[brother love]

My GR Research N3 transmission line speakers are installed on wood floor with standard block perimeter foundation/ wood floor joists/ plywood sub-flooring. I added DIY plinths to get tweeters to ear level from my nearfield chair listening position.



Conventional wisdom is that I should decouple/ isolate these ~ 70# speakers from live floor conditions vs. my current spike arrangement.

Since my last 4 speaker purchases have been Danny's products (X-LS monitors, sealed servo sub, N2x's, N3's), I thought I would get informed info from fellow GR Research owners. What have you used that works for you? (brownie points given for economical/ DIY since I am a cheap bastard  ).

In the process of researching previous AC threads, IsoAcoustic stands, etc.. I came across this excellent article by Ethan Winer: Testing Loudspeaker Isolation Products. Quite enlightening!

http://ethanwiner.com/speaker_isolation.htm
 

[gab]

I like this Ethan Winer primer 

http://exposed.ethanwiner.com/ate.htm

[Roninaudio]

Good article....(From OP)

[Speedskater]

Now that some cell-phones have accelerometers, an audiophile can now measure the effectiveness of different isolation devices. 

[Wind Chaser]

Smart - few people give a second thought, much less any consideration to the height of their speakers,
especially if they are floor standers. 

I designed my own risers and built them to spec. In addition to providing the right amount of "lift" they
also act as isolation platforms. The interior of each platform contains three layers of foam of varying
densities so none of the wood (MDF) actually touches the ground.

[DaveC113]

I get great results from IsoAcoustic stands.

Results do depend on the floor and home construction for sure, but for me, I got a subwoofer stand to try out years ago. I crank up my system, the result was subjectively cleaner bass, but also much less resonance throughout my home. All the things that normally rattle around stopped or were reduced in amplitude by a large amount. My home was "singing along" with the music a lot less. Picture frames, lighting enclosures, windows, etc. all vibrate less or not at all anymore.

Later, I tried them under my 15" woofer enclosures and the results were even better... less smearing of the midrange, which results in better imaging and soundstaging. These 15s can rattle my house much more than my sub could and the result here was even better as far as reduced resonance in my home. 

The thought that speaker cabs don't vibrate enough to transmit vibration to the floor is one of the most ridiculous things I've ever heard.

[rollo]

   We prefer rollers. Similar principle to that of" Roller Blocks" or "Pone Tunes". Try using a 7/8' th. wood dowel cut to speaker width plus one ft. Place dowels front and rear so dowel is at a right angle to speaker enclosure. Your done.
  The cone moves so the natural movement of a non fixed speaker just sounds VG to us. Try it.


charles

[wushuliu]

Oh, that Ethan...

[gaelen5]

I like this Ethan Winer primer 

http://exposed.ethanwiner.com/ate.htm

That's easily one of most messed up video I've seen on the internet, and I've seen some pretty weird shit.

I can't tell if this guy is a total clown, or if he's just stuck in the 80s? He doesn't seem to have done any recent research, and makes claims like cables make no difference. http://ethanwiner.com/myths.html

[brother love]

Thanks for the great input so far!  Rollo, I am going to try that dowel method for sure (talk about cheap & cheerful).

Yes, that Ethan Winer (the man loves portraits w/ his cats).   

Agree with him or not, he was a great source for acoustic treatment info: http://realtraps.com/info.htm

[poseidonsvoice]

I get great results from IsoAcoustic stands.

Results do depend on the floor and home construction for sure, but for me, I got a subwoofer stand to try out years ago. I crank up my system, the result was subjectively cleaner bass, but also much less resonance throughout my home. All the things that normally rattle around stopped or were reduced in amplitude by a large amount. My home was "singing along" with the music a lot less. Picture frames, lighting enclosures, windows, etc. all vibrate less or not at all anymore.

Later, I tried them under my 15" woofer enclosures and the results were even better... less smearing of the midrange, which results in better imaging and soundstaging. These 15s can rattle my house much more than my sub could and the result here was even better as far as reduced resonance in my home. 

The thought that speaker cabs don't vibrate enough to transmit vibration to the floor is one of the most ridiculous things I've ever heard.

Ok, let's not be too rough on Ethan, he does give very good acoustic advice, although his universal approach to side wall 1st reflections I will disagree with (He only agrees with absorption in that area, nothing else!).

What is wrong with Ethan's testing in my opinion is not that measurements don't matter, it's that the wrong measurement was used in this case to arrive at his conclusions. So the problem here is the testing modality.

That being said, my experience with Isoacoustics stands coincides with DaveC's results and yes, it is subjective. The type of testing to properly test isolation products from my understanding is quite expensive, in other words, you can't just use REW and see if there is a change in frequency response 

In addition, I would like some psychoacoustic research thrown in. I have been tested with blindfolds listening two of the same type of speaker (it was a coax!) with height corrected and I was able to tell which one had an Isoacoustics stand and which one didn't. That being said, I would love for a testing modality to prove it so I can sleep well at night. Yes, I'm still unsure!

