Zaikes, I'm not familiar with the design of your arm, but wouldn't weighting one side significantly more than the other torque the bearings and potentially cause uneven wear?
Tom, I received the HiFi yesterday, thanks for the quick shipment. One question about installation: how far onto the axle nuts should they go? OOTB they cover about half the nut. Should I ream them out so they slip on further? I assume they should NOT go on so far as to touch the bearing surfaces, right?
Doug |
Thanks Tom,
Our first couple of days with the HiFi Mod have been positive and informative. Bass is much tighter. It is considerably more impactful at the front of the note, with less overhang or bloat on the trailing end. Cello and string bass lines are much clearer and more tuneful. Heavily scored orchestral passages are more transparent, more individual instruments and less mishmash. Quite good results.
The bass is sometimes almost too impactful, we literally feel airwaves. That's great when it's a bass drum or cathedral organ, but should I feel this from the mechanical action of a harpsichord? I'm not kidding, we do. Have you ever been thumped in the chest by a harpsichord note?
It's not just about the bass. All notes are affected in the exact same way: there's more impact and body at the front and middle of the note and less overhang. In our system this change is audible even for VERY high notes like cymbals, triangles, harpshichord, etc. For harpsichord this is not so good, it reduces the last bit of bloom and color.
We're going to play with VTF and try different mounting schemes before gluing the weights on. I'd like to retain most of the bass-mids benefits while allowing the extreme HF's to stay a little more relaxed. It's possible keeping the weights from damping the bearings may do the trick, so I may try mounting them on a bar straddling the bearing yoke. YMMV of course, stay tuned. |
Followup review of our HiFi Mod:
I'm a bit embarrassed. After two more listening sessions, it appears the odd effects I reported above are entirely due to problems with individual recordings. Like any high end component, TWL's mod reveals more clearly what's on a record. On good recordings the effects are good, while the flaws of poor recordings are more easily heard.
In the 'Case of the Dark and Thumping Harpsichord', it seems this recording was made in a cathedral basement, in a small room with stone walls, floor and ceiling. To tone things down they covered every surface with blankets. This over-damped the HF's but was insufficient to control echoes from the bass and the action, which remain heavily reverberent. Even worse, the weather during the sessions was hot, humid and heavy. A recording made in those conditions SHOULD sound dark, heavy and thumpy. The HiFi Mod helps accurately portray the unfortunate truth.
Of course on good recordings this closer adherence to the truth is brilliantly successful. The HiFi Mod is a keeper and a winner. Another A+ review! |
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Tom, I also suggested he glue them on now that he knows the benefits. Seems like all that mass above the bearing could cause problems.
Imagine people with plain RB250/300's on any old table being able to get such a huge performance boost for next to nothing. Sad if they don't give it a try. |
Colitas, look up higher on this thread for a post by Jimbo3 on 8/30/03. He found a product that might work on your arm. |
Bombaywalla, glad you finally got a chance to try them. We demoed our OL Silver both with and without the weights before glueing them on permanently. It was no contest.
You probably did the right thing using a little less weight for the Benz. Twl will have to come out with HIFI MkII for cartridge swappers. How about threaded weights that can be moved in or out for fine-tuning? The magic continues! |
Alc777, the Graham weights have two functions. The primary reason for them is control of azimuth-rocking on warps. Stabilizing lateral inertia was a secondary benefit AFAIK. On a gimballed Rega or OL Silver no azimuth control is needed, so the primary (only) effect of Twl's weights is the increase in lateral effective mass. |
"Doug Deacon's HFNRR test record measurements with the Hifi mod installed on his OL Silver yielded a near perfect 11Hz vertical, and slightly higher horizontal with a Shelter 501 Mk II on his arm (if I remember his post correctly) Both were well below normal audio range, and above rumble frequencies."
