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VTA, SRA, tracking force
Greetings,
Great article on VTA/SRA. Congratulations!
I realise it's over a year old but I'm a reformed audiophile (I am now a
music lover) and don't do so much Hi-Fi reading, or Internet surfing, any more.
I fully concur with your idea about center of gravity. I thought of this fourteen years ago while a student at Cambridge, tweaking the SME3009 SII on my Thorens TD150.
On the SME 3000 series II arms, you can rotate the counterweight on the rear arm tube to lift the outrigger weight up or down, and therefore set the vertical position of the center of gravity. Combine this with the ability to adjust the outrigger offset, and therefore set the lateral balance, and you have an arm that can be balanced to remain in any
position - there is no restoring torque when the arm is deflected.
Moving the outrigger forward on the graduated scale will then set a tracking force which will remain almost constant with vertical deflection, and without the need for perfect turntable levelling.
Get all that even approximately right, and you will find that your setup will be less sensitive to arm height (SRA/VTA) and antiskating adjustments; you will not need to micrometrically adjust these. You will also find that your cartridge will track at its best at the lowest recommended value of tracking force.
This is achieved because zeroing out centre-of-gravity related torque removes the effect of arm deflection from both lateral and horizontal tracking force.
Another myth: antiskating. The most elementary consideration of the force at work - static friction - and the geometry - 27 degrees or so of offset, plus or minus a degree or two of tracking error over one side of an LP - reveals that the skating force should be constant over a record side, as static friction is independent of linear velocity.
Measurements I made at about the same time confirmed this. The antiskating setting for simultaneous commencement of mistracking in both channels while playing a 1kHz test track remained at a constant percentage of tracking force with the stylus in the inner or outer grooves, and at both 33 1/3 and 45 RPM (the frequency changed of course, but the distortion again commenced simultaneously). Yet how many times have we heard claims that antiskating should be set up so that it
decreases towards the record centre, where linear velocity is smaller?
Static friction is also independent of contact area, yet how many times have we heard that linear-contact styli require more antiskating force?
Since experiment confirms that static friction is the primary force in play, the only variable significantly influencing antiskating force should be the offset angle and arm length. Since these are just about constant for a particular arm, the optimal antiskating force for that arm will always approximate a certain percentage of tracking force for that arm.
My experience of the SME 3009 and 3012 shows that this is always about 100% - antiskating force always about equal to tracking force.
My hi-fi friends are always stunned when I set up a cartridge in just a few minutes - for them it takes hours, or even days, of listening, tweaking, and listening again. They think that I am just sloppy and don't care about optimum performance. I acknowledge their superiority, disclaim all pretense to being a hi-fi enthusiast, put on a record and
pour them some drinks. I get no complaints about the sound, but then again my friends may just be too polite.
Best regards,
George - E-mail: george (at) karaolides.com
GH
Hi George,
Many thanks for the mail, both interesting and informative - the whole subject of arm set-up has been beset by black magic and snake oil for a long time, about time we had some serious scientific investigations, but it'd probably end up as a Phd thesis (takers anyone?). The centre-of-gravity issue is one that may possible explain the differences in set-up between arms and anti-skate is a another whole can of worms. I wonder whether the shorter wavelength of groove modulations towards the inner track may increase drag, or what happens with very heavily modulated sections compared with near silence? Do very high amplitude/rapid deflections of the stylus cause an increase in drag as the stylus mass resists changes in direction
For example does a recorded square wave (or as near as you can cut) have more drag at a given frequency than a sine wave? Will that drag be greater in the centre of the disc? But then again the groove is travelling more slowly so probably not? Here I'm merely thinking out loud and digging deep in the shallow pit of my knowledge and I'd love to have an evening with you and a piece of paper just working out the theoretical possibilities - you could have a lot of fun working it out.
All the best,
Geoff Husband
System choice under 3000$
Dear Lucio,
Hi. I am writing from India. I needed some advice - am looking at putting together my first (read 'budget') audiophile system. I have been reading up on this stuff for years - as I understand it, these are my options - solid state or tube,
cones or electrostatic or horns, pre and power or integrated, cd/sacd/dvd/vinyl.
I came across your site today for the first time - and have been reading it all day. Very nice work.
