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<p><strong><a rel="attachment wp-att-13073" href="http://www.tonepublications.com/old-school/harman-kardon-rabco-st-7-linear-tracking-turntable/attachment/1-119/"><img class="alignnone size-full wp-image-13073" title="1" src="http://www.tonepublications.com/media/1138.jpg" alt="" width="600" height="396" /></a>Welcome to Kludgeville, aka the H/K Rabco ST-7 linear-tracking turntable.* Introduced in the mid 1970s and selling in fairly high numbers, the ST-7 was a brilliant product, which eventually crashed and burned because of reliability issues and a changing marketplace.* It and its sibling ST-6 and ST-8 models introduced linear tracking, or tangential tracking, to a wide audience of music lovers seeking to extract that little bit of extra magic from the record grooves.</strong></p>
<p>Tangential arms were nothing new at the time.* Companies like Rek-O-Kut, Ortho-Sonic and Burne-Jones had fielded products of this nature as early as the mid-1950s.* However, it wasn’t until the mid-1960s that a somewhat commercially viable tangential-tracking turntable, the Marantz SLT-12, became available to the buying public.* As valiant an attempt as the Marantz was, it was doomed to fail as a successful business venture, due to various mechanical problems.</p>
<p>Enter Rabco, the Maryland-based manufacturer of the now-famous SL-8 and SL-8E tangential-tracking tonearms.* Somehow, Rabco figured out a way to make these arms relatively reliable, despite their mechanical complication (i.e. two electrical motors). *These arms found their way onto many of the revered turntables of the early 1970s, like the Thorens TD-125 and Technics SL-1100.* Rabco even marketed a complete linear-tracking turntable in the form of its ST-4 model.* At the time, the ST-4 retailed for $159, while the more sophisticated SL-8E retailed for $169. *These prices weren’t out of line by any means, considering that a garden-variety belt-drive turntable at the time sold in the vicinity of $115.</p>
<p>Even though Rabco was reasonably successful, the company eventually sold out to Harman Kardon.* By 1975, the acquired brand was manufacturing the ST-7, which was embraced momentarily by its dealer network.* I actually owned an ST-7 in 1975 and enjoyed it immensely, but its complication led to frustration and I passed it on to another owner.* So here I am now with a nice example of an ST-7 and it’s working pretty well.* How did this happen?</p>
<p>About a year ago, I was the recipient of three gifts from two friends: a Marantz 2245 receiver, a pair of JBL L100 speakers and the ST-7.* The Marantz and JBLs were easy to sort out and get up to excellent working condition. *However, the ST-7 sat on a filing cabinet for months before I even plugged it in. *I know that getting this thing up to new-operation condition was going to take a lot of patience, so that is what was exercised. *After plugging it in, various problems came to light. *It needed thorough cleaning, extensive lubrication, new belts, new indicator lamps and many, many adjustments.</p>
<p><a rel="attachment wp-att-13074" href="http://www.tonepublications.com/old-school/harman-kardon-rabco-st-7-linear-tracking-turntable/attachment/2-112/"><img class="alignnone size-full wp-image-13074" title="2" src="http://www.tonepublications.com/media/2126.jpg" alt="" width="600" height="407" /></a>I said welcome to Kludgeville and that is not an understatement.* Removing the platter and top panel of the ST-7 reveals a mechanical nightmare that would do Rube Goldberg proud.* And just about everything is adjustable. *But those adjustments must be made just right or the thing simply won’t function properly.</p>
<p>So, over a four-month period, I deal with one issue after another, often creating another issue, which created another.* There were times when I just wanted to hit it with a hammer and be done with it, but I persevered.* Eventually I got it to play records without either malfunctioning or going out of adjustment.* And even though I had the owner’s manual, I was missing the all-important cartridge-alignment gauge; luckily, wonders of modern technology fixed that for me.* A company called Shapeways makes a 3D-printed version of this gauge that works like a charm.</p>
<p>Before putting the ST-7 into service, I did a couple of tweaks that worked out well.* I did some internal damping of the metal casework and I installed a GEM Dandy turntable mat.* I also replaced the crummy molded RCA plugs with high-quality gold-plated copper models. *Another tip for good operation is getting the table to be perfectly level; I have a handy bi-directional mini level that works perfectly for this task.* I use a Shure V-15 Type III cartridge for all of my listening.</p>
