SMS-1 v2.1.3 firmware update

[Warpdrv]

Looks like something is coming here....

http://www.avsforum.com/avs-vb/showthread.php?t=942314

I guess we'll have to see how that pans out...

[Warpdrv]

Well Curt already sent me the software, but I don't have the USB to RS-232 cable yet... so I can't install the software...

Subwoofer Management System (SMS-1) Release 2.1.3

Release Notes

This document discusses the latest release of Velodyne’s Subwoofer Management System (SMS) firmware – release 2.1.3. This firmware addresses two issues related to the low frequency management of the SMS. First, it allows the subsonic filter to be set low enough that the only remaining rolloff in the low frequency is restricted only by the hardware, and secondly, corrects some distortion that previous versions of the firmware introduced to the audio spectrum.



Figure 1: SMS-1 Frequency Response

Please refer to Figure one. This graph shows actual output from the SMS-1 with the subsonic filter set to 5 Hz. The various curves shown reflect the subsonic filter as set to 6, 12, 18, 24, and 30 dB/octave -- the steeper the slope, the higher the subsonic slope setting. As you can see, the actual point at which the curves converge is 5 Hz, and at 5 Hz, the audio frequency is down about 5 dB. The typical 3 dB down point is about 8 Hz. This point is a limitation in the hardware and the low frequency response of the SMS cannot be extended any further without changing components in the hardware. In release 2.1.3 the subsonic filter can be set as low as 1 Hz., but any setting below 5 Hz. has negligible effect on the frequency response.

Note that the low-pass crossover in this example is set to the default of 80 Hz and 24 dB/octave.

Some users of the SMS measured the low frequency performance and discovered that the SMS was adding some distortion to the lowest frequencies. Most users did not notice this added distortion due to the low frequencies affected. The distortion was inadvertently introduced as the frequency processing software, which was based on Digital Drive subwoofers, was rewritten for the SMS. The 2.1.3 firmware corrects this problem.

There was some confusion that this distortion was also present in the DD series. This is not and was never true – the distortion was introduced in the SMS only, and has now been remedied.

If you have any questions on this information, please contact Velodyne customer service at techhelp@velodyne.com.

[Sonnie]

This should make SMS owner much happier.

[mike c]

ha, we have the same problem warpdrv!

i wish the sms-1's had USB ports!


purchasing cable now ... it's 3 bucks over here

will post again with before and after pics

[mike c]

bought me the USB to Serial cable: make sure to use COM6 port on the settings.

if the display on the SMS-1 is not flashing, it's not updating

Axiom EP500 - should be good to 18hz

measurements taken 2-3" from the driver
v2.1 lowest possible subsonic filter

v2.1.3 lowest possible subsonic filter


curious why there's barely any difference, I remembered the driver might not be producing anything below tuning

measurements taken from the port
v2.1 lowest possible subsonic filter

v2.1.3 lowest possible subsonic filter


tiny amount of difference
im pretty sure the mic calibration and sms-1 EQ output is fine because when I use the SMS-1 to output its EQ to the receiver, the DD subwoofer is outputting and measured at 15hz

[brucek]

tiny amount of difference

Why not simply measure the SMS response with REW?

Measure a loopback cable with REW first to ensure a flat response and then insert the SMS in the loop and measure...........

brucek

[mike c]

let me add the link so it'd be easier for people here:
http://www.velodyne.com/support/soft...x?sid=454d756r

bruce, im thinking it was a sub from the start which is why no difference was noted.
haven't had time to go into the HT though to retest with another subwoofer.

[mike c]

AVTALK has tested the new software. i don't know the rules re: linking to another forum, so I will just paste the pics instead of the thread link

before:

after:


looks like it's flat to 10hz f3

[håkan]

old firmware vs new firmware
first pic the new firmware 2.1.3
second pic firmware 2.1.2