Although his thread deals specifically with Subs and not carts, there are some aspects of preparation for Design Of Experiment which may help in finding out where your issues come from

Applied to your case, you first need to determine whether the mismatch you are seeing is actually a feature of the measuring device (Fozgometer) – if you take a few readings – say 3~5 - without altering anything, and then compare them, you will get a good indication of the accuracy/repeatability of the Fozgometer, and then you can see if the mismatch you are getting is outside the limits of the tool or not

Assuming it is, then the next action is to run the same number of repetitions as above, but on the other setting – so of the first set was from the cart, then the next is from the phono stage – the results should approximate the range you got from the first set, and also confirm that you are still getting the mismatch

Again, assuming you are, then run through all the variables within your specific setup which could affect the outcome – the cables used is an obvious one - and then work out ways of re-measuring to see which has the effect/error you are seeing. In the case of cables, simply reversing the cable will easily show any L/R bias they have

It might seem a drag to do, but it is a really good way to ensure you have considered all the factors, and if you intend to take this all the way, assuming that somewhere there is a component with an issue, then it will only help when talking to the manufacturer

 

Thanks- it sounds like it would be worth the effort.

 

No problem. I had recalled reading a post or two from Peter Ledermann at VA and could not find those. I've been able to track them down and, although I'm still not totally clear, I may have confused a channel output imbalance with what he refers to as "channel separation".

I've linked to both of those posts here:

http://db.audioasylum.com/mhtml/m.h...essage=&sort=score&sortOrder=DESC&forum=vinyl


http://db.audioasylum.com/mhtml/m.h...earch.mpl?forum=tweaks&searchtext=SST+extreme

for anyone that might have any interest.

To be honest, I am still leery, and particularly leery on the way in which the Feickert supposedly works and maybe I still don't understand. I simply do not see the point of making an azimuth adjustment at the cartridge to correct for what potentially could be imbalances in the phono stage or further upstream.

 

Someone used a Fozgometer on my girlfriend's cartridge and the angle was so severe the stylus on her Van den Hul nearly got lunched when playing. If your channel voltages are exactly right, this gizmo might work well, but if they're off (which isn't out of the question), the compensation will be so off you'll risk damaging your cantilever or stylus.