Suspension set-up question

[Rich666]

Done a search but not really found the answer I'm after (maybe it doesn't exist!)

Basically a simple question: when setting up the 'bounce' on any suspension deck is there a rule of thumb in terms of stiffness and sound?! I.e very firm bounce = dull but solid fast mid? (made that up as an example)

I know the Internet is a wash with set up info ranging from the mildly amusing OCD to the utter extreme crazy people

Just wandered if maybe some one could give me a more layman's definition or is it completely deck dependent?

 

[Mr Pig]

What sort of turntable is this again?

 

[Rich666]

Well my deck is a Thorens td160 but my question broader than that. Is there a general rule of thumb?

 

[Mr Pig]

Is there a general rule of thumb?

Yes and no. What you're trying to do is more or less the same but there are a wide variety of suspended decks with completely different suspension systems. Your deck is very similar in layout to the Linn LP12 so a lot of the advice for the Linn will be true for your turntable.

I should point out that the setting of the suspension is not as critical as it's often made out to be. Sure, if it's bad it'll hurt the sound but not as much as other things like fastener tightness.

What you are trying to do is set the suspension so that it isolates the suspended parts from the outside world as well as possible. Obvious, but the way to do this is to have it so that all of the springs respond to input in the same way and keep the platter level and stable when subjected to vibration.

If you google 'linn bounce' you'll find some videos. You'll see that the suspension moves straight up and down like a piston when pushed down and let go. It does not wobble sideways or rock like a boat. This is what you want to do and it's not that hard. Basically, if you get everything else right it will happen.

Firstly, the hardware. You might be able to fit later Linn 'black' springs and grommets to your deck. These are tuned differently to the earlier ones and are also ground flat on their faces. They should sound a bit better but more importantly they are a heck of a lot easier to set and tend to stay set. You might have fit longer bolts, as I think the subshassis and platter on the TD160 might be lighter than the LP12s, but it should work and should be better.

Secondly, and a lot of people miss this, the bolts need to be straight. If the three long bolts the springs hang from are not straight the springs will not sit straight and you are never going to get the suspension to set or stay set for long. Linn have a special tool just for straightening the bolts.

Without it, it's a total pain to do but you need to do it. The best way is to strip the deck, place it upside-down and level the plinth. You can then use small spirit levels to see if the bolts are vertical and bend them into place if they're not.

Then put it all back together. You'll need to find some way to support the deck that allows you to access the underside.

You can make a jig but I've used four paint tins many a time. Not ideal but works perfectly well. Level the plinth exactly. Now with the arm, cartridge and cables fitted, adjust the springs until the platter is exactly level too.

Next you set the bounce. Before you start setting the springs you need to address the two other things that connect the subshassis to the plinth, the arm cable and earth strap. The earth strap shouldn't be a problem, you want it thin enough and hung in a way that does not impede the movement of the suspension. The arm cable can be. It needs to be 'dressed' so that it doesn't pull the suspension to the side or effect the vertical movement of the suspension. How you do that will depend on the thickness of the cable and where is sits within the deck. What is your arm cable like? Got any pictures?

 

[a8ch]

Mr Pig is completely right here, and offers some good advice. The TD160 stock springs are decent, and chosen for the smaller (hence lighter) armboard.

Using springs designed for the LP12 with its heavier platter and armboard may be detrimental, I confess though Ive never tried them. What does give a big improvement for nothing is removing the foam inserts in the springs, if they are still there.

As stated in Piggie's post the platters travel should be entirely linear in motion. If you can't achieve this, switch the springs around. Also twisting the springs in situ often helps too, then try again. This last tweak may need several attempts on each spring so be patient

 

[Rich666]

Some top info there cheers guys!

Just to play devils advocate for a second and with no intention of starting WWIII....how much audible difference do you think there would be between a 'well' set up deck and 'a perfect' set up deck with 100% dream bounce! Do you think the listener would tell in an A-B test situation?

I don't have any pics of the arm cable at tho mo mr. p but I'll take some soon

The bounce on mine is rather good at the mo...I think! I'll see if I can get a quick video on my iPhone on here (might be useful for other owners)

 

[simon ess]

I've been reading quite a lot about this lately in preparation for when I pick up an old Thorens TD150 in a couple of weeks time.

It does seem complicated, but Mr Pig has summed it up and simplified it wonderfully.

Thanks Mr P.

A couple of other things struck me from my reading.

1. The suggestion is that it's easier if you make sure the ends of all the springs are pointing directly at the central spindle.

2. The ideal bounce lasts between 12 and 15 seconds. Apparently this is achieved by small, identical turns of each spring nut until the desired bounce is achieved.

How this will work out in practice remains to be seen when I try it.