From memory:
OL Silver
HIFI Mod
Tom's suspended counterweight (described above, I think)
Shelter 901
~ 9Hz horizontal
~ 11-12Hz vertical
The suspended C/W is not quite as heavy or as close to the pivot as Tom intended. OTOH, reducing the vertical moving mass would raise the vertical resonance frequency still higher, right?
If Alex's new thoughts are correct, then it's okay or even desirable to have the lateral resonance freq lower, and reducing it even more might have a good effect. I'll have to add some bubble gum to the weights, remeasure and do some listening. Any suggestions for the best flavor? ;-)
Doug |
Zaikesman,
I remember posting somewhere (maybe on this thread but who could find it) that side weights threaded for in/out adjustability would be useful. I think the tungsten side weights on the Graham 2.2 are like that (4yanx?).
My thought was just an instinct, not as well thought out as what you and Tom are doing. I really appreciate the continuing contributions to tonearm theory engendered by this thread. Maybe I'll uprade my HIFI Mod some day, though I can't imagine how I'd get the existing weights off without wrecking the arm.
To heck with this pivoting nonsense. I want a Kuzma Air Line! I'm off to buy a lotto ticket... |
Alex,
You're right with all those ideas I think. That would make an arm very broadly compatible, especially if a couple different counterweights were also included. Then one could really tune in both vertical and lateral moving mass. Whether resonances at the threads would be a problem I don't know, but quality machining and very fine theads would help, and they'd give finer adjustability too. Maybe a Delrin female thread insert to prevent metal-to-metal contact?
Another idea I'd like to see is a VTF fine-tuning adjustment screw that threads into the back of a locked down counterweight. You could quickly add or subract a few 100ths of a gram by moving the screw in or out without having to move the C/W and remeasure. Big benefit for VTF-sensitive cartridges like Shelters. We change VTF every time the weather shifts: 1.95g in January, 1.70g now, who knows in July. The screw would be quite tiny, we do small VTF adjustments on our modded Silver with a rotating paper clip mounted on the HIFI weights.
Of course I'm never retreating from my main position: Kuzma Air Line or bust! |
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Hi Tom,
A few months back someone on VA tried to compare a 103R and a Shure V15xMR on a HIFI-modded RB250. Not surprisingly, the Shure came a poor second. I told him he'd have to remove the Mod or remove the Shure. ;-)
He apparently was under the impression his modded arm would improve the performance of any cartridge. Strange that anyone could think so after reading your first post on this thread but apparently he had missed the point, so I guess it can't hurt to reiterate.
Cheers, good to see you posting again! |
Hi guys, and sorry to Twl for the OT. I bought my RSR fully assembled from SoundFountain. I believe Rudolph's taking pre-orders for another batch.
My only niggle is that the edge was a bit rough. This doesn't affect functionality, it just doesn't look as pretty as it might. Rudolph has switched suppliers in an effort to improve this.
Joe,
My short user review is posted on the site linked by Zaikesman, scroll down to near the bottom. Short version: several worthwhile sonic positives, no sonic negatives.
I'll start a new thread (probably tomorrow) so as not to continue this hijack. I have information that will be of value to Zaikesman and perhaps of interest to others as well. |
"Just a simple use of basic materials, properly applied."
Twl comes out of hiding, and then tries to hide behind himself with a masterpiece of understatement. Nice try Tom but I'm not buying it!
In addition to a HIFI-modded OL Silver, I've heard my Shelter 901 on the following arms:
- Basis Vector ($2,895)
- Graham 2.2/IC-70 ($3,900)
- TriPlanar VII ($3,900)
- Schroeder Reference ($6,500)
These arms outplay the $900 Silver in virtually every respect, as they should. But a HIFI-modded Silver tops them all in one parameter: the speed and extent of leading edge transients. None of these kilo-buck arms holds the cartridge as steady for the initiation of a big groove modulation. Referring back to some of the early discussions above, even the unflappable TriPlanar's adjustable damping does not stabilize the arm as well as the HIFI mod for attack rise times and amplitudes.
