The Infinity Black Widow Tone Arm

The graphite upgrade is far stronger than the aluminum and much less prone to damage by mishandling or inappropriate contact.

The Black Widow does NOT have a unipivot! It has knife edge for the vertical and ball bearings for the horizontal movements.

 

"nothing" like is a bit extreme; I've owned both at the same time and I can assure you they are very very similar.

 

You're right about most MC carts with the BW.
How can it get any more user friendly? Even alignment is a breeze.

 

The Moving coil cartridges are usually low compliance ones and require the added weight to work well on the Black Widow. This, as I had mentioned earlier can easily be done to bring the cartridge/arm resonance into the 10Hz range. They work perfectly together when that is done correctly.

Yes, the Magnepan Uni and the Black Widow have many similarities, but fundamentally different in their pivot design as mentioned earlier. The Magnepan was one of the arms I had on my turntable for a while, but after every tonearm I keep going back to the Black Widow because it seems to help the cartridge pull a little more out of the groove, with my Shures, Denons, A-Ts, Grados, MM & MC cartridges. Adjusting, aligning, balancing and optimizing usually takes an afternoon (if all goes well) and I have to say well worth it. Records have to be properly cleaned (washed and dried) prior to playing.

 

Pi thanks so much for your input, I did not know about the evolution of the Black Widow. It appears mine is the oldest one, as it is aluminum. I was told some of the newer ones had some type of damping trough, where damping fluid was used. I was told those rarely surface. Anyway, thanks so much for the informative info on the arm!

 

I've owned a couple Black Widows, and a couple Rega variances, which I own neither now. I think the mid-centric compliance of the Rega is more sensible with modern cartridges. Just my opinion, but either would be a nice choice.

 

Yes, the damping trough was a plastic one that attached to the stand and was filled with silicone oil, and a plunger that attached to the arm. It slowed and damped the movement of the arm. This was Infinity's solution for the poor user adjustments that they had to contend with. It was only on the tapered carbon tube versions, and only some of those, not all of them. The damping trough was very cumbersome and limited the movement of the arms, to where many just removed them. Some users complained that it caused the sound-stage to drift on off-center of warped records, and when removed, the sound-stage became stable on the same records with little change in the tracking ability.

Looking at the picture posted by Wardsweb, I have never seen the black attachment with the bolt as shown in the picture in that position. It looks like the plunger of the damper, but pointed up and made ineffective. Also the arm looks like the tapered carbon version, because of the shine of the tube, and it just looks tapered which could be an optical illusion.

The aluminum version is not that shiny and has a thin step in the shaft just past where the tonearm stand holds the tonearm.

 

What parts or concepts are similar? The ADC LMF series tonearms appear to be the only tonearms that are even close to the Infinity Black Widow.
Sorry about the double knife edge bearing mistake.

 

I used the plastic weights that came with the DL103D and it still didn't track as well as a high compliance cart.

Adjusting, aligning, and balancing shouldn't take more than a half hour.
You just have to compensate for the little extra movement that occurs when tightening the main nut to the base.

I found that the Infinity alignment specs worked the best for getting near perfect alignment and sound.



This was just a temporary mounting to test for a future setup.
The damping trough is nice, but not really necessary to get great sound.

 

My Magnepan Unitrac 1 tonearm was fitted with an Accuphase AC-2 low output MC cartridge when I bought both new in 1984. They were installed on my (also new) SOTA Sapphire. I recently returned this combo to service and it works great!

 

That one looks bent to me, too.

 

Well, when all was said and done, it looks like Pi Engineer really had his facts straight. I just happened to find this bit of information, and for those that come after me and desire the Infinity Black Widow arm, they need to look for that evasive 3rd generation arm, the composite material tube that can handle a bit more mistreatment, and it was the final version of the Black Widow, a ONE piece tapered arm. Anyway, here is the information, I hope this helps someone else! Thanks to everyone that gave me their thoughts and opinions, it was certainly appreciated, and I think I made a good choice.

Here we go:

The arm. Infinity Black Widow circa early ~1980s
The Infinity Black Widow tone arm did not have an easy birth. Its earliest version was a very low mass two-section aluminum arm-tube version. It had the unfortunate tendency to break when mishandled. The later versions featured a graphite arm tube. There was a two section graphite tube, then finally a 1 piece tapered graphite tube. Later, a damping trough was available to accommodate lower compliance cartridges becoming more and more popular in the 1980s. With the high compliance cartridge I've currently mounted, there is no need for it. The trough is empty for now.
The pivot design is knife-edge vertical and ball bearings lateral. Anti-skate is magnetic and set by sliding the adjuster ring fore or aft. Vertical tracking force is set by turning the counter weight, itself on a threaded barrel, one way or the other to adjust. The counterweight is marked into .2 gram graduations as a reference. I used a digital vtf scale to set this important parameter. No need to pay attention to the graduations on the counterweight. But one could. Vertical tracking Angle is set by releasing the set screw at the base pillar and then you either raise or lower the entire arm at its mount.
The head shell does not offer slots, just round holes. In that way effective length between pivot and stylus tip is locked. To set overhang one must adjust the mounting distance at the sliding base by releasing the large threaded lock and sliding the entire arm within its mount fore or aft. There is enough room in the head shell mounting holes for adjusting offset angle (Zenith). In practice alignment is easy when done in combination with a two-point protractor or an arc protractor. The supplied specs of mounting distance, overhang and offset angle indicate an alignment design intent per Loefgren B with null points at 70.3 and 116.6mm. I was able to achieve a Baerwald (Loefgren A) alignment using an arc protractor. The null points on the Baerwald are at 66 and 120.9mm. I think I prefer this alignment over the Loefgren B, but either should suffice provided the process is carried out with accuracy.

