Tool for setting cartridge azimuth

I don't have a Fozgometer, I use a later model Fluke volt meter that will measures low AC voltage to verify both outputs of my cartridge through phono stage. And knowing that all phono stage "may" have slight difference in output voltage, I measure both channel outputs by plugging in the same phono input(in this case, the right channel). This way I get to measure the output of the cartridge equally and not having to compensate for the phono stage error. After that, I plug in both channels normally(R to R, L to L) and measure the output then adjust the gain pot on my BAT P10SE to match both channel.

My stylus under 22x magnifier looks perfectly perpendicular either on the vinyl or setup mirror.

 

I used the visual method for many years with my Well Tempered Record Player with good results. When the AP test record came out I started using the azimuth tracks and an oscilloscope. The problem with this is the traces were modulated by some low frequency noise signal and were hard to read. It worked good though.

Lately I've been running the signals from the test record into my soundcard and viewing the crosstalk on in the free version of the TrueRTA program. This works very well. I zoom in on the -30 to -40db range of the frequency response graph and set it to sum 10 samples. It's very easy to see the amplitude of the 1kHz crosstalk signal with these settings. I can balance my VDH MC1 by rotating the headshell within the play of the locating pin on my AT1005II tonearm.

 

In those posts, Mr. Ledermann says not to worry about azimuth if you stylus is conical (makes sense), but you should be concerned with eliptical. What about line-contact type stylus?

 

I’m certainly not an expert in the engineering of a cartridge, and would welcome some input here from anyone with the requisite knowledge, but looking at some of the posts there definitely seems to be a need for some hard and fast facts to support some of these definitions

I guess one point worth making is that, to some extent, surely we all dabble in making downstream adjustments to achieve the best sound upstream – or at least our own preference of sound – whether it be cable choice, loudspeaker positioning, or if we stick with cartridges, VTA is one example – even elements with mathematical 'proofs' such as cartridge offset etc have a wealth of different options (Stephenson v baerwald anyone?) In reality we would be sensible people and limit these, and so setting a cart to an extreme angle to compensate for faults later in the chain is not something we should contemplate (and not something I have seen suggested here), or using an interconnect with a resistive network – it clearly indicates an item of kit which is not performing correctly

I also think there is some misunderstanding of the Feickert, as well – I’m not defending it because I am a user, but do feel certain aspects need to be clarified:
it measures 3 aspects in terms of azimuth – L/R phase, LR/RL level and L/R mono. I ordered them that way because of the importance Feickert gives each measurement. Phase and L/R level should be close to each other, in terms of the optimum of 1 being close to the optimum of the other - but the literature clearly states that where there is a discrepancy (presumably caused by coil variation, as in the Denon specs quoted by blakep), then you should choose the best phase and live with a channel level imbalance as the lesser of 2 evils – my dynavector shows about -1.5dB level difference when phase on both channels match – therefore I ~think~ that this takes into account manufacturing variance across coil output?

This looks like it aligns with what Peter lederman says (thanks for the links) where he says that channel imbalance is one of the factors, but not the only one. FWIW on both my carts the channel imbalance typically strays by maybe -6-7dB on each side, from best to worst values as azimuth varies, but each change in azimuth shows them broadly keeping in sync with each other in terms of the relative gap between channels, while the phase varies significantly more (best shown using the sample graphs on the Feickert site http://www.adjustplus.de/index.php?lang=english) , which indicates to me that phase is showing diamond perpendicity to the groove and once you get this correct then the channel imbalance inherent within the cartridge is shown - but the range of changes in azimuth for Feickert do not seem to “swap” the channel levels – rather they just increase/decrease pretty much in line with each other, with my experience showing that the best phase roughly corresponds with the lowest averaged crosstalk

Tbh – I would be pretty suspicious of the Fozgometer if it can recommend an angle so extreme that it can cause damage – surely either the cart is not right in some way or in some cases an output level mismatch on a cart can cause it to recommend extreme angles (which I certainly would not support). Jeff- did you manage to patch it up with your girlfriend?

 

Yes, pretty much a given that you need to worry about it with a line contact. Peter Ledermann also acknowledges that his most expensive line contact is extremely sensitive to both VTA/SRA and azimuth which essentially is why I did not opt for that version when I had him retip my cartridge.

 

One of the things I've thought about was using Design of Experiments to optimize cartridge set-up using the Feickert software, since it does give you continuous data variables that can be measure to determine optimal setup, e.g. measuring channel cross-talk in dB.

The only thing that's been holding me back, besides the price, is the fact that I don't actually have a way to change the azimuth of my SME V, I can only measure it. The only way to change it is to get into shimming one side of the cart or another, and I am not sure I want to get into all of that, as it sounds pretty dang good right now.

I mentioned using this technique to Michael Fremer at his turntable/cartridge setup seminar at RMAF in 2009, and he looked at me like I was speaking Greek. Dr. Feickert understood what I was talking about, but said that you can't adjust the azimuth on an SME V, and the azimuth is close to perfect from the factory anyway, so the exercise would be pointless.

 

Would someone please explain to me how azimuth affects phase? It seems to me that the phase should be the same whether azimuth is adjusted properly or not.

Maybe I'm just thick headed today...

 

I think I need the "Greek translation" on this.

 

I'm not convinced it does myself. Alignment (offset/overhang) does since it changes the position of each side of the stylus relative to the groove. Rotating the cartridge about it's axis shouldn't change that position, though it affects the position of the stylus tip in the groove (not so much) and what you're actually measuring, the congruence between the direction the groove pushes the stylus and the magnetic generator.