Realistically speaking - I was looking at a NAD integrated 320BEE and a Mission M71or B&W 302 bookshelf type configuration. But I don't want small, cheap and "made in China" stuff which I will outgrow.
Please bear in mind that there are very few international brands available in India - and everything is 2 to 3 times more expensive here!! There is Denon, Nakamichi, Sony, Philips, Onkyo, Yamaha, Infinity - HKardon, JBL, Bose and a few more.
So, basically I am buying blind. If I up the budget - and dream a little - I can see a
LC
Dear Adil,
it is hard to buy "blindly" without a pale idea of how a component sounds like. Anyway, there are certain components that are so "classic" that it is hard to go wrong. The Rega P2 or P3 are among these, for example. Price may vary from 500 to 700$ depending on configuration.
As for bookshelf loudspeakers the Linn Kan (or the bigger Katan) is another "evergreen". Place them against the rear wall and they'll give you years of musical satisfaction (though NOT a deep soundstage).
Another "classic" is the Sonus Faber Concertino (or Concerto), with better soundstaging ability. As for the amplifier, I'm not familiar with the Pacific Creek you mention, perhaps a Opera Consonance "tubed" integrated amplifier (we've reviewed a few of these). If bought directly in China they are EXTREMELY affordable (and have a very high VFM). Finally, you need a CD player. Plenty of choice here: see, for example, some of the entry-level players we've reviewed here on TNT-Audio (NAD C521, Cambridge Azur 640C v.2 etc.).
Hope this helped somehow,
Lucio Cadeddu
A suggestion
Dear Lucio,
Just an idea: I think it would be nice to have a sorting function for the list of equipments reviewed.
This will make it easier for me to locate those new CD-players, without going through the review article one after another.
After reading your review of the T-Amp, I bought one for my family and one for my sister's family.
We all enjoy the music much more. (Now I consider an upgrade to my CD-Player).
Thank you very much for your effort to maintain the web site.
Yours truly,
John - E-mail: johnchoy (at) esa.com.hk
LC
Dear John,
the reviews lists certainly need to be made more readable and searchable. A "Published on..." near each review of each list will help identifying the most recent ones. I hope we'll be able to do this from 2006 on.
Glad to know you've been hit by the T-Amp bug! Now you may need a T-Preamp! You may wish to know we're currently hunting for T-Transports, T-Dacs and T-Speakers, i.e. extremely affordable components with "stellar" value for money. We've already found some :-)
Stay tuned!
Lucio Cadeddu
Great RB300 rewiring article
Lucio,
I love Werner's article on rewiring the RB300. I was in exactly the same position as he was a few years ago. I had heard it was possible and wanted to do it myself. I found some silver-plated copper solid-core wire at Maplin and wired it straight through to phono plugs, with a separate earth wire. Exactly as Werner said, I spent a whole day threading my wires through the tiny hole in the arm. Because I did it at my workbench in the garage at Christmas, I ended up very cold and with a sad wife.
The improvement was worth it, however (well not the sad wife, but you understand). A much more rounded and colourful sound, though with a little built-in anti-skate :-)
Later on I rewired again with the Incognito kit. Amazing -- you can remove the arm tube! This time I did it in a couple of hours, and a lot of that was removing the old wiring and cleaning out the screw hole in the pillar where I had soldered my earthwire, so that I could fit the armbase plug. A lot of the rest of the time was plucking up the courage to cut the wires ready for soldering the tags -- you get it wrong and that's a lot of money wasted! But yes, the tags are unsurpassed.
Werner's comments on the DL103 playing music remind me that if it's music you want you really must audition a Nottingham Analogue Dais and Space arm. I used a Garrard 301 with full Martin Bastin plinth and mods for several years along with my RB300 (plus Bastin counterweight and armony base) and it was an excellent, consistent and musical deck. But the Dais really is something else (as Martin himself is the first to admit -- what a really nice hi-fi guy he is). You can always audition mine if you wish!
Thanks as always for an excellent website. I always look forward to the weekend update. My only real criticism is that there is no way (that I can see) of sorting your extensive test "database" by date so I can track the new additions.
