Also,what makes my Krell so special than there is not much undamping required? ...
Hi Florian,
Yes, don't they look (and sound) sweet?
To quickly answer your question, the putty adjustment "tunes" the whole bass system by making the passive radiator "heavier or lighter".
In a perfect bass system, all the drivers would stop and start "instantly". But we live in the real world where all the drivers have mass (weight) and when they move back and forth, there is a small amount of time when they are changing direction.
Due to this the drivers are actually designed to stop and start.
But, if they are too light, then they respond too quickly and don't address the right frequencies.
On the other hand if they respond too slowly, they sound bloated and wooly (fuzzy bass).
So the idea is to add or subtract "damping material". That is the load that must be accellerated and decellerated at the precise rate to get the notes "low" enough, yet, fast enough too.
When it is right, the depth, resolution and detail can be stunning!!
Amps on the other hand have a quality called "damping ratio". This is a measure of how well the amp can control the speaker driver.
A high number is better in most cases. I think B, is suggesting that the KRELL has a rather high "damping ratio" and because of this, you may not have to remove the full "pea sized" amount of putty I told you to take out.
It is too early to judge now, but it is OK to to have it either way in the begining as the surrounds on the woofers "loosen up" and break in.
After they become "looser", you may want to again reduce the mass of putty just a pinch again to slightly lighten the PR. This will allow it to respond faster to the signal from the amp and since the suspension is now not as resitive, the cone will actually travel further.
If you make it too light, the PR (and even the woofers) will slightly "overshoot" the correct excursion, and you will then "add" just a touch (fingernail full) back.
The symtoms of too much, or too little are the same. Wooly, unclear bass. You want to find that window of clairity, between too much and too little.
Save any putty that you take off in seperately marked envelopes or plastic bags, so that you can add or subtract as needed.
I also notice that you have the woofers "pointed in". At some point, feel free to switch their positions if you want to see what a different bass path and room interaction might sound like.
I think we maximized your "very precise" budget and I think you'll enjoy these more and more, everyday.
You have hours of fun, tweaking and moving them around to find the position(s) that you like the best.
While you could simply leave them as they are, and just allow them to play and enjoy them very much, I think (if I know you) you'll be tweaking and twisting and pinching here and there, and reporting your progress as we go along for the ride.
Have fun
