lash up lenco

[cressy]

bloody kids!!!!!!!!!!!! yet another knackered cart. the coral has a lovely shaped canteliver now. the missus in a fit of generosity (for leaving the room at the most inappropriate time methinks) has bought another cart though. i dont know a damned thing about the linn trak mc though. she looked for mc cart on ebay apparently and bought the first one that came up. i wonder what its like. shall find out soon enough

[Paul Barker]

My son did in a £1,000 cart once but I couldn't own up to what it had cost me. I remember when one arrived from the usa and she had to pay customes of £160 but didn't realise she was only paying the customs charge, she was mad with me for paying £160 for a cartridge.

She has no idea.

Fortunately the valves I bought in those days have increased sufficient to counteract the sheer madness of the other spending.

At the moment I have stepped asside from the madness of it all.

[cressy]

having left the lenco alone for the last week or so after sorting out the hum to a reasonable level, it started annoying again. the hum was masking another noise id heard before on the lp12 idler project. the damned thing was transmitting motor noise into the plinth, and vibrating the arm tube. as soon as the needle hit the record i got a buzz, similar to the hum off the phonostage. with the lp12 idler this caused me to abandon the project and sell the bits off. it was impossible to cure because it had to have solid motor mounts. ive cured this on the lenco by simply removing the lenco spring and grommet suspension and gluing a set of great big rubber cones onto the underside in their place. these are tapered so just sit straight in the original cups on the plinth. incidentally, these were the feet off the lp12 idler. i hate it when the thing youve spent time making starts to p@£$ you off. takes the fun out of it.

[cressy]

well........ so much for the linn cart. what a horrible bloody thing it is. the thing sounded absolutely awful. it seems like its running into the wrong load for a start as there was really curtailed treble and fat slow honky bass. there was no atmosphere or stage width or depth just an extremely muffled wersion of what should be. the exact opposite of what i expected from a linn cart. i expected screech, but there was nothing of any merit. ive put the coral back on after some hart stoppingly fiddly surgery with tweezers and a magnifying glass to straighten the canteliever. it doesnt seem to be eating my vinyl so i think it went quite well. it was bent anyway so nothing to lose. even emma reckoned it was horrible though and she couldnt care less what it sounds like. i think i shall keep it for now though as in the near future im planning to attempt my first electronics build on an rca phono stage, or something as simple as possible so could try altering the load. back to the coral and its really nice now. the thing even looks less lashed up with a severe lack of zip ties on the arm. i can now enjoy it at last!

[cressy]

i came across a strange problem today on the lash up, i was pratting about to see if a bit of setup work would make the sound a little less woolly and curtailed at the top end. first things first i cleaned the stylus with the at buzzy thing, raised the arm slightly at the pillar and retightened anything with a bolt on it. i then went to check the tracking force. what!?!? it read as tracking at 4.8g with the gauge on the platter. good god no wonder it was so woolly. what struck me as odd though was that putting the gauge on the plinth gave a reading of 1.8. then it hit me. the arm was reaching its natural centre of gravity just after it was hitting the gauge. the arm wasnt hitting the plinth even though it was balanced. it was down so that the cart was smack in line horizontally with the bottom of the counterweight. the reason is that adding the rubber blocks to the motor unit has raised it by about 30mm so the arm height has gone up equally, raiseng the cog too. its a lot better now with the cart tracking correctly. perhaps that was the problem with the linn cart. bloodyell. once again i feel rather sheepish..............

[cressy]

another little tweak was done today while i has some down time, (no list of things to do on mi day off? whats the world coming to!) i damped the entire motor unit with 2 layers of that bitumen stuff that cars have in their doors. rather a good tweak as it sharpened everything up quite a bit and released more detail from the deck. at the last owston having a look at wills lenco i saw that hed done some damping under the platter with the same stuff. a great tweak and well worth the 2.50 for a sheet of the stuff. i suspect it will work on any deck this one!

[Andrew]

Hi,

Where did you get it from? I have some chassis that could with a bit of damping on the lids.

thanks,

-- Andrew

[Greg]

I've used this stuff for years for TT's, amp chassis' and inside CDP's. I thought everyone knew this trick. Used to be easily available from Halfords but possibly not so now. They suffer the same syndrome as Maplins. Search out Automotive suppliers in your area and you should be able to pick it up easily. Often comes as 10 self adhesive sheets approximately A4 size. Alternatively, search Google on Bitumen damping pads etc and it should be readily found.

[shane]

WD do a heavier thicker version called Soniqs PDC on their website.

http://wduk.worldomain.net/acatalog/Speaker_Parts.html

[cressy]

i got this from my local motosave, it was right out of the way covered in dust so as greg says, its a little harder to come by than it used to be. seems to be better to go into the smallest scruffiest shop possible to get it! halfords had none, charlie browns the same even though they had every car speaker imaginable!

[simon]

rather a good tweak as it sharpened everything up quite a bit and released more detail from the deck.

I've used the same stuff on the back of my speaker magnets and basket to the same effect.

[cressy]

i'll have to try that one, plus some different cabling when i can be bothered, theres a couple of other tweaks im thinking of trying such as damping the platter 'like will done' and that broadcast tt bearing ive got thats sat there doing nowt. maybe a power supply too as i can now hear the damned thing wowing. it only showed up on a vinyl copy of wish you were here on the crazy diamond track, bit i know its there. its always the same int it!

[Will]

Ant.. do the platter.

[Greg]

Yep, do the platter but think about balance. As you apply the pads, try not to spoil the dynamic balance of the platter spin. Even distribution is the key!

[cressy]

thats what put me off in the first place, the platter has all the balancing already done (as it should have) but i didnt want to affect this. though i suspect this shouldnt really make that much difference to its balance if done as will did with the added damping done close in to the spindle., i dont know if this was the method employed on yours will but the way it looked is that the damping was added with the idler set at 16 rpm and then the damping added from there into the centre. i could add a complete sheet to the top of the platter instead but im not sure. too much damping and the music goes dead. thats why of you look on the pic of the underside theres one layer of damping then several raised sections. i originally just put 2 complete layers on but it was ..... well abit crap. lost all the joi de vivre it had. i left the 2 layers on the areas i though would be most problematic, i.e the area 13" by 3" to the right of the platter where the arm was originally. the reason im abit reluctant is that the sheets are a b£@$%£d to get back off once stuck. what do folks reckon?