All good wishes,
PS. My comment on Martin Bastin puts me in mind of a series of articles you could run. There are any number of interesting "alternative" hi-fi people in UK. Martin, Glenn Croft and Guy Holdsworth immediately come to mind because I've been privileged to spend quality time with them. You could probably add Len Gregory, Richard Lord and others. I bought my first real speakers from Guy, and my current Forte IIs from him as well. Glenn has maintained my mono'd Leak Stereo 20s for a few years since the sad demise of another character, Peter Bruty (what a listening room he had!). Martin has now semi-retired to a lovely house up a hill in the middle of the country but still does all the great engineering work he's renowned for.
There's a little history of Peter and Glenn on eminentaudio.co.uk but I'm sure there's more to be said. This is one of the joys of non-hi-fi shop UK hi-fi -- the opportunity to meet real characters and benefit from their expertise, enthusiasm and (usually strong) opinions.
Peter - E-mail: peter-ward (at) btconnect.com
LC
Dear Peter,
Thanks for the precious and positive feedback! We need that. As for sorting out new articles, just follow the What's New page: new articles are labelled by date. Better than nothing, I'd say. Perhaps we could include labels on the reviews list...but we're lazy lads, ya know :-)
As for articles on alternative UK HiFi designers...well, that could be an idea. Actually, our Inter.Views section needs some serious update.
Lucio Cadeddu
Experiment with Belden 1813A
Dear Lucio,
Long time no write! A long time ago, I wrote in to ask about computer audio. Now I'm back with something cable related...
Part one
I once had a pair of RCA analogue interconnects made from the leftover lengths of Belden 1813A microphone cable I had in the storeroom. Reason? To make a spare set of interconnects. F.y.i., the 1813As were terminated as they are, with RCA
plugged soldered straight to the cable and grounded on one end only. And f.y.i., the guy at my cable shop did it, not me, for I don't own a solder.
Do you know of anyone who has used the 1813A as interconnects?
The sound? Overtly sharp and very, very rough to the ears! Only
percussion sounds good with them extremely tight and cold.
Part two
The 1813As have been lying in the storeroom until recently. Not thoroughly satisfied with my sound system (player from Marantz; mixer from Behringer; active monitors from Wharfedale Pro and cables from Canare. I shall not name the culprit but I believe it lies close to the source), I decided to turn dissatisfaction into action. What if I could modify the old 1813 As and see if that could improve things?
After experimenting, I ended up with my present modification, which just consists of an extra 1813A conductor attached to
each end of each existing RCA plug. F.y.i., I still have no solder, so I unscrewed the top screw on each end of each plug,
inserted the new conductor and screwed it back! In short, each interconnect now has two 1813A conductors and one ground.
Again, there's no twisting, nothing fancy. The sound now? The 1813A tightness is still there, but this
time the overall extreme cold harshness is replaced by a focused and tightened up sound. It still is on the cold and
hard side, but it is now listenable as opposed to unlistenable.
Only after comparing the modified 1813As to my present Canare GS-6s did I get my reality check. The new Beldens made the
Canares seem wishy-washy and less focused! Please note that you'd have to concede that my new Belden is no pedigree breed
and still would not make my old 80's CDs sound like new CDs, nor would it completely tame the Marantz. Nevertheless, I am
extremely pleased, having turned old junk into something that has value, considering the limited hardware I had to work with. Please note also that the Canares might not be sounding their best because they might not have been terminated correctly for unbalanced IC use (it is non-directional, with the shield grounded at both ends).
Thanks for reading the long story...
Would you have any recommendations to improve on the formula I had recently discovered?
Regards,
Ian - E-mail: nemesilius (at) yahoo.co.uk
LC
Dear Ian,
thanks for the tip! Instead of flogging a dead horse :-) why don't you buy a soldering gun? It might prove to be extremely useful as you could build some very good DIY recipes, such as our new TNT Shoestrings interconnects, for example.
Keep us updated!
Lucio Cadeddu
NAD 3020 different versions
I was just reading this review as I own a NAD 3020e, actually two of them, one just purchased recently for my son. Can you tell me the difference with the 3020. The unit I have was purchased new by me in 85/86. Its front panel is all black the back is flat no "shelf".
Do I have a European spec unit? I'm just getting into building full range speaker units probably Fostex or Monacor's in Terry Cains Bigger is Better cabs any idea how they might sound?