 

That picture was actually taken before the turntable was shipped out. You have a good eye and I actually went back and looked at all the pictures BEFORE the turntable was shipped, and you know what, the arm is NOT bent, it is actually "slightly" flexing under the weight of my Shure V15 Type V-MR cartridge, I believe that is exactly what is happening. I have some other pictures where you can really see the arm, and I believe that 6.5 or so grams is creating just a very small downward flex. I can honestly say, I have never touched such a delicate, fragile arm. Obviously something has to give to achieve a 3 gram effective mass!

 

Well, there it is.

 

What you are looking at is the "step" where the tube is graduated to a thinner tube. I triple- checked the VTA before this turntable was shipped...the arm tube was straight.

 

I see. This has been a good thread. I always wanted a Black Widow. I naturally would have gone for aluminum instead of graphite, and now I know to go the other direction.

 

I think Dave is correct, at the step, and after the step, the appearance of a bend is more pronounced. I had a bit of fun with this, try expanding the photograph to full size and then carefully put a straight edge at the back of the arm right at the top, lining the straight edge perfectly with the top of the tube. As you get past the step and near the cartridge, you actually see the flex and I am confident that small amount of flex is being caused by the weight of the cartridge, and although I did not even put the platter on and test anything, I could almost guarantee you, that flex would have relaxed to some degree as soon as the stylus hit the grooves, at least 1.67 g less. I do wonder what impact that constant cartridge weight would have over years of it's weight pulling on the very thin, lightweight, long aluminum tube? There is certainly some reason the wise Infinity engineers changed from aluminum to graphite. I do agree with chadbang, if your going to do Black Widow, do a nice graphite, third generation tube that "hopefully has no memory". If Dave was able to get his arm technician to purchase a surgeon's magnifying glass headset and some tiny needle nose pliers, and he could thread those nice new Cardis wires through that long graphite arm and use the great new Cardis connection cables with POP art RCA connectors and Cardis connectors at the cartridge, what a killer updated arm that would be! I'm on board for that. I can tell you this, I NEVER noticed any bend in the arm before shipment and neither did Dave, but when I received the table, it looked like a mild horse shoe, not really, but it was much worse than the picture posted here, and Dave was on the problem so quickly, insisted I send it back to him immediately, issued a UPS return , I could not have received any better assistance from ANY large turntable manufacturer, he has been wonderful. I think everyone has learned some valuable information from this situation. For me, it was a safer bet to go with the new Rega (Moth) OEM arm with new Cardis Wiring, clips, and POP Art RCA plugs and a nice warranty. Dave not only helped me make that happen, but helped with the cost of the change as well, so can anyone do better than that, I think not. Can't wait to get the table back, thanks Dave!

 

Apologies all, I did not have ALL my facts straight! Just learned that some Black Widow tonearms had a metal trough. I imagine the first was a trial with the plastic ones, and once proven, the final version was machined aluminum I believe. The knob and black sleeve in Wardsweb's picture is the tonearm plunger attachment.

The Black Widow tonearm does not bend under the weight of any 'normal' cartridge. If there is an actual bend, it could be that the aluminum tube had been damaged, possibly bent then bent back, and the aluminum near the joint area had been compromised and weakened,. The stepped carbon version is quite a bit stronger and more rigid. Never had any of those bend unless it was damaged or being damaged, never under the weight of even a heavy and weighted cartridge.

nm-west, I always used small Stainless Steel plates as weights in the mounting of low compliance cartridges, and SS rods inside the balance tube to achieve the correct balance, also increasing the effective mass of the tonearm and getting it to work perfectly with the cartridge by lowering the natural resonance to the 10Hz range. The arm is more than stiff enough to handle the extra weights and still sound and perform as intended, which by any measure was spectacular! I have not come across a cartridge that didn't perform really well with this tonearm when installed and adjusted properly.

To my ears and in my system, the stepped Carbon version without the damping trough is the best sounding. Not sure why, but the background always sounds a little darker and all the sounds are a hint more dynamic. When balanced and weighted appropriately, this arm provides the tightest most coherent bass and the crystal highs that are not at all sibilant, even on some of those nasty 'ESS" sounds, that I have ever heard from vinyl.

It takes me the better part of an afternoon to set up the arm for a cartridge because I recheck everything at least a couple of times and I adjust all the parameters, including actual stylus angle with a digital microscope. Adjusting and checking all the angles and settings per Michael Fremer's directions has resulted in much more accurate sound from all my cartridges than any other method I have tried and the arm actually feels even more stable too.