 

[Rich666]

I fancy a td150 to sit alongside my 160...but that's a bit extravagant lol

I have spent the morning re-tuning my suspension and think I'm getting there it's not really rocket science just a case of having a little patience and trial and error...cup of coffee helps too!

I think I've been to too many loud gigs/festivals to really hear every nuance of change after messing with hifi stuff...I just don't seem to have the ear...but I know what I like and the td160 really suits my needs

 

[a8ch]

I think I've been to too many loud gigs/festivals to really hear every nuance of change after messing with hifi stuff...I just don't seem to have the ear...but I know what I like and the td160 really suits my needs

Hence when I got fed up with the fiddling, I stored mine away rather than sold it.

 

[Rich666]

A wise man! see you at the bar?

I do love my records and my collection but I'm not sure I have the required mind/patience to go to the extremes some people do, however I find my own system (td160 with tp16 tone arm with denon dl110, rotel ra-03 amp and rega r3 speakers) keeps my foot tapping and me listening to music looooong in to the night; I think that's all a hifi can really do.

Even my wife (of 11 weeks!) enjoys listening to her fleetwood mac LP's on it and we both enjoy collecting weird and wonderful records from our travels
Maybe the world of hifi is split...similar to cars...some want and strife for the ultimate in perfection and refinement in speed and others are happy flinging an Xr3I around some corners...IMO neither are wrong

 

[Mr Pig]

To pick up where I left off:

Once you get the arm and earth cables not hindering the suspension you need to adjust the springs. Bounce the deck and look at how 'pistonic' it is. Try to see which corner if any is moving sideways and adjust that spring.

To adjust the springs you simply rotate them, trial and error, until you get them all in the position that gives the bounce you want. The best way to do that is to hold both of the grommets and turn the spring and both grommets together. However you do it you want to make sure that the spring is not twisted around and held that way by friction against the grommet. Imagine you held the bottom in place and twisted the top round and the pressure and friction stopped it from twisting back to its natural position. That's what you want to avoid. If you set it up with twisted springs it won't say that way. The springs will work their way back round and your setting will be out.

Some top info there how much audible difference would be between a 'well' set up deck and 'a perfect' set up deck

Not much.

it's easier if you make sure the ends of all the springs are pointing directly at the central spindle.

I've never heard that. You virtually always need to rotate the springs anyway so I can't see how that would work. Remember that the springs are not under even compression, the weight is not central between them.

The ideal bounce lasts between 12 and 15 seconds. Apparently this is achieved by small, identical turns of each spring nut until the desired bounce is achieved.

No, I don't get that idea at all. The length of bounce will depend on a lot of variables and I don't see how you could set an 'ideal' that means anything. The weight of the suspended mass (which even on the same model of deck will vary with different arms), spring rate and how hard you prod the thing! And the spring nuts alter the hight of the sub-chassis, nothing else. They don't effect the spring rate or compression, turning them just lifts the whole sub-chassis up.

I'm getting there it's not really rocket science

No, it isn't. It's just a record player.

keeps my foot tapping and me listening to music looooong in to the night

Being married can't be that good then eh? ;0)

 

[simon ess]

Aaaagh!!

I do loads of reading, think I'm starting to get my head round it, then someone who's actually done it says it doesn't make much sense.

I've found stuff like this:
Turntable Forum • View topic - Td150 Suspension Tuning: How To Achieve A 15 Second Bounce

But, Mr Pig, I haven't even got the TT yet so I'm in no position to talk.

Thanks for the excellent info. you've provided so far.

 

[Rich666]

HAHA Mr. P all that stops when your married LOL

 

[Rich666]

update: Thanks to the info on here i've got mine bouncing better than ever before!!

@Simon ess: I wouln't worry too much, i did the same as you and read so much info (a lot of it conflicting) on the net that i thought setting one up was brain surgery!! It really isn't...at the end of the day its three springs supporting a bit of metal, its really a case of pretty simple trigonometry. I quite enjoy it

 

[simon ess]

@Simon ess: I wouln't worry too much, i did the same as you and read so much info (a lot of it conflicting) on the net that i thought setting one up was brain surgery!! It really isn't...at the end of the day its three springs supporting a bit of metal, its really a case of pretty simple trigonometry. I quite enjoy it

Thanks Rich. I always have learned best by just doing things, so I'm really looking forward to it. I pick the TT up a week tomorrow.

 

[Mr Pig]

think I'm starting to get my head round it, then someone who's actually done it says it doesn't make much sense.

Well, I've never heard that before so I've never done it that way. Maybe it works, all I'm saying is that I don't get it. I know a bit about these things but I don't know everything. That's my wife's job! ;0)

I thought setting one up was brain surgery!! It really isn't.

No, it's not. A lot of people like to make out there is some kind of black art to it, mainly the people who want you to pay them to do it, but it's only a record player. A bit of logic, common sense and maybe trial and error and it's no big deal.