Driver Tolerances

[Russ_L]

Hi guys- I’m just getting started in DIY and have a general question. I’m interested in driver tolerances and consistency unit to unit since I’m planning on building five (identical) speakers for my SACD multichannel / HT listening room. I did a site search on “tolerances” and every thread result had to do with crossover component tolerances; only one had to do with driver tolerances (and at that really consistency).

I downloaded the spec sheets for the three drivers used in the Statement Monitor and none of the specs had a tolerance attached. Is there a certain assumed tolerance for the specs? How are tolerances taken into account in the crossover design?

For instance, looking at the three drivers used in the Statement monitor I see that the Fountek ribbon tweeter has a sensitivity of 95 dB. However, the Tang Band mid-range, and the Dayton woofer have sensitivities of (approximately) 87 dB. Intuitively (I’m only in Chapter 3 of SB201), the tweeter has to be padded down 8 dB. But what if all three drivers are +/- 2 dB, or 3 dB?

And what if the driver(s) specs are different now from than when Curt did the crossover design? Not too concerned, but my concern is x5. Thanks in advance for any replies.

Russ

PS- and again, this site is incredible. Thanks Asi.

[cotdt]

You pretty much have to measure each speaker yourself. It's all the luck of the draw. Some companies, like Seas, have very good consistency though.

[ThomasW]

If this is a real concern plan on buying at least 50% more drivers than called for so you can try and have a matched set.

But before you do this, measure your ears to see how closely they're matched, and of course you'll need to have a room that's completely acoustically symmetrical otherwise most of this is for naught....

[---k---]

And if something is off, usually you can tweak to compensate for it in the crossover. People here can help.