Another isolation method type to try is what PrimeAcoustic does with their RX7 monitor isolations (Recoil stabilizer: http://www.primacoustic.com/recoils/). An avid DIY'er could come up with something similar like using a granite slab with foam like product on it (NoRez, PartsExpress Sonic Barrier, etc...)

Best,
Anand.

[Danny Richie]

Some of the terminology is a little messed up in regards to coupling, de-coupling, and isolation.

What most of these devices really do is damp out vibration. These products act like a shock absorber on your car, but your car is not de-coupled from the road. The tires are still on the road. And the speakers are still coupled to the floor.

Rule of thumb is if the floor can move then there can be some benefit from adding a damper. But if the floor is a solid concrete floor then couple the speaker to the floor with floor spikes.

[Dieterle Tool]

Thanks for the link and string brother love.

And I have no experience with Ethan Winer, but that second video is pure gold. I will be seeking an ecdysiast for all my isolation and cabling recommendations from now on. 

-Dieter

[brother love]

... my experience with Isoacoustics stands coincides with DaveC's results and yes, it is subjective. The type of testing to properly test isolation products from my understanding is quite expensive, in other words, you can't just use REW and see if there is a change in frequency response 

In addition, I would like some psychoacoustic research thrown in. I have been tested with blindfolds listening two of the same type of speaker (it was a coax!) with height corrected and I was able to tell which one had an Isoacoustics stand and which one didn't. That being said, I would love for a testing modality to prove it so I can sleep well at night. Yes, I'm still unsure!

Another isolation method type to try is what PrimeAcoustic does with their RX7 monitor isolations (Recoil stabilizer: http://www.primacoustic.com/recoils/). An avid DIY'er could come up with something similar like using a granite slab with foam like product on it (NoRez, PartsExpress Sonic Barrier, etc...)

Best,
Anand.

Thanks Anand for the excellent info!  That makes 3 AC'ers that like the IsoAcoustic stands (Dave & corndog71 being the other 2).   I had looked into the PrimeAcoustic RX7 & ruled out due to higher price, but DIY version would be feasible (albeit a lot of effort).

[brother love]

Some of the terminology is a little messed up in regards to coupling, de-coupling, and isolation.

What most of these devices really do is damp out vibration. These products act like a shock absorber on your car, but your car is not de-coupled from the road. The tires are still on the road. And the speakers are still coupled to the floor.

Rule of thumb is if the floor can move then there can be some benefit from adding a damper. But if the floor is a solid concrete floor then couple the speaker to the floor with floor spikes.

Thanks Danny. Nomenclature aside, have you used anything that you recommend to dampen vibrations for your speakers on live wood floors? My wife was raised in Texas & still has family there, so I know that most houses are on concrete slabs, but with older ones being pier & beam. Anand mentioned No Rez as a possible effective layer & I know that you sell it for speaker linings. Have you ever tried it under speakers?

[Wind Chaser]

Rule of thumb is if the floor can move then there can be some benefit from adding a damper. But if the floor is a solid concrete floor then couple the speaker to the floor with floor spikes.

My listening room is in the basement, so I'm pretty sure there is a concrete floor under the carpet. As stated above, my risers (5.15" high) also act as isolation platforms.  The top 2" layers are solid MDF and everything below on the inside is foam of varying densities. Despite the concrete floor, these do a tremendous job of really cleaning up the bass - and the mids too. The difference is pretty obvious spectacular as tweaks go.

I hate spikes. Besides damaging the carpet they make fine tuning a pain. I'm much happier being able to slide my speakers around without snagging the carpet. 

[DaveC113]

My listening room is in the basement, so I'm pretty sure there is a concrete floor under the carpet. As stated above, my risers (5.15" high) also act as isolation platforms.  The top 2" layers are solid MDF and everything below on the inside is foam of varying densities. Despite the concrete floor, these do a tremendous job of really cleaning up the bass - and the mids too. The difference is pretty obvious spectacular as tweaks go.

I hate spikes. Besides damaging the carpet they make fine tuning a pain. I'm much happier being able to slide my speakers around without snagging the carpet. 

I agree. I've never found spiking a speaker to be better vs isolation. Concrete floors resonate too, and it doesn't sound good.

[Wind Chaser]

That remind me, I tried both spikes and isolation under a sub in that same room. No contest, isolation all the way! 

[DaveC113]

One of my friends tried hanging his speakers, but then you'd have to get all OCD about what kind of rope! 

[Danny Richie]

The effectiveness of a damper, or what some of you are calling isolation, varies greatly depending on the resonance range or resonance frequency of the floor. There is a trade off between damping a resonance and stabilizing the speaker. So there is no one size fits all solution.

Imagine your speakers to be a boat on the water. You want to average out the little ripples to keep the boat stable. But if the big waves are rocking the boat then you have a whole different issue to address. If the waves are too big then you have to anchor it to the bottom like the dock.

So ideally you want to couple the speaker to floor to keep it from moving forward and back while damping out the smaller vibrations that the floor is creating.

And hanging or suspending a speaker can be good for high frequency, but really bad for lower frequency ranges. It can really knock the bass out of it.