Probably better to just get a copy of the REW file and look at the impulse response, all will be revealed...
Thank you, Dan... I use REW too and like it.
But my point was not to ask about the software but about the measurement hardware.... not that I have any good reason to be confident REW works at those frequencies either.
Just because the chart (or even the developer of REW) says so, doesn't mean it was a legitimate measurement, esp. south of 20 Hz or anywhere besides an inch from the sub-woofer cone!
With DC-coupled amps, we can make a cone flap at 1 Hz.
Ben
Last edited:
Hello Friends, sorry for my long silence.
Let me try to reply to all of you:
a) I haven't any picture of the sub loudspeaker
b) To make the measures I posted, I used a calibrated Behringer ECM8000 mic connected to a MOTU 896 mk3 A/DAC. As the measuring SW tool I used REW 5, last beta with ASIO support.
c) To measure down to 5 Hz, I simply started the sweep at 2Hz.
I took several measures, near field, at 10, 30 and 50 cm, and at my LP, at about 3 m.
Because I also measured the bass (woofers) response of my Martin Logan Sequal II, I can confirm that the fast roll-off at 20Hz is not a measurement mistake, but most probable it is due the embedded ampli having some limitation or an HP protection filter.
The entire assembly is so made that is impossible to test the embedded ampli alone.
Asap I will post the REW5 data file for anyone would give a deep look into.
Regarding the power of the embedded ampli, as declared in the datasheet, 1400W is the peak and 1000W is the RMS.
Regards, Andrea
Let me try to reply to all of you:
a) I haven't any picture of the sub loudspeaker
b) To make the measures I posted, I used a calibrated Behringer ECM8000 mic connected to a MOTU 896 mk3 A/DAC. As the measuring SW tool I used REW 5, last beta with ASIO support.
c) To measure down to 5 Hz, I simply started the sweep at 2Hz.
I took several measures, near field, at 10, 30 and 50 cm, and at my LP, at about 3 m.
Because I also measured the bass (woofers) response of my Martin Logan Sequal II, I can confirm that the fast roll-off at 20Hz is not a measurement mistake, but most probable it is due the embedded ampli having some limitation or an HP protection filter.
The entire assembly is so made that is impossible to test the embedded ampli alone.
Asap I will post the REW5 data file for anyone would give a deep look into.
Regarding the power of the embedded ampli, as declared in the datasheet, 1400W is the peak and 1000W is the RMS.
Regards, Andrea
AndreaT - you seem pretty capable so don't take this as any more than a question.
Just because you can connect the wires to REW and get charts on your screen, doesn't mean it is really measuring with enough truth to be useful. Maybe yes or maybe no.
I'd say the 3m are the most meaningful measurements. is that what you have been posting?
I find 1/12 octave smoothing to be the best compromise. 1/3 is best for vendors.
Ben
Just because you can connect the wires to REW and get charts on your screen, doesn't mean it is really measuring with enough truth to be useful. Maybe yes or maybe no.
I'd say the 3m are the most meaningful measurements. is that what you have been posting?
I find 1/12 octave smoothing to be the best compromise. 1/3 is best for vendors.
Ben
Last edited:
Hi Ben, what I posted (as written alongside the graph) was taken at 50cm.
I posted that because it was the best with a minimum room reflection.
The 3m response was almost the same.
Anyway, as I will have time, I will get back the raw REW data of my LP measuring session and I will post the whole.
See you soon.
Regards, Andrea
I posted that because it was the best with a minimum room reflection.
The 3m response was almost the same.
Anyway, as I will have time, I will get back the raw REW data of my LP measuring session and I will post the whole.
See you soon.
Regards, Andrea
- Status
- Not open for further replies.