Lazy Sunday afternoon ...........
When you play records in the sunshine, don't forget your parasol.
It's August 2004 and the GL72 I bought on ebay arrived last week just in time for some good weather, well one day. Sunday morning at the car boot sale turned up an ancient Rotel 150 tuner amp. I noticed it had 2 tape circuits (ideal for experiments with my reel to reel decks) otherwise I wouldn't have bothered looking. When the seller said 'one pound' I didn't haggle.
Sunday afternoon, and to test out the Rotel I used the 72, which I had set up on old BBC computer monitor stand (see below). Trusty Sennheiser phones and deck chair complete the ensemble. That morning I had also picked up a few discs so now playing is the Stones. Notice the FM dipole attached to the tree :-).
The deck has a little motor noise on this plinth, but using the M55e cartridge the sound is solid with strong bass lines. This arm/cartridge combination pulls lots of studio detail from the vinyl. Very nice.
The Rotel turns out to be 'a ok' and sounding great (for an old 'un) on phono and fm. So good in fact I listened longer than planned, bit of a rush to finish the day's gardening tasks.
The GL72 Story (or one wet Wednesday afternoon)
I originally bid for this deck to use for spares. The arm was broken and missing the headshell. On first test the motor and bearing were fine, and it had the all important metal idler wheel. I thought I'd see if it sounded ok by fitting a Connoisseur SAU2 arm. I have resisted cutting any of my other Lencos, but figured the generally tatty condition of this made it a suitable case for treatment. The SAU2 arm requires a spindle to pivot distance of 199/200mm. The GL72 has a 210mm spindle to pivot distance. I used a hole saw to cut a new hole at the correct distance, keeping the line of the original in order to use the arm rest and lift/lower. The original lift lower device on the Sau2 is awkward to use, so using the Lenco lift/lower is a big improvement. I put an MDF arm board underneath the deck plate, and a small sheet of plastic on top to hide the unused hole. (Thanks to John Booth for his help with all of that.)
This image shows the hole for the Sau2 on the left, and the mdf underneath. The small hole on the right is a pilot hole at 220mm, ready to drill out for a longer arm like the Rega or ADC Alt1. Adding these extra holes to a Lenco makes them very versatile, taking it one step further and creating a long slot would allow easy arm changing and adjustment. It's worth keeping in mind that the light platter decks have deeper platters, much higher from the deck surface than the heavy versions. This makes vta adjustment less of a problem.
I removed the aluminium trim from the front for the all black look, inspired by Tom's excellent Vitesse . Ok it's rough, but I wasn't expecting to have to paint it! ;-)
This pic shows the base of the SAU2 arm, and the mdf arm board under the metal deck plate. The plug for the arm cable just misses the lift/lower mechanism - phew! Notice the earth connectors on the main bearing and the motor, the arm earth wire had been cut short, so it is extended to reach the deck plate earth screw.
| - And Then ............ |
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I later tried the deck with my main system and the B&W DM12s highlighted the motor/mains rumble. Playing a few favourite discs confirmed earlier findings, fast bass and transients that identify who's playing what, and where.
Some more layers for the plinth I think. I guess I'll have to get another for spares ...........doh!
Important discovery
While fitting the deck to a new plinth I found the motor suspension was not bouncing like it should. On closer inspection the top springs on the posts near the main motor body, were both broken. I don't know how this could have happened, maybe impact damage at some time in it's long life.
Left are the 2 nose springs, centre and right the main body springs. One of the broken pieces far right. The broken springs were allowing the motor body to touch the deck plate. This is obviously the source of the motor noise I've been getting from this deck. Fix in progress ............................ |
| - Getting there .................. |
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I spent a couple of hours trying to shape various springs to fit the motor, then thought 'what if I stretch the old ones?'
I figured if they broke I'd have to get a new set from T&G, but they did stretch and fit back in a treat. Refit the motor and luckily the suspension now works as it should. No droning. Time for a shoot out with the GL55.
Looking round the workshop, and having borrowed the idler wheel from the B55 for the GL55 test, I decided to take it's plinth as well for this GL72 as they are identical designs, just different trim. Soundwise the GL72 with SAU2 was better than the B55 with JVC arm. (The B55 project is on hold waiting for an arm collar, which hopefully will get it up to scratch.) Here is the 72 in the plinth, I made a new arm board in mdf painted black. A couple of simple tweaks have made this deck sound much better. See below.
Tweaks
When the Oracle turntable first came out some reviewers preferred it to the Linn. Shock! Horror! One of it's 'features' was a rubber ring set into the platter. They called it a 'peripheral wave trap' or something similar. I made one of these (very easy) in the late 70s for my TD150, and fortunately it fits the 72 a treat. Apart from adding some 'flywheel effect' weight to the periphery of the platter, it also stops it ringing like Big Ben.
Another popular 70s tweak was adding a glass mat to lightweight platters like PL12Ds and similar Japanese decks. You guessed it, I got one of those as well. It makes a big improvement for the lightweight Lencos, improving the sound of piano music in particular.
This has been a useful learning process for me. Adding holes to the Lenco top plate is not as difficult as I had imagined, and it immediately opens up the potential for using different arms. I definitely prefer this to cutting off the corner, because something tells me the integrity of the main bearing/arm interface is worth keeping.
It's not the perfect fix for arms that won't come down low enough to get proper vta though, they have to be mounted below the deck plate. There's always two mats, or cartridge spacers. Hmmm......... now for something completely different ........... here scroll to the last pictures. |
