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Author Topic: Quickie and Quicksand spl question  (Read 2025 times)

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Offline aragorn723

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Quickie and Quicksand spl question
« on: May 02, 2015, 02:22:39 PM »
Hi,

How many db could a Quickie/Quicksand combo create with 8 ohm, 92db sensitivity speakers (without distortion).  Thanks,

Dave

Offline Bonzo

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Re: Quickie and Quicksand spl question
« Reply #1 on: May 02, 2015, 11:41:52 PM »
The specs said 4W, 8ohm, 5% distortion, so maybe 2 or 3 W of "clean" power, so let's say a conservative 95 db? (3 db each power doubling after the first watt)
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Offline Bonzo

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Re: Quickie and Quicksand spl question
« Reply #2 on: May 03, 2015, 01:58:15 AM »
And that the value is at 1m.
So subtract 6db each doubling of the distance from the speaker (back to 89db at 2m, 83 at 4m ecc).
And add 1 db because we're speaking about a stereo set (there is a small increase of spl for 2 speakers, but if I remember correctly only when adding another speaker, for 3 speakers spl is the same as 2).

Ciao
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Offline Doc B.

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Re: Quickie and Quicksand spl question
« Reply #3 on: May 03, 2015, 07:01:46 AM »
4w at 5% is a good figure because of the pleasant, even order rich harmonic spectrum of the single ended circuit. Thus more like 96/97 would probably sound fine. Also you are not accounting for the reverberant field when you say sound falls off 6dB with doubling of distance. Anechoic, yes, but not in a real room. Try measuring this with an SPL meter in a typical room and you will see that there is quite a bit of energy present at a distance.
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Offline Bonzo

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Re: Quickie and Quicksand spl question
« Reply #4 on: May 03, 2015, 07:17:58 AM »
Also you are not accounting for the reverberant field when you say sound falls off 6dB with doubling of distance. Anechoic, yes, but not in a real room. Try measuring this with an SPL meter in a typical room and you will see that there is quite a bit of energy present at a distance.

You're right, they are a rough approximation: in real world, and in real room, reverbaration plays a big role in restoring the loss (and adding some colorations too!).
Bisogna avere orecchio!

Offline aragorn723

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Re: Quickie and Quicksand spl question
« Reply #5 on: May 03, 2015, 07:55:25 AM »
Just curious..  I have been thinking about possibly downsizing from a monster solid state amp to something that takes up less room (trying to downsize stuff in the condo to make more room till we can move).  This morning I was listening to some music at a normal volume, and measured it with a smartphone app, and that was around 50db on average.  If there's a really good song, I like to turn it up, and that is around 60db (at ~8 feet away).  The neat thing about the Quicksand would be that changing the amp would take the whole system off the grid too (The Quickie is fed by a battery powered laptop, which also powers the dac).  It sounds like the Quicksand would make enough power for me, but I wonder about the whole impedance thing too (remembering a thread from quite a while ago).  Would this be workable for my situation?

Dave

Offline Paul Birkeland

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Re: Quickie and Quicksand spl question
« Reply #6 on: May 03, 2015, 12:22:59 PM »
but I wonder about the whole impedance thing too (remembering a thread from quite a while ago).  Would this be workable for my situation?
You have 8 Ohm speakers, right???
Paul "PB" Birkeland

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Offline aragorn723

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Re: Quickie and Quicksand spl question
« Reply #7 on: May 03, 2015, 12:30:53 PM »
yes, Definitive Technology BP6Bs