Reader Reports on iWOW Plugin: (later reports first)
If you've used the iWOW plugin, let me know what you think of it. (Include your mac model details, iWOW version used, OS version, CPU speed, etc.) Thanks. (As of March 2007 iWoW current version was v1.1.8.)

(added 2/21/2007)
"I've used iWOW for a while on my 2.0GHz MacBook (2GB RAM, 80GB HD, CoreDuo).
(What iWOW version are you running - OS X 10.4.8 I assume?-Mike)
I'm using 1.1.3, haven't bothered upgrading (to later versions). And yes, 10.4.8.
It works really well and turns the somewhat tinny speakers into something close to what you'd get from a full mid-priced component system. This improvement is particularly noticeable when listening to spoken word (podcasts) recorded at lower bit-rates but also true for music played directly from CD. I noticed perhaps 3-4% more CPU usage.
-Adrian M. "

Note: reports below were not using the later versions of the Plugin. (As of Feb. 2007, latest version was Version 1.1.6)

Version 1.1.6 Changes/Fixes
• Will now process audio when the window is closed.
• Reduced processor usage with mode above.
• Error reporting has been enhanced.
• Auto-updating capability.

(In March 2007 they released v1.1.8.)

(added 10/5/2006)
"(regarding Matt's (MacPro) comment from Yesterday, below. Matt said "In this (compact window) mode, there's no fancy transparent sound scope....but it still doesn't drop all the way down to <1%, which I would expect for a static window.) Is not entirely accurate. The compact mode does have two volume meters that remain active so I would expect the window server process to have some extra activity.

I also tested this app out on a G4 AGP mac with a 900MHz CPU upgrade. When the full window is showing and iTunes is running iWoW will eat up almost all available cycles. Minimized it still takes 25% of the CPU. Must be some serious processing going on there.
Christopher C.
Valley Road and Macintosh Support "

But keep in mind that Matt's test results were from a Mac Pro which has two Dual Core CPUs running at 2.66GHz. That's a lot more processing power than a G4/900. But Matt did note that he saw up to 20% CPU usage (WindowServer task) with no audio playing if the iWoW window wasn't in compact mode.

A follow-up from a Mac Pro owner that previously mentioned a 20% CPU Usage (w/o audio playing):

(from 10/4/2006 news page)
"(Matt - a reader said minimizing the window cuts cpu usage to 5-10%. Did you try that?-Mike)
No, I didn't, but it does fix the "problem"! See below for more testing...

(BTW - what was the CPU usage when it was running/playing music?-Mike)
On my Mac Pro (Quad 2.66GHz, 2GB RAM), I don't see much of an impact on iTunes CPU usage when playing music with iWoW versus without. It maybe adds a percent or two. iTunes sits around 3-6% when playing typically. This is with the iWoW window hidden. Here's a summary:

iTunes CPU usage
================

Idle, no iWoW window showing: ~ 0.6%

Playing, no iWoW window showing: ~ 3-6%

Idle, iWow window showing: ~ 5% and +20% on the WindowServer process

Playing, iWow window showing: ~ 11% and +20% on the WindowServer process

Idle, iWoW window showing, compact: ~ 4% and +4% on the WindowServer process

Playing, iWoW window showing, compact: ~ 8% and +4% on the WindowServer process

The "compact" mode is toggled with the (+) maximize window control in the iWoW window. In this mode, there's no fancy transparent sound scope. As you can see it drops the CPU load down, but it still doesn't drop all the way down to <1%, which I would expect for a static window. With my average 10-ish windows for work, the WindowServer still typically sits around 1% when I'm not interacting with anything. But, as you can see, it's definitely all in the GUI code. The sound processing doesn't add anything substantial, which is pretty nice.
-Matt H."

(from 10/2/2006 news page)
"Hi Mike, I noticed a residual 20% CPU usage on my Mac Pro this morning when nothing was really running. The WindowServer task was the culprit, although I eventually pinned it down to SRS's iWoW plugin for iTunes that you mentioned last week. (Due to the price I passed on it, but there was a reader's comments on it here last week.-Mike)
Closing the iWoW window calmed WindowServer down. Opening it back up again sent it right back to the 20% usage level again. This hit happens *without* any music playing.
I got a kick out of the plugin, but with the price and this hit, I had to uninstall it.
-Matt "

Another reader replied with a note on minimizing the window:

" concerning SRS iWOW: to lower the CPU usage (even with music playing) from 15 - 20 % to a normal 5 - 10 % simply minimize the plugin window to the dock. (Not sure what mac he has-Mike) Hope this can help unsatisfied users; i'm testing it in demo mode.
Ciao, Sam "

(from 9/27/2006 news page)
"iWOW comes to Macs. I already bought 2 licenses. Fabulous is the word! I tried iWOW with my hifi via AirTunes, on my Al PowerBook (tiny speakers) and even on the mac mini (VERY tiny speaker), and in all three instances, the difference is noticable, mostly so on the laptop - I would even say "overwhelming"! Worth every penny, and makes iTunes' equaliser really superfluous...
Best regards, Sebastian
(reader who did a recent Core2 Duo CPU Swap in Mac Mini) "

They have a free trial available, but IMHO the $19.99 price seemed steep. Many years ago I bought a (cheaply made, primarily for gaming IIRC) external SRS device for not much more than that.