Got my Krell KSA300s amp - she's a BIG beauty!

[gordonmenninger]

Gordon - Correct the amp is running in pure Class A mode all the way! Yes, i will be calling my granite supplier tomorrow to have a black piece of granite fabricated that I will use as a base for the amp. Do i need to put spikes under the granite or can i just place the granite directly over the berber carpet that is on concrete? Thanks all for the suggestions - yes i will be getting the amp off the carpet in the meantime!

 

[Dan Osib]

Just laying a granite board on the ground then sitting your equipment on it is not enough for proper isolation. You need to somehow drill a hole into each corner of the underside of the granite board then attach spikes there so that it's up in the air away from the ground. Then you should put four sorbothane (rubbery plastic) isolation shoes under each foot of your power amp then sit it on top of the granite. Otherwise you're just wasting your time.

 

[Kenscollick]

Congrats on the new Krell as far as a base I am in agreement with all that you need to get it proper ventilation. My preference under the Base is casters, save your back you will be needing to move it. you can find some cool ones here: http://www.coolcasters.com

 

[TYY]

Have you considered the spikes made by Krell for amplifiers of that vintage? If you are not familiar, the spikes were named Krell Acoustic Mass Dampers and they were screwed into the bottoms of the amplifier feet. The spikes sometimes show up on eBay. However the price can vary significantly.

 

[gordonmenninger]

Just laying a granite board on the ground then sitting your equipment on it is not enough for proper isolation. You need to somehow drill a hole into each corner of the underside of the granite board then attach spikes there so that it's up in the air away from the ground. Then you should put four sorbothane (rubbery plastic) isolation shoes under each foot of your power amp then sit it on top of the granite. Otherwise you're just wasting your time.

Dan, thanks alot for this great idea! So 4 spikes under the granite and then isolation shoes between amp and granite, correct? Do you have any brand recommendation on spikes and isolation? In other words you are saying that the amount of space between the amp and the bottom of the factory feet is not adequate and needs to be increased? It would not surprise me as it feels like a space heater is on when i stand above it! Are there sorbothane feet available that can support 200 lbs??

 

[gordonmenninger]

Dan, thanks alot for this great idea! So 4 spikes under the granite and then isolation shoes between amp and granite, correct? Do you have any brand recommendation on spikes and isolation? In other words you are saying that the amount of space between the amp and the bottom of the factory feet is not adequate and needs to be increased? It would not surprise me as it feels like a space heater is on when i stand above it! Are there sorbothane feet available that can support 200 lbs??

Dan, would the Vibrapods work ok in your opinion? It would seem that if I put these on the feet under the amp it would become very wobbly and unstable? any thoughts?

 

[Gordon Gray]

Gordon,

I've played with different products and they all have a different sonic signature. Sorry, I can hear the groan but, in my experience, it's true.

I do agree with Dan. Spikes / cones on bottom side of platform into the floor and something between the amp bottom and the platform.

I like the Mapleshade brass cones and you can get them on a money back basis. Music Direct also sells a variety of products that you can return for a full refund.

It's an area where you should really on your ears to tell you what's best. Assuming your system is of sufficient transparency, and I assume it is, you will clearly hear the differences.

Good luck.

GG

 

[Dan Osib]

Dan, would the Vibrapods work ok in your opinion? It would seem that if I put these on the feet under the amp it would become very wobbly and unstable? any thoughts?

YOU DON'T NEED TO SPEND A FORTUNE. I SUGGEST BASIC ADJUSTABLE 'MONACOR' FLOOR SPIKES FOR THE GRANITE PLATFORM:- http://cgi.ebay.com/Monacor-Black-S...omeAudioHiFi_HiFiSpeakers&hash=item5ae0a0ca8b
DON'T WORRY ABOUT VIBROPODS, JUST MAKE SURE YOU GET SORBOTHANE FEET (PROVEN TO WORK) LIKE IN THE FOLLOWING LINK FOR GOING UNDER THE AMP FEET:- http://cgi.ebay.com/Genuine-Sorboth...771?pt=LH_DefaultDomain_0&hash=item56417b6303 THERE SHOULD ONLY BE A VERY SLIGHT LEFT/RIGHT WOBBLE WHEN THE AMP IS SITTING ON THEM, THEN YOU'LL KNOW THEY ARE THE CORRECT ONES. THEY COME IN DIFFERENT HARDNESS - SOFT, MEDIUM AND HARD.

 

[gordonmenninger]

YOU DON'T NEED TO SPEND A FORTUNE. I SUGGEST BASIC ADJUSTABLE 'MONACOR' FLOOR SPIKES FOR THE GRANITE PLATFORM:- http://cgi.ebay.com/Monacor-Black-S...omeAudioHiFi_HiFiSpeakers&hash=item5ae0a0ca8b
DON'T WORRY ABOUT VIBROPODS, JUST MAKE SURE YOU GET SORBOTHANE FEET (PROVEN TO WORK) LIKE IN THE FOLLOWING LINK FOR GOING UNDER THE AMP FEET:- http://cgi.ebay.com/Genuine-Sorboth...771?pt=LH_DefaultDomain_0&hash=item56417b6303 THERE SHOULD ONLY BE A VERY SLIGHT LEFT/RIGHT WOBBLE WHEN THE AMP IS SITTING ON THEM, THEN YOU'LL KNOW THEY ARE THE CORRECT ONES. THEY COME IN DIFFERENT HARDNESS - SOFT, MEDIUM AND HARD.