<p>First impressions are very promising—the ST-7 keeps its speed stability well and exhibits little signs of rumble.* A tap on the chassis does produce an audible <em>thunk</em>, but that is not too bothersome.* Who smacks their turntable while listening anyway?* The tonearm tracks perfectly straight across all the records that I play, and the end-lift/shut-off mechanism performs flawlessly—promising indeed.</p>
<p>Going with period music, I decide to play nothing but 1970s records.* First up is Chick Corea’s album <em>Crystal Silence</em> (ECM).* The lengthy composition “Sometime Ago/La Fiesta” is thoroughly enjoyable, exhibiting a nice clean treble presentation and good rendering of Flora Purim’s vocals.* Next up is “Miles Beyond,” off of the Mahavishnu Orchestra’s <em>Birds of Fire</em> album (Columbia). *There is excellent punch on Billy Cobham’s drums, Rick Laird’s bass lines are clearly delineated and John McLaughlin’s guitar has incredible bite, while Jerry Goodman’s violin does not irritate.* I move on to the Jan Hammer Group’s album <em>Oh, Yeah?</em> The title cut is very busy with synthesized bass, bass guitar and bass drum, but the ST-7/V-15 combination unravels all of it.</p>
<p><a rel="attachment wp-att-13075" href="http://www.tonepublications.com/old-school/harman-kardon-rabco-st-7-linear-tracking-turntable/attachment/3-100/"><img class="alignnone size-full wp-image-13075" title="3" src="http://www.tonepublications.com/media/3115.jpg" alt="" width="600" height="407" /></a>By this time, I’m into the smiley-face/toe-tapping region of listening. *For the final album, I tee up <em>In Praise of Learning</em> by Henry Cow.* Yes, I realize that admitting to listening to Henry Cow is akin to admitting that you set cats on fire or throw bricks at school busses, but I like the music.* The song “Beautiful as the Moon – Terrible as an Army with Banners,” a paen to oppressed working classes, sounds as good as I remember it sounding when I played this very same record on my original ST-7. *If I remember correctly, the cartridge I had on that one was a Fidelity Research FR-1 MK II. *To achieve similar results with the refurbished table is not too shabby.</p>
<p>If I can criticize the reproduction of this particular ST-7, it is that the lower registers are lacking in weight compared to some modern tables, and the front-to-back staging is a bit compressed and two dimensional. *On the plus side, you get a big, steady left-to-right image, great focus and absolutely no mis-tracking.</p>
<p>Owning one of these turntables is not for the faint of heart.* You either have to be mechanically adept or know a technician who can deal with the various trouble spots.* Most of all, one must have patience.* However, once you have it sorted out, the ST-7 is easy to use, it sounds pretty darn good and it has looks that are way past cool.* I’m keeping this one, which will be mated to the Marantz/JBL system, where it will live happily ever after—at least until it goes out of adjustment.</p>
[Source: http://www.tonepublications.com/old-school/harman-kardon-rabco-st-7-linear-tracking-turntable/]
<p>Tangential arms were nothing new at the time.* Companies like Rek-O-Kut, Ortho-Sonic and Burne-Jones had fielded products of this nature as early as the mid-1950s.* However, it wasn’t until the mid-1960s that a somewhat commercially viable tangential-tracking turntable, the Marantz SLT-12, became available to the buying public.* As valiant an attempt as the Marantz was, it was doomed to fail as a successful business venture, due to various mechanical problems.</p>
<p>Enter Rabco, the Maryland-based manufacturer of the now-famous SL-8 and SL-8E tangential-tracking tonearms.* Somehow, Rabco figured out a way to make these arms relatively reliable, despite their mechanical complication (i.e. two electrical motors). *These arms found their way onto many of the revered turntables of the early 1970s, like the Thorens TD-125 and Technics SL-1100.* Rabco even marketed a complete linear-tracking turntable in the form of its ST-4 model.* At the time, the ST-4 retailed for $159, while the more sophisticated SL-8E retailed for $169. *These prices weren’t out of line by any means, considering that a garden-variety belt-drive turntable at the time sold in the vicinity of $115.</p>
<p>Even though Rabco was reasonably successful, the company eventually sold out to Harman Kardon.* By 1975, the acquired brand was manufacturing the ST-7, which was embraced momentarily by its dealer network.* I actually owned an ST-7 in 1975 and enjoyed it immensely, but its complication led to frustration and I passed it on to another owner.* So here I am now with a nice example of an ST-7 and it’s working pretty well.* How did this happen?</p>
<p>About a year ago, I was the recipient of three gifts from two friends: a Marantz 2245 receiver, a pair of JBL L100 speakers and the ST-7.* The Marantz and JBLs were easy to sort out and get up to excellent working condition. *However, the ST-7 sat on a filing cabinet for months before I even plugged it in. *I know that getting this thing up to new-operation condition was going to take a lot of patience, so that is what was exercised. *After plugging it in, various problems came to light. *It needed thorough cleaning, extensive lubrication, new belts, new indicator lamps and many, many adjustments.</p>
