DIY linear tonearm

Hey Bill thanks for yor post and your efforts too. Wondering if you ever did a direct comparrison of a ZLM and an XLM or the XLM and the XLM ll/ I had the XLM for a long time Still have it packed away but it needs a stylus. tried a ZLM for a short while on a different table and arm thought it was ok but was not able to compare it to my XLM. I always likes the XLM and so I kept it after the tip was damaged and just never got it replaced for one reason or another. Good cartridge. Best regards Moray James.

Hi Moray, Didn't know one ADC from another until I found 2 XLMs in a box of cartridge stuff I inherited. Had the box and contents for a couple of years and no need for any of it till about 6 months ago I wanted something to try in place of an OM that was in bad need of a stylus. Didn't like the cheap Swiss one at all, and couldn't find a Jico anywhere so I bought a $13 XLM stylus from Amazon. BINGO! Pretty sure it is a Jico, and I just bought a spare. One of the XLMs was silver color and had the coils with the ~350 ohm dcr. The other is gold cased and about 800 ohms dcr. Listened to both on my LT arm and find the older silver case to be a little nicer. That is 5 stars against 4. There are lots of raves on some of the other vinyl forums. So who needs a MC cart? Glad the LT arm can handle it.
Thanks for your interest and comments too.
Rgds,
BillG
 
I have a ADC silver color the original stylus dark green also the suspension of the cartridge.
I can't find any info on the net, each side measure 355 Ohms.
The stylus marked gold color but ML X-II not XLM. I have to do some listening compare with Sure 15V type III and IV and one of my favorite cartridge from Pickering XV15.
Any idea about that ADC cartridge. The stylus look great under 20X magnifier so I'm not sure it would be worth to invest into a XLM stylus just to test it.
Sorry a bit of the topic, may be I can get some info here.
Greetings Gabor
 
I have a ADC silver color the original stylus dark green also the suspension of the cartridge.
I can't find any info on the net, each side measure 355 Ohms.
The stylus marked gold color but ML X-II not XLM. I have to do some listening compare with Sure 15V type III and IV and one of my favorite cartridge from Pickering XV15.
Any idea about that ADC cartridge. The stylus look great under 20X magnifier so I'm not sure it would be worth to invest into a XLM stylus just to test it.
Sorry a bit of the topic, may be I can get some info here.
Greetings Gabor

H i Gabor,

Sounds like your silver cartridge is the same one I'm using. I feel it is definitely worth getting the Russell Industries PM2237DE stylus from Amazon.com. It appears to be a JICO (Japan) stylus. At $13 (US) you can't go wrong even for evaluation purposes only. I don't know how good NOS ADC styli will be after all these years if you can even find one and I think they are dear.

For more information google VinylEngine or ADC XLM cartridges, or Peter Pritchard ADC. There is quite a bit written up. You may have to gather info from several sources.

The following is a quote from VinylEngine:
"There are probably only three or four phono cartridges that legitimately rank in the pantheon of all time super cartridges. Of these, the ADC XLM must be included, as many people consider it something of a reference standard."

I can't comment on your xlm vs mxl ll designation. Something got mixed up somewhere. Let us know what you do with the cartridge please and good listening.

BillG
 
One thing noted here, while the two tube has a better vertical pivot I have had to add means of inhibiting it somewhat through a low slung counterweight and more mass since it as is doesnt seem to be superior in the lower bass as the single tube. The friction of the single tube seemed to track better in the vertical plane, whilst the two tube has better lateral movement with higher mass. Here is my result, note the modified counterweight to add better stability, when the arm hits a warp the vtf increases slightly to help damp vertical movement and keep a firm footing in the groove and now brings bass performance back to the single tube performance.