Gordon - I could not find the Mapleshade brass cones..
Dan - I went ahead and ordered the Monacor spikes and the Sorbothane feet - the prices were very cheap and they look like decent products! Coming to think of it - my Krell processor / preamp S1200 U is just sitting on my rack with the stock feet. Should I order a set of the Sorbothane feet for it as well or does it not really matter on a preamp?

 

[Dan Osib]

I forgot to say that you need to check with that company on ebay how much weight your krell weighs exactly so that can advise you which are the correct sorbothane feet for your amp.

 

[gordonmenninger]

I forgot to say that you need to check with that company on ebay how much weight your krell weighs exactly so that can advise you which are the correct sorbothane feet for your amp.

They already arrived in the mail today! I told them I had a 200 lb amp I needed these for but never really got a reply back. They look somewhat thin and I am sure the Krell will squish them like pancakes but we will see! I ordered the spikes and am having a granite stand fabricated with a few extra holes for ventilation and predilled holes for spikes. I hope to have it all together in a week when the granite finished!

 

[Dan Osib]

they already arrived in the mail today! I told them i had a 200 lb amp i needed these for but never really got a reply back. They look somewhat thin and i am sure the krell will squish them like pancakes but we will see! I ordered the spikes and am having a granite stand fabricated with a few extra holes for ventilation and predilled holes for spikes. I hope to have it all together in a week when the granite finished!

holy sh1t!! 200 lbs? That's the weight of an american wrestler! Are you sure about that weight? I wouldn't bother with the sorbothane feet then. Looks like you'll just have to rely on isolation through 2 factors instead (i.e. The solid granite board and then the metal spikes attached to it). That should serve adequate.

 

[Gordon Gray]

Weight does not necessarily mean that the amp will be totally immune from vibration caused artifacts.

I'd still experiment with different devices and decide after auditioning.

Remember the hocky pucks.

GG

 

[gordonmenninger]

Gordon, you mean just regular hockey pucks you can buy at dicks sporting goods? I may have to try that when o get my granite slab! Thx for the reminder!

 

[gordonmenninger]

Hockey Pucks...

I am going to go today to buy some Hockey pucks. I read somewhere also that Wal Mart sells some hockey pucks that are a bit softer than the regulation pucks. Would you think that with a 200lb amp I should just get the standard heavy duty ones because the weight of the amp will compress the pucks enough anyway? Also, would it make sense to place the thin sorbothane coasters I purchased between the pucks and the granite for extra isolation?

thanks!:music:

 

[Gordon Gray]

Gordon,

If you have spikes or cones under the amp and then place the tip on top of the hocky puck, you should get some good ventilation on the under side of the amp. I'd go with the standard puck and not use the sorbothane. I personally am not a big fan of sorbo feet.

Again, experiment and you should hear what each does.

GG

 

[gordonmenninger]

Gordon, Dan, thanks again for your contributions. Dan -yes the amp weighs 198 lbs. and it is all dead weight! I am 6'5, 295lbs football player build and I had a hell of a time wrestling that beast into position!
Hockey pucks are hard to find in my town, especially in 95 degree heat! I ended up buying 4 at a "Play it again Sam" used sports gear store for $2 each. They seem very hard but will be perfect in raising the amp up a bit from the granite and aiding in the cooling hopefully. I will take some pictures once I get everything into place!

thanks

 

[Speedskater]

If I wants some pucks, I would just look under the seats at the rink.
Like Gordon said:
They seem very hard but will be perfect in raising the amp up a bit from the granite and aiding in the cooling hopefully.
But if a unit had vibration problems, I don't think that hockey pucks could solve it.
It might take several hundred pounds per puck to get much vibration reduction.
I think that some people use them under floating floors.

p.s. I doubt that the Krell has vibration problems at the sound level that people listen to ML's.
If you want to check, put the unit in question on top of a sub-woofer playing rock music full blast.
Run some string quartet music through the unit and listen in another room (or building) or just record the output.

 

[gordonmenninger]

got the granite base installed for the amp

I picked up the black granite piece I had fabricated by my Granite guy. He cut a 20x24" piece, polished all edges and drilled 4 small holes underneath for the spikes and 4 1.5" holes for air ventilation. I ended up using 4 hockey pucks sandwiched betwen a sorbothane disk that sits on top of the granite. I think this will work really well and it looks fine imo.. The extra clearance on the bottom should aid in ventilation for this "space heater"!

I have attached a few pictures.

 

[Gordon Gray]

Gordon,

Took me a minute to understand the spikes. Those go into the floor and the existing rubber feet on the amp bottom are sitting on the sorbo / puck. Is that correct?

I think your final step, for best performance, is to install four cones that will sit on the underside of the amp. Bypass the rubber amp feet on the bottom completely.

Top to bottom arrangement. Bottom of amp, top of cone, cone point, hocky puck, top of granite, bottom of granite spiked to floor.

Ditch the sorbo if you try what I've recommended above.

Suggest drilling a small hole into the center of the puck for the point end of the cone to seat into securely.

Will gladly send you some cones to try if you wish. No cost. Just need shipping info. PM if you wish to pursue.

It's amazing what can happen when you eliminate vibration induced distortion.

GG