A HIFI-modded OL or Rega may be the best arm in the world for leading edge dynamics. Just a simple use of basic materials, properly applied. :-) |
Ah, the magic of low level detail and micro-dynamic nuance. Yum. These allow the real humanity in the music to come through.
I "knew" this intellectually but had never really heard it until we got a new cartridge. Comparing the ZYX Airy to the Shelter 901 is perhaps something like comparing your amp/speakers to mine. There's little or no loss of macro-dynamics, but the Airy's ability to play down to very soft levels with subtlety and nuance really breathes life into the musicians. It's at least the equal of a Koetsu RSP in this regard, probably better, but without the syrupy warmth.
From what little I've found to read about them, all the ZYX models seem to share this trait, to varying degrees I suppose. I don't recall if you've heard one but I urge you to try. (That 501 can't last forever!)
Of course I should follow my own advice and consider changing directions with our speakers and amplifier. We're not quite ready to give up "full" frequency response though, particularly since we enjoy stuff like organ music with its low pedal notes. If you'll forgive the obscenities, would either a sub or active X-overs work in a setup like yours? |
I'm sad to have to report that we have officially moved on. The TriPlanar doesn't quite match the HIFI-modded Silver for leading edge transients, as I noted above, but it excels in all other parameters. That's what you'd expect for 4x the MSRP of course, so that isn't exactly news.
What is news, and very good news too, is that a well-respected member of our little community has bought the Silver. It should enjoy an active life in a loving and appreciative home rather than doddering off into idleness in my attic. Even better, I believe it's headed off to college! Not only is the Silver rugged enough to survive that environment, I have every confidence it will help open the ears of another generation of music lovers to the musical truths of analog playback. Party on! :-)
This was our first high end arm. Thanks to Twl we started off right, with solidly implemented analog playback at a sensible price. A modded Silver is precisely on the cusp of the price/performance curve, exactly what we were seeking, exactly what Twl described. Paired with the right cartridge it represents enormous value for the money. IME that is as true today as the day this thread began.
At least we kept pictures. We will always have fond memories of those Silver days. |
I've used the C/W Twl just described on my O/L Silver, based on his description earlier on this thead. I can confirm all the sonic changes and benefits he described. One more tip: adjust the mass of the weight so you can hang the thing as close to the pivot as practical for proper cartridge balancing and VTF. This should improve warp tracking and reduce the weight's tendency to swing.
I would not necessarily want to use a free hanging C/W on a floaty, suspended TT. On a solid, nonsuspended one it's a nice upgrade. Not as big as the HIFI Mod, like Twl said, but it really does reduce armtube resonance reflections. This results in less overhang on virtually all notes, for a cleaner and tighter presentation. Recommended if you can deal with a bit of fiddliness. The O-ring is essential, the C/W would be insufferable without it. |
mctigues,
Have you tried listening without the silicone dampening engaged? Try this without and with the HIFI Mod. That would probably be a good test of your question.
Personally, I have never liked the effect of silicone dampening (except on unipivots where the silicone sits directly around the bearing). On gimballed arms like your Silver and my TriPlanar, I much prefer the sound with no silicone in the trough at all. YMMV of course...
Doug
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IME with the HIFI mod on an OL Silver, the sonic improvements were entirely consistent with an increase in lateral moment of inertia. Bigger dynamics, stronger, tighter bass, faster transient response, etc.
I do not recall much if any improvement in areas that I'd attribute to improved resonance damping. No greatly lowered noise floor, no big reduction in overly resonant notes, etc. I DID hear those things when I adopted Twl's suspended counterweight, which pretty much entirely decouples the c/w from the arm. That's another story though, and it's not easily used.
Read through this whole thread if you dare. There's a lot of interesting material and experiences here. Taught me everything I know! Thanks again for the nth time to Twl for forging a path so many followed to better sound.
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There's a picture right on Twl's system page.
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