Mark - E-mail: markbazinet (at) ns.sympatico.ca
LC
Dear Mark,
the 3020 has been one of the longer lasting integrated amplifiers in the history of HiFi. Born in the mid 70s as "Series 20" it has been subsequently modified and improved. Even a 3120 audiophile version was released and, by far, that was the best sounding 3020 ever. Yours is one of the latest models (3020e and 3020i) right before the end of its life. The NAD 302 replaced all the 3020's. Your 3020e certainly sounds better than the original 3020, no doubt.
It is a warm, dynamic and solid performer so I think it can be used even with fullrange designs such as the ones you intend to build.
Keep us updated!
Lucio Cadeddu
Arm design ramblings
Dear mr Husband,
With interest I read your feature on this article.
However, you are completely in error claiming that: "Rega upset the applecart by taking a radically different approach.
They had a successful turntable and were looking for a tonearm to replace the OEM one fitted at the time. With a market already there for the turntable package they took the risk in producing the worlds first tonearm cast in one piece".
View this link, and please realize that Rega simply stole Alphason's way of manufacturing an arm that still outshines almost anything on the market, regardless of price: http://www.hi-fiworld.co.uk/hfw/oldeworldehtml/alphasonhr100s.html
Rega simply ripped Mike Knowles business right out of his hands, and yes: Rega arms are better than Linn's, which imho cannot even match even an SME S2 on a decent deck. And, btw: All Alphason Arms were made in the UK.
Having said this: I have a "standard" Heybrook TT2 fitted with the superb Alphason HR 100 S-MCS, and this combo blows any madly upgraded and/or modified Linn Sondek right out of the water within the first two bars of music.
I have tried out SME 4, SME 5, Kuzma Stogi and a variety of Origin Live Arms, and I am comfortable to claim that I have never felt anything play me the uncoloured music better.
Oh, yes, I am a sound enginer with 25 years of experience, having done live sound for some of the major international jazz legends, including Chet Baker, Putte Wickman and James Mooney.
Kind Regards,
Conny - E-mail: conny (at) lcraudio.com
GH
Hi Conny,
Hate to say it but the Alphason (which I used to own and admire greatly - it is truly a superarm and capable of taking on the arms you mention) is utterly different to the Rega.
The Alphason was made from a titanium tube which is cut and then flattened to form the headshell - i.e. it is NOT cast in any shape or form. The Rega armtube and bearing housing (note - it is only the armtube and headshell that are continuous on the Alphason) are cast i.e. liquid metal poured into a mould...
The implication that the Rega arm is anything to do with the Alphason is frankly ludicrous and the idea that Rega "robbed" Alphason of the design is equally erronious, the two arms are totally different. There is an arm made with a similar structure to the Alphason but as I don't know the history behind it I'm not going to be throwing libellous comments around...
I suspect after reading the Hi-Fi World article you got hold of the wrong end of the stick, something which I saw as a danger when I read the original a few years back - throwing accusations around and not having the courage to name names risks this kind of misinterpretation - it's sloppy journalism at best, cowardice at worse.
One of the seminal moments in my hi-fi education was hearing an LP12 make music whilst a TT2 just played records - both with the same arm - the Alphason is why your set-up is so good.
Cheers,
Geoff Husband
Hi, Geoff!
I certainly seems to have got the wrong end if the stick! My source control needs improving...
My sincere apologies for any excessive harshness on my part! Interestingly, you nail just the point why the Sondek is an inferior deck: the TT2 reproduces what is on the records, ie is closer to the master tape, while the Sondek is making something up that just isn't there. I think the term is "colouration"...
Did you now that Swedish Linn dealers refused comparisons with similarly-epuipped TT2's back in those days?
Anyway: Thanks for the information!
I wish you a nice weekend!
Best rgds/Conny
GH
Hi Conny,
Thanks for that - I'm not irritated by your original letter, rather the article you read. By incorrectly stating that the Alphason armtube was "cast" it meant that anyone reading the article would automatically assume that either SME or more likely Rega were guilty of immoral business practices - a serious accusation and in this case at least they are completely innocent. It's perhaps a lesson to all of us who write for public consumption.
Cheers,
Geoff Husband
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