Usefulness of In-Room LF Measurements vs. No Measurements (ref FH)

[sayrum]

Off topic moved http://www.diyaudio.com/forums/full-...-10-3-10p.html


Hello
I would also apreciate measurements (not sims!) of your cabinet creations.

Originally Posted by planet10

... Scott may have some sims (for that matter i might as well), but he is on the road right now. Any room measure likely tells you more about the room, and anechoic measures would not paint a realistic picture.

By gating one can get accurate measurements down to lower mids / upper base even in a larger (living)room...

Regards

[planet10]

Originally Posted by sayrum

By gating one can get accurate measurements down to lower mids / upper base even in a larger (living)room...

The speaker is designed to use the room. And the question is about the difference in the LF.It will be room dependent. Take the room out and the measurement is meaningless.

Catch 22.

dave

[xrk971]

Originally Posted by sayrum

Hello
I would also apreciate measurements (not sims!) of your cabinet creations.


By gating one can get accurate measurements down to lower mids / upper base even in a larger (living)room...

Regards

+1, I agree that a measurement would be useful. I am surprised that after all this time, no one has measured and posted results from the XL. Or maybe I missed it?

[planet10]

Originally Posted by xrk971

+1, I agree that a measurement would be useful.

More likely confusing.

The FHs use variable damping to tune the bass, the design uses the room as part of the design, so any measure is only applicable to the specific build and the room it is in. Take the room out and you are hobbling the speaker. So measures are only useful to the guy tuning it in hid toom

And knowing those that treasure their measures and give them toomuch creed they would take what they see and generalize it well beyond their applicability.

dave

[xrk971]

Originally Posted by planet10

More likely confusing.

The FHs use variable damping to tune the bass, the design uses the room as part of the design, so any measure is only applicable to the specific build and the room it is in. Take the room out and you are hobbling the speaker. So measures are only useful to the guy tuning it in hid toom

And knowing those that treasure their measures and give them toomuch creed they would take what they see and generalize it well beyond their applicability.

dave

I guess we will never see a measurement of an XL - even with room effects that is fine at least it gives a point in the range of possibilities. Just kind of surprised that given how inexpensive and easy it is to have measurement capability that I have never seen a single freq response or distortion plot.

[planet10]

Originally Posted by xrk971

given how ... easy it is to have measurement capability

Easy to provide reults that are more ghost than useful.

When the only tool you have is a hammer, everything starts looking like a nail.

dave

[Bob Brines]

Originally Posted by xrk971

I guess we will never see a measurement of an XL - even with room effects that is fine at least it gives a point in the range of possibilities. Just kind of surprised that given how inexpensive and easy it is to have measurement capability that I have never seen a single freq response or distortion plot.

You seem to have missed Dave point. As I have grown in this hobby, I have come to understand that the on-axis 1 meter response is absolutely worthless when trying to figure out how a speaker will sound in my asymmetrical, poorly treated room with the speakers 2.5m from my chair and the speakers toed out 15*. Yes, I have 0.5m on-axis plots extrapolated to 1w/m on my web site, but that has no bearing on what I hear in my room. The FH3 is a corner horn. Exactly what kind of measurement do you think will be useful in extrapolating to your room?

Bob

[xrk971]

Well if someone wanted an *idea* of the sort of response they can get if they were to build it and if it was placed in a corner in their room at the same distance from the corner, sure it is a useful measurement. The measurement should have the details and caveats of the placement. My question is also about how so many builds and yet not a single measurement.

I guess it comes down to there are two kinds of diy'ers: those who do and those who don't, measure that is. I won't ask anymore in this thread because it seems no one is the least curious what the typical corner placement and xx grams of stuffing in a speaker measurement is. I just want to know where the bass corner is, and how it rolls off for a *typical* 3 ft away from each wall at 45 deg corner placement. Similarly, do we ever listen to a speaker with our ears 0.5m away? No, but that measurement is great for reducing the effect of room modes, and allows a characterization of the cabinet and driver's intrinsic ability.

I appreciate all the measurements that Bob Brines provides and think more people should do the same.

[Ultralight]

Yes, understood but I think somewhere in between would be a good solution - to have SOMETHING measurable to go on beyond, 'Better bass slam than FH Mk3..." For example, one can say, 'In my room of 15 x 20, and 12 inches from back wall, I measured 35hz at 3db down....." Something like that to just at least give a basic sense. If someone says, 30 hz, that will give a different sense if someone says 40 hz.

All speakers, no matter what do interact with the room - perhaps the FH more, but that is still something true of all speakers.

UL

Originally Posted by planet10

More likely confusing.

The FHs use variable damping to tune the bass, the design uses the room as part of the design, so any measure is only applicable to the specific build and the room it is in. Take the room out and you are hobbling the speaker. So measures are only useful to the guy tuning it in hid toom

And knowing those that treasure their measures and give them toomuch creed they would take what they see and generalize it well beyond their applicability.

dave

[xrk971]

Originally Posted by Ultralight

Yes, understood but I think somewhere in between would be a good solution - to have SOMETHING measurable to go on beyond, 'Better bass slam than FH Mk3..." For example, one can say, 'In my room of 15 x 20, and 12 inches from back wall, I measured 35hz at 3db down....." Something like that to just at least give a basic sense. If someone says, 30 hz, that will give a different sense if someone says 40 hz.

All speakers, no matter what do interact with the room - perhaps the FH more, but that is still something true of all speakers.

UL

+1 exactly the thing we need. The paucity of data is just puzzling to me.