This is an area where secondary effects, like a worn or dirty stylus, may introduce significant errors. The 'alignment' assumes that 'putting everything square' i.e. cartridge flat on arm/shell and arm properly parallel and flat to platter is not a guarantee that the generator is correctly aligned. An assumption that the cartridge maker isn't accurate.

Those with a JMW unipivot can have fun with this, and do. My arms don't twist, so I just watch them and chuckle..

 

Agreed.

For what it's worth, I use a volt meter (Fluke 175) at the speaker posts to measure and minimize cross talk. Works for me, plus I know I'm using a device that has been calibrated properly by a professional.

 

I really appreciate your advice and knowledge, and everyone elses too, on azimuth adjustment.

I know, azimuth something that you desire to get 'right on' adjusted, for sure. I've always been into total percision adjustment of instruments so I do know it really makes a big difference, no matter what you are adjusting.

But...If all else fails I will just do it the old fashion way with the mirrors. Maybe it's not perfect but it will just have to be satisfactory, it will be close, as in sound good, with trial and error and patients. I only have one turntable, 2 carts, and 3 headshells so for me to purchase the 'device' just wouldn't be cost effective.

Question: What is Dr. Feickert's azimuth alignment 'software' which measures azimuth adjustment via channel crosstalk? Is this a computer program for a PC or another allignment purchased device?

Good thread!

 

I have the Fozgometer and I'm impressed with it's precision and ease of use. There seems to be so much speculation on getting azimuth alignment correct, that one could go crazy. The Fozgometer worked for me and I highly recommend it. I also used the Mint LP Best Tractor and a digital VTF scale. This could be the best it gets because there is only 1 or 2 points on an LP side that can be in perfect alignment anyway. Almost the entire process of playing an LP side is an average/compromise of force and alignment. It'll NEVER be perfect, but music isn't perfect either so it's ok. Enjoy your records.

 

The Feickert software does the math on the signals for you, from audio files IIRC. It's not cheap, but several colleagues use it (it pre-dates the easier to use hardware Fozgometer).

I think they both work on crosstalk balancing, which for some reason results in better sound than straight level matching. (thinking about it, level matching will give equal output on each channel; crosstalk minimizing will maximize and balance the rejection of the unwanted channel. Not always the same thing, especially if your cartridge is not perfect. And none are.) I think concentrating on the crosstalk takes any channel mismatch out of the picture. (you can deal with that later with the balance control)

Fremer's 'Vinyl World' video shows this being done with a cheap multimeter, direct from the cartridge.

 

Completely agree....you're describing a small R&R study, actually. Spoken like a true SS BB!

 

Michael Fremer reviewed the Fozgometer in the May 2010 issue, in the November 2010 issue in his Analog Corner pages, he had another piece on it. He says.....

''While the Fozgometer ($250) and other measurement-based azimuth-setting devices and procedures—are more useful for cartridges with close channel-separation numbers, it can lead to unusual and undesirable results with cartridges with greater interchannel crosstalk disparity.
''So use such devices with care, and put the results in perspective—and put Peter Ledermann’s (Soundsmith Cartridges) response in perspective, too, since he’s a cartridge manufacturer (and a darn good one!). Still, if you pay more than $4000 for a cartridge, I think you’re entitled to a sample with a channel-separation disparity of under 10%.''

JG

 

ok Puma Cat - I'll bite!

I'll start another thread looking at using Design Of Experiment to optimise azimuth (crosstalk & phase) using Feickert tools

To clarify on the feickert tools:

I have his very nicely made overhang protractor, which is based on a measure between spindle and arm bearing centre, which effectively locks into an LP-sized disc, which can then be used to set up the arc - either stephenson or baerwald

I also use his cart alignment tools - although it does much more than that. It is based on al LP with the requisite tones, which are then fed to your computer, where his SW can be sued to determine the best cart settings for crosstalk and phase, provide resonant frequencies for arm and give very accurate speed/wow & flutter levels

I find them both a joy to use

 

Cool; see my post in your DOE thread.

 

Thanks a lot lads! Now people will leave my thread in their droves!

JG

 

JG - You clearly overestimate everyone's interest in statistical analysis - my own suspicion is that as we now have 2 threads looking at DOE people will actually start deserting the FORUM altogether.....so your thread is the least of everyones worries

 

Ah sure it was only jokin I was to be sure!

JG

 

I recently installed a Goldring 2200 on my Project Debut III, currently awaiting a new counter weight. Though could you guys fill me in on how to use the protractor tool that came with my turntable, to check azimuth?

 

bump

 

Actually, would be great if someone could fill me in on how to use the protractor to check my cartridge alignment as well.

 

Hello!
I know its been a while since you posted this, but I am looking to finer tune the Azimuth on my VPI turntable and was wondering if you could provide some additional detail on how you did this using the TrueRAT application. I am considering the Fozgometer or the Adjust+ tools, but it sounds like you were able to achieve this simply via the test LP and the TrueRTA program at a fraction of the cost?! Would love to hear more about it and thanks in advance!

Cheers,
Vin.

 

Yes it was a while back
I recommend Visual Analyzer for a freeware now. http://www.sillanumsoft.org/download.htm

You can use the scope or RTA function. Basically you zoom in on the crosstalk signal and it's pretty easy to see when the crosstalk is equal between the channels.

I've found there is more to it than just adjusting for minimum and equal crosstalk sometimes. The crosstalk is dominated by the position of the generator in relation to the cut groove but the stylus contact surfaces may not align perfectly with the generator. With extended line contact needles the diamond azimuth seems more important than the generator azimuth to me.

I've found that test record has me adjust the MC1 too much to equalize the crosstalk and the tracking ability suffers.