I tried several different alignments, and I have settled on both the Infinity's suggested settings and the Loefgren A and I did notice a very slight improvement in clarity with the very high frequencies in with the Loefgren A alignment. The very deep base seemed ever so slightly more coherent as well, but impossible to do a-b comparisons as you might imagine! For the alignment info refer to this page on Vinyl Engine:

http://www.vinylengine.com/tonearm_alignment_calculator_pro.php?arm1=Black widow&l1=ps&a1lv=222&a1=cu&oh1v=15&oa1v=21.017&l2=ps&a2lv=&a2=la&oh2v=&oa2v=&arm3=Lofgren B&l3=ps&a3lv=&a3=lb&oh3v=&oa3v=&arm4=Stevenson&l4=ps&a4lv=&a4=st&oh4v=&oa4v=&og=iec1&ogv=&ig=iec&igv=&cal=y&submit=calculate

 

^^^^ Great BW post for future owners..

"I tried several different alignments, and I have settled on both the Infinity's suggested settings and the Loefgren A"

There's a lot I haven't tried with the arm yet, but the Infinity setting was the only one that looked visually perfect at both spots.
Your words have encouraged me to try heavier less compliant carts with it, thank you.

 

Thanks to all, for the history on the Infinity Black Widow tonearm, and for such an informative post for future Black Widow tonearm owners. And for those who own the arm and desire more knowledge. I learned a great deal reading this superb discussion. And threads like this one are the SH forums at their finest. Like is not strong enough, we need a Love button for this thread.

 

New forum member as of about 10 minutes ago, as this looked like a good place to get an answer to my Black Widow cartridge alignment problem. I've got a new-to-me Black Widow mounted in a Luxman PD 441 table. It came with all the original Infinity documentation. Using a Feickert protractor, I set the mounting distance at 222mm. Since there is no adjustability of the position of the cartridge in the arm, to speak of, I am having a large problem with cartridge alignment. The stylus tip falls a good 10 millimeters behind the 222mm alignment 'dot'. Moving the arm from what would be the outer groove to the inner groove, the tip tracks exactly the same 10mm or so behind the line it is supposed to be tracking on. Lofgren, Baerwald, Geodisc protractor, whatever.
It's as if the armtube itself was shortened. I've been looking at this for over an hour, thinking I must be having brain fade somehow, but I have set up a lot of cartridges on a lot of arms, just never one on an arm which didn't allow for adjustments, as far as I can recall.
Any ideas on what I am not seeing here, if anything? And if someone who has one of these, the one in question here is the carbon fiber armtube, could you measure it for me? Mine measures 197mm from the point of attachment to the 'headshell' to the point where it enters the metal near the pivot. Though, having said that, the overhang seems to be correct at around 15mm, using the Infinity cardboard jig.
FWIW, if I change the mounting distance/pivot to spindle distance to 215mm, everything aligns more or less perfectly, Lofgren, though I haven't totally dialed in zenith yet, but that's not far off.
Though that puts overhang at around 18mm.
So, to align the cartridge, I need a mounting distance of 215mm which results in an overhang of 18mm, whereas the factory jig calls for a 222mm mounting distance and a resulting 15mm of overhang.
What am I missing here? Did they make a different version with an alternate geometry?

 

If you have no ability to adjust yaw or stylus to pivot distance at the headshell, then you have to set the stylus to pivot distance by moving the arm base until the two alignment points are at tangents - BE VERY CAREFUL. My guess is that there were different length Black Widow models produced (where it seems like only one is mentioned as standard) and that you have tried to align your model to the figure given for another model.

 

John,

Thank you. That's what I ended up doing, as I could not see any other way around it. Kind of violates my sense of propriety, but I guess it forces me to widen my horizons. Having someone else validate my decision eases the pain somewhat At any rate it sounds fine. Thanks again.

 

Well, what happened. After trying my best for 6 months to find a Thorens vintage turntable and arm that worked for me, I finally gave up, it just was not meant to be I suppose. I ended up with a turntable I never expected to purchase, at least, not my first one, a VPI. I wanted the Prime, but the price was PRIME as well, and I thought a VPI Scout might be a nice starter turntable, and so I called VPI and the owner said he just finished (3) "special" Scout tables, last ones ever. He said I'm looking at them, all three have 2" acrylic platters, something they don't furnish on the Scout tables now, and since a 2" stainless is a $700 add, that was an easy decision. When I received the VPI I actually understood WHY they are so popular, the Uni-pivot arm, the easy alignment tool, the beyond incredible design, the wonderful, heavy duty motor in a rock solid housing, and set up was so easy. Coupled with the Parasouond JC-3+, I have never experienced sound like this from a record. I worked with a couple of companies to design a 1/4" full dust cover, a huge piece of granite for the base with just the right feet, wow, am I a happy camper! I wish I could post some pics of this fantastic dust cover and granite base, but I have no idea how to post a picture on this site, never could figure out how to post a picture from my computer documents in lieu of a URL??