tightening up bass on a pre-cirkus LP12

[mimoser]

Recently I stumbled upon an LP12 on the cheap. You can read the complete story at: http://www.vinylengine.com/turntable_for...15#p385475

As you will also read there, it sounds as if my first attempt at tinkering with an LP12 was not completely unsuccessful.

The main issue remaining between my listening tastes and the LP12 is a rather mushy (boomy?) bass, which is not as well defined as on our TT2. In comparison mids are more lively on the LP12 and it "rocks" a little bit more …
;-))

some pics:



I was told, that the box on wheels the LP12 is sitting on might be a big part of my issue. Our floor is hardwood-parquet though and a nordic table is not a viable option …
I will get a wallmount this weekend, so there are some options I’d like to toy around with.

Please do not advise me to buy a Keel; this is a low-budget approach, which was entirely funded with some other audio junk bought cheap and resold for fair rates. I would like to keep the ball flat on that one.
Selling the TT2 to fund a Cirkus Kit is also not a sexy proposition …

So to give you a basic idea – this is a pre-circus LP12 with spot-welded subchassis. PS is a Hercules/Mose, Origin Live armboard, slightly modded RB251, Pickering XV-15 625e, original Linn cable via Cardas connector at base of arm.

Objective is tightening up the bass rendering of this combo.

Thanks in advance

Michael

[Andy]

(2012-08-03 07:53)mimoser Wrote:  So to give you a basic idea – this is a pre-Cirkus LP12 with spot-welded subchassis. PS is a Hercules/Mose, Origin Live armboard, slightly modded RB251, Pickering XV-15 625e, original Linn cable via Cardas connector at base of arm.

Objective is tightening up the bass rendering.

Thanks in advance
Michael

I did the Cirkus upgrade so long ago that I forget what difference I heard. Probably, I just said "Yes" when my Linn dealer suggested it.

25 years later, I've developed my "ear", got much better speakers and amplifiers, upgraded my LP12 still more ... and learned to think for myself.

2 things that gave me substantially better bass - deeper, not only better controlled - are:
1. A Lingo (compared to the Valhalla). I bought an L1 in the 90s ... and then got a further bass improvement when I upgraded to a late-model L2 in 2010 or 11.
2. Having a custom-built, extra-thick plinth made for me (30mm thick planks instead of 23mm).

Good luck,

Andy

[Mikeg]

As you are doing this on the cheap there are some basics that I would suggest you need to look at:

1. Setup - getting the deck setup well can make a huge difference. If you are doing it yourself check the 'LP12 Set-up - a brief overview' thread.

2. What the LP12 sits on is also very important. Linn recommend 'light but rigid'. Cheapest 'ok' one is probably an Ikea 'Lack table'.

3. Pickering cartridges do not tend to be used with Linn turntables. You might want to look at Linn's own Adikt.

4. If you are able to spend some money a Cirkus is a good place to start and would tighten up the bass.


Mike

[class a]

I added a Cirkus upgrade to my 1986 Linn about 3 months ago and the bass became much tighter and focused. Well worth the price.

[Dr_Eddie]

The best way to start is first place the Linn on a light coffee type table or better still a wallshelf with decoupled board on spikes. Then ditch the brush at the front of the Pickering. Make sure the TT has a free pistonic bounce, when you tap the platter lightly up and down.

If not get it serviced at a Linn dealer. By now you should have really tight, fast bass.
Might be an idea to ditch that cartridge if not.

What Mikeg said above is pretty much spot on though. +1.

[tokenbrit]

Have you tried it without that brush 'thingamee' attached to the cart?

[mimoser]

(2012-08-03 20:02)Dr_Eddie Wrote:  The best way to start is first place the Linn on a light coffee type table or better still a wallshelf with decoupled board on spikes.

A Wallshelf will be coming tomorrow; would you suggest a thin board or something more substantial on top of the spikes?

(2012-08-03 20:02)Dr_Eddie Wrote:  Then ditch the brush at the front of the Pickering.

Will try that, but since it is no problem on the tt2, I did not suspect it might be an issue …

(2012-08-03 20:02)Dr_Eddie Wrote:  Make sure the TT has a free pistonic bounce, when you tap the platter lightly up and down.

As far as my noob perceptions go, this is the case; it even returns to pistonic, when moved laterally …

(2012-08-03 20:02)Dr_Eddie Wrote:  If not get it serviced at a Linn dealer. By now you should have really tight, fast bass.

That is the finishing touch I am going to do if I decide to keep it as primary turntable, which I favor very much because of my personal history with it. The TT2 is just another second hand table emotionally. I just wanted to see how far I get on my own and kind of make sure the LP12 will be an improvement. I am a sceptical kind of guy,

(2012-08-03 20:02)Dr_Eddie Wrote:  Might be an idea to ditch that cartridge if not.

The cart – or at least its sibling performs well on that other table in a similar setup, so cannot be all that bad – mids and highs are beautifully and absolutely comparably there …

(2012-08-03 20:02)Dr_Eddie Wrote:  What Mikeg said above is pretty much spot on though. +1.

investing in expensive upgrades is finacially not possible for me at the moment, so getting the LP12 up to the TT2s performance with room for improvement in the future is my immediate goal.

Thanks for all the input; your feedback is very helpful and to the point I did obviously not see in my first attempts!
Next thing is absolutely leveling everything out on a wallrack …
Michael

[Andy]

(2012-08-03 20:02)Dr_Eddie Wrote:  ... or better still a wallshelf with decoupled board on spikes.

Spikes couple the board to the wall-shelf.

Regards,

Andy

[Dr_Eddie]

No, spikes decouple the board. The sharp point ensures that minimal energy is transmitted through the spike. The Naim Fraim is a prime example of decoupling through the use of finely engineered spikes and cups. If you wanted to couple the two items you'd screw them together.

The board the Linn sits on should IMO be as light and rigid as possible. As a starting point try some MDF about 5mm thick. The bottom line in all this, is that, the Heybrook TT2, although a fine TT was no match for the Linn LP12, and you may find a more revealing cartridge will expose the differences far more ruthlessly.

[Braden]

After you're done fixing your rack and still need more improvement a Trampolin 2 is a fairly inexpensive way to tighten up the sonics.

I also agree with the above poster that recommended removing that 'pre duster' off of your cartridge. The only thing it can do is mess with tracking stability and force.