New Sub - Please take a look at the spl's (1 Viewer)

[Dom H]

MJ Acoustics Pro 50
Denon 3802
Room aprox 13'x12'
Link Removed
I am thrilled with the British Pro50, okay it's small (8" 50watt sssh!) but it's very tight and has superb transient response. The thing is the readings are a little confusing, why am I not getting a sharp rolloff ~25Hz?
Any comments on the readings and any extra thoughts on reducing the hump around 60Hz (I think they are combining with my mains x-overed at 80Hz) altering the phase has reduced it slightly.
Dom.

 

[Chris Tsutsui]

The folder is empty, I don't see a file with the name "pro50".

 

[Sebastian]

Yep, it is empty, could not find file either.

OT:
Chris did you get my PM?

 

[Dom H]

Fixed

 

[Chris Tsutsui]

I'll check now

 

[James Bergeron]

Not bad, fairly flat, seems a little low though. You could probably EQ that hump. I'm having a hard time to believe that 8" sub goes that low (16hz) your probably hearing harmonics right up to 25hz or so. You have a small room which helps you out.

You may want to actually run the tests at 0 or -10db, -30 is a little low to give actual readings in my opinion.

 

[Tom Vodhanel]

If the room is fairly sealed...no large openings to other areas...rom gain will start in the mid 40s. Adding (in theory)12dB/octave. In the real world...figure 9dB/octave max. But that is still 9dB by 22hz and about 15dB by 16hz.

If you can measure the subwoofer outside(50-60ft from the nearest reflective boundary) this will give you an easy way to find out what the room is adding to the low freqs.

TV

 

[Dom H]

I have updated the file for my usual listening level -10dB (if my amp is callibrated to dolby 105dB, what volume will a cd of tones be with the volume at -10dB, 95dB?)
What is going on, how am I getting a flatish response all the way to 16Hz from an 8' sub with 50 watts?!? The door was rattling like crazy at 16Hz!
here is the sub MJ Acoustics Pro 50

 

[James Bergeron]

Dom, did you hear the 16Hz? Or did the room just feel like a huge pressure chamber?

 

[Dom H]

No I couldn't hear it only feel it. The door would vibrate at 16 & 18Hz.

 

[James Bergeron]

Well sounds like you have a very good sub, I think your sub is helping out. Seems almost impossible though.

 

[Jack Gilvey]

I'm somewhat skeptical of the ability of an 8" driver and 50 watts to produce much useable output @ 20Hz and below.

 

[Dom H]

I have repeated the test at least half a dozen times all with similar results. I also have double checked the RS spl meter corretion values.

 

[Jack Gilvey]

Cool. How have you accounted for THD?