Colin
 

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One thing noted here, while the two tube has a better vertical pivot I have had to add means of inhibiting it somewhat through a low slung counterweight and more mass since it as is doesnt seem to be superior in the lower bass as the single tube. The friction of the single tube seemed to track better in the vertical plane, whilst the two tube has better lateral movement with higher mass. Here is my result, note the modified counterweight to add better stability, when the arm hits a warp the vtf increases slightly to help damp vertical movement and keep a firm footing in the groove and now brings bass performance back to the single tube performance.
Colin

Colin, As I said before I thought the 14.5 grams total weight was a bit too light. So after your comments above I just added 3 grams on the headshell and 3 grams on the counterweight and rebalanced for the same tracking force as before. Yes, the bass does sound more like what I remember on the single tube setup and the first lashup of the 2 tube version. More to follow after evaluating for a while. About how much extra did you add? It seems to be zeroing in on 20 to 25 grams for the total carriage weight. You wrote "---- keep a firm footing in the groove ". My thoughts have also been about keeping the bearings firmly planted on the tubes.

Rgds,
BillG
 
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Hi Bill,

Good point on the bearing seating. I added about 2-3grams on the headshell with a small alu block and and larger counterweight. I made the counterweight as an upside down V to add further stability which moves some mass lower and outward. It's looking like 25 grams plus before cartridge is the ideal, any lower than this and the focus and weight of the music suffers, we are on the same page and its nice to know that it's not just a placebo effect :).



Colin
 
Colin, Bill,

Along the same lines... When I first tried out the single tube version, it was with an old high compliance Shure M91ed. The bass was incredible. Sort of a sub sonic feel to it. I never measured the resonance, but I'll bet it was much lower than advised.
Then I tried an AudioTechnics AT71e which I believe is very low in compliance. Bass was still good, but not like the Shure.
Now I have the mid compliance AT120et on there. Better bass than the AT71e.
My arm is 19.4 grams without the cartridge. Will try more weight like you guys.

So, I take it you both still like the double tube version better - right?

Hugh
 
Hjam,


I like the lateral movement better with the two tube, its smoother. I don't like the vertical freedom as stock, its needs to be played with by moving the counterweight center of gravity low as possible. The single tube, even though some have an issue with setting the static vtf, is far superior in its ability to ride a warp and damp its own self righting. So out of the two I decided to take the better lateral movement and work around fixing the vertical aspect. The result is having to come up with the low slung weight whereas when the stylus rides the warp upwards vtf increases which helps on the downslope of the warp and damping any possible "bounce" after it settles post warp. This helps substantially on the impact of dynamic swings.


Colin
 
? For Bill, how did that L work out for you?. Implemented as I have has surprisingly killed any low frequency resonance duration, and its easier to build. I'm glad to have the oomph back that I had with the single tube and four bearing. It's easy to get the highs they are boosted +20db, but we must remember that around 20hz is -20db approx. this means its imperative that care is taken in low response retrieval "stability"before we boost it by another 40+ db. Once you factor the math in its obvious how sensitive vinyl playback is.



Colin
 
? For Bill, how did that L work out for you?. Implemented as I have has surprisingly killed any low frequency resonance duration, and its easier to build. I'm glad to have the oomph back that I had with the single tube and four bearing. It's easy to get the highs they are boosted +20db, but we must remember that around 20hz is -20db approx. this means its imperative that care is taken in low response retrieval "stability"before we boost it by another 40+ db. Once you factor the math in its obvious how sensitive vinyl playback is.
Colin

! answer, for Colin
In a nutshell, fine. First off I didn't have any aluminum angle and the smallest at the hardware stoar was 4 foot lengths for $25 which I was not about to spend. I did find an old aluminum door bottom with the slide in vinyl seal. That was a shaped L with one side thinner aluminum flat and the other side thicker with a bunch of channels in the extrusion. It measured about 2" on both sides and with some hacksawing and filing came down to 1*. It is very ridged but can be twisted lengthwise. Mounted to the track mounting block it becomes quite firm longitudinally as well but not quite up to alum angle. So I used it anyway just for test. Cut to length and suspended it rings quite well. The extruded L should do that also Mounted to the block it still rings but at a lower frequency and amplitude. The channels proved to be ideal to set the tubes in with your 5 spots of glue. Testing it for ringing again, showed that the tubes were damping out a great deal of the low frequency ring and what was left was of very short duration. So I bought that for now. I drilled the block for the vertical mount rod and the arm lift and put the whole thing on the TT. Don't have a dust cover mounted yet and I'm interested in seeing if it will do some more killing of the resonance. Meantime I'm quite pleased with the results. Just got called for tea, gotta go.
BillG
 
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