<p><a rel="attachment wp-att-13074" href="http://www.tonepublications.com/old-school/harman-kardon-rabco-st-7-linear-tracking-turntable/attachment/2-112/"><img class="alignnone size-full wp-image-13074" title="2" src="http://www.tonepublications.com/media/2126.jpg" alt="" width="600" height="407" /></a>I said welcome to Kludgeville and that is not an understatement.* Removing the platter and top panel of the ST-7 reveals a mechanical nightmare that would do Rube Goldberg proud.* And just about everything is adjustable. *But those adjustments must be made just right or the thing simply won’t function properly.</p>
<p>So, over a four-month period, I deal with one issue after another, often creating another issue, which created another.* There were times when I just wanted to hit it with a hammer and be done with it, but I persevered.* Eventually I got it to play records without either malfunctioning or going out of adjustment.* And even though I had the owner’s manual, I was missing the all-important cartridge-alignment gauge; luckily, wonders of modern technology fixed that for me.* A company called Shapeways makes a 3D-printed version of this gauge that works like a charm.</p>
<p>Before putting the ST-7 into service, I did a couple of tweaks that worked out well.* I did some internal damping of the metal casework and I installed a GEM Dandy turntable mat.* I also replaced the crummy molded RCA plugs with high-quality gold-plated copper models. *Another tip for good operation is getting the table to be perfectly level; I have a handy bi-directional mini level that works perfectly for this task.* I use a Shure V-15 Type III cartridge for all of my listening.</p>
<p>First impressions are very promising—the ST-7 keeps its speed stability well and exhibits little signs of rumble.* A tap on the chassis does produce an audible <em>thunk</em>, but that is not too bothersome.* Who smacks their turntable while listening anyway?* The tonearm tracks perfectly straight across all the records that I play, and the end-lift/shut-off mechanism performs flawlessly—promising indeed.</p>
<p>Going with period music, I decide to play nothing but 1970s records.* First up is Chick Corea’s album <em>Crystal Silence</em> (ECM).* The lengthy composition “Sometime Ago/La Fiesta” is thoroughly enjoyable, exhibiting a nice clean treble presentation and good rendering of Flora Purim’s vocals.* Next up is “Miles Beyond,” off of the Mahavishnu Orchestra’s <em>Birds of Fire</em> album (Columbia). *There is excellent punch on Billy Cobham’s drums, Rick Laird’s bass lines are clearly delineated and John McLaughlin’s guitar has incredible bite, while Jerry Goodman’s violin does not irritate.* I move on to the Jan Hammer Group’s album <em>Oh, Yeah?</em> The title cut is very busy with synthesized bass, bass guitar and bass drum, but the ST-7/V-15 combination unravels all of it.</p>
<p><a rel="attachment wp-att-13075" href="http://www.tonepublications.com/old-school/harman-kardon-rabco-st-7-linear-tracking-turntable/attachment/3-100/"><img class="alignnone size-full wp-image-13075" title="3" src="http://www.tonepublications.com/media/3115.jpg" alt="" width="600" height="407" /></a>By this time, I’m into the smiley-face/toe-tapping region of listening. *For the final album, I tee up <em>In Praise of Learning</em> by Henry Cow.* Yes, I realize that admitting to listening to Henry Cow is akin to admitting that you set cats on fire or throw bricks at school busses, but I like the music.* The song “Beautiful as the Moon – Terrible as an Army with Banners,” a paen to oppressed working classes, sounds as good as I remember it sounding when I played this very same record on my original ST-7. *If I remember correctly, the cartridge I had on that one was a Fidelity Research FR-1 MK II. *To achieve similar results with the refurbished table is not too shabby.</p>
<p>If I can criticize the reproduction of this particular ST-7, it is that the lower registers are lacking in weight compared to some modern tables, and the front-to-back staging is a bit compressed and two dimensional. *On the plus side, you get a big, steady left-to-right image, great focus and absolutely no mis-tracking.</p>
<p>Owning one of these turntables is not for the faint of heart.* You either have to be mechanically adept or know a technician who can deal with the various trouble spots.* Most of all, one must have patience.* However, once you have it sorted out, the ST-7 is easy to use, it sounds pretty darn good and it has looks that are way past cool.* I’m keeping this one, which will be mated to the Marantz/JBL system, where it will live happily ever after—at least until it goes out of adjustment.</p>
[Source: http://www.tonepublications.com/old-school/harman-kardon-rabco-st-7-linear-tracking-turntable/]