LP12 Radikal Problem
Posted by: Peder on 06 May 2018
I said earlier in some thread, that I shall write a thing about the LP12, that maybe can help many here,.....well here it comes.
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A year ago,or maybe longer back in time (time goes so fast), we find this issue with the LP12.....if it has the ◾Radikal power-supply.
We have tested alot, and we have problems to understand, why some LP12's on Klimax level sound so bad. It was a guy in our group who find this issue/problem.After we find this problem, we have talked to the best Swedish retailers on LP12's,they didn't know about it. Now at these days, many retailer/dealers knows about this, but not all. We have also talked alot with Linn,....and Gilad (MD) about this subject/issue,but thats between them and us.
The dealers/retailers who knows about this issue, are trying to solve the problem for there costumers. Peter Swain Cymbiosis, Tomas Okeef USA ect,ect.
◾Fredrik Lejonklou has done a good write-up about this issue on his forum,I have talked to Fredrik,and he says that its ok to use his writings about this issue. It's better then write it all over again ????. There you also have pictures from the inside of the LP12, so you can see the problem for yourself,.....(I have problem to post in pictures).
See Fredrik Lejonklou's forum under "On the Inside"...subject "LP12 Radikal problem for the pictures.
If you don't know about this issue/problem, and have an LP12 with a Radikal power-supply,......then you must go to your dealer so they can control your LP12.It's about 50 % of the LP12's with Radikal's who has this problem. BUT FIRST,...read this information about the LP12 Radikal problem.
???? ???? ????????LP12 RADIKAL PROBLEM ???? ???? ???? ????
Everyone who has a Radikal motor on their LP12 and either a Trampolin or a Urika needs to read this. If your retailer does the service, specifically ask him about this issue! If you service it yourself, check this!
The Radikal motor is housed in a big can, which is very deep. Below the can is the left rear trampolin foot and the distance between these two is very small. On some LP12's (currently 2 out of 4 that I have checked), the can actually rests on the foot. This causes the LP12's musical performance to drop significantly. Bass gets sluggish and untimed, music becomes a bit "seasick" instead of rock steady. The following picture was taken with a GoPro camera by Erik:
????Here you shall have the picture from the inside of the LP12.
Radikalhousing.JPG (164.2 KiB) Viewed 891 times
What you see in the picture above is
To the left: Part of the left suspension spring,
Upper middle and right: Keel subchassis,
In the middle: Radikal motor can with its aluminium lid at the bottom,
Below the can and its bottom lid, on the left side: The rear left Trampolin foot assembly.
If you have Radikal and Trampolin, there is also a screw on the Trampolin foot that protrudes right below the can. Unless this screw has been grinded down in length, it's guaranteed to press against the motor can. On the Urika, the feet are rotated 45 degrees to move this screw away from the Radikal can.
One way to test if the can touches the foot is to make a long piece of thin paper that gets more narrow on one side and protrudes through the hole below the arm pillar (picture by Paolo below). Place it on the Trampolin/Urika, install it below the LP12 with a few screws and then place the LP12 on a table, standing on its Trampolin feet. Now pull on the piece of paper to the right of the arm. Is it stuck? Then you have a problem.
????Here you shall have the picture of the paper-test.
Papertest2.jpg (132.67 KiB) Viewed 891 times
If you have the problem, your Trampolin/Urika needs to be moved down, away from the can. I have grinded down the outer perimeter of the Trampolin foot slightly and thought that was enough, but when I did the paper test, it turned out it wasn't - the can and foot were touching. So I have added some wooden strips between the plinth and the Trampolin, which I bought from a hobby store. They had lots of varieties there, so I bought two of every kind. What's needed is a width of 8-10 mm and a thickness of 1-2 mm. On most LP12's I suspect 1 mm will be enough, but there are no such thin strips in my newly acquired collection. With 2 mm, you might begin to get problems with the screws not gripping as well in the holes of the plinth (in which case you can use a longer screw). While I'm sure that different types of wood are likely to sound a bit different, the ones I have which are most uniform in thickness are 8x1.5 mm strips of Lime-tree. They're quite light and soft, so I have removed the old felt strips (the purpose of which I believe is to prevent rattling). I wanted to try Balsa as well, but they varied so much in thickness; 1.2 to 1.6 mm. I don't really know what is optimal, perhaps we can help eachother find out what is?
Wood type?
Thickness?
Original felt strips - in place or removed?
Please note that all plinths are a bit different, so you will need to verify the dimensions on yours. I have a Linn original in maple and used the following measurements when cutting and drilling my four pieces of strips. These strips are for my Trampolin. The front and rear strips are 410 mm long and the left and right are 305 mm. Please note that when drilling, the strip easily cracks. If you clamp it between two other pieces of wood, you can prevent this. Or you might make it by being very slow and gentle. It's good to have more strips than you need, in case you break them.
????Here you have a paper-writings picture.
Stripes2.jpg (136.61 KiB) Viewed 891 times
EDIT: I see now that I forgot to draw the hole in the middle of the rear strip.
I didn't use any glue when installing the Trampolin with the strips lying on each of its four edges. Glue would surely have made it easier, but I felt a bit sceptical of it and the installation is doable anyway. After the installation, the Trampolin sits 1.5 mm lower than before.◾ And the result is a completely transformed musicality of the LP12. Much, much better. ◾
????Here you have the last picture of the Trampolin.
Trampolin.jpg (199.87 KiB) Viewed 891 times
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I hope that,after you have control this,....and maybe fix it. You get the soundquality from your LP12, that you deserved for your hard earned money.
/Peder ????
Adam Meredith posted:Loki posted:fettle LP12s
fettle, drizzle, coulis and curate - back in my day we were happy just to set the buggers up.
Let us move on from the dark ages of monosyllables, limitation and imprecision. Let us, rather, revel in the intricate and colourful wealth of textures and nuance our language affords. The English language is a rich source of synonyms from which we can all choose our preferred and diverse terms: Condition; make ready; put in order. But on Asgaard we prefer the 1674 definition: 'to address oneself to battle' rather than to line or scour. Although, since my LP12 is now setting my ears on fire, one might consider the 1894 usage 'the material used for fettling a furnace' more apposite. Just ask Thor 