Hi all,
I've lurked in the forum but this is my first time posting. I searched around for info on this stuff but didn't find anything - if there's something I've missed, please let me know.
I'm in the process of modding my Zu Omen Dirty Weekends mkII. I've braced the cabinet near the drivers with dowels and will eventually upgrade the drivers with the Zu 103s and the tweeters with some Radian 475s. I've seen some folks recommend coating the inside of the cabinets with something like Acoust X. I was curious if that delivers a noticeable change. There's already foam bricks directly behind the drivers, so I'm not sure if adding a coating of dampening material besides that will make a huge difference. Thoughts?
Thank you.
I've lurked in the forum but this is my first time posting. I searched around for info on this stuff but didn't find anything - if there's something I've missed, please let me know.
I'm in the process of modding my Zu Omen Dirty Weekends mkII. I've braced the cabinet near the drivers with dowels and will eventually upgrade the drivers with the Zu 103s and the tweeters with some Radian 475s. I've seen some folks recommend coating the inside of the cabinets with something like Acoust X. I was curious if that delivers a noticeable change. There's already foam bricks directly behind the drivers, so I'm not sure if adding a coating of dampening material besides that will make a huge difference. Thoughts?
Thank you.
Acoust X is a panel damping compound, so serves a different function to foam, which is present for acoustic damping / absobing internal reflections, eigenmodes etc.
It probably would make a noticable change, since speaking from fallible memory (so under correction) many Zu enclosures use relatively small amounts of panel bracing and as a result panel resonances / colouration forms a part of their characteristic sound. If that is the case with this model, whether damping that (i.e. lowering the panel fudamental frequency & its harmonics) would necessarily be perceived as an improvement is another question though. Zu speakers are not always necessarily what you would call 'accurate' -studio monitors, by and large, they ain't, and are not supposed to be: they're built more with an eye for enjoyment if you happen to like that sort of presentation, which is fair enough. If we take that, for the sake of argument, as being the case, I'd be wary about making too many changes, especially changes that are difficult to reverse, in case you find they were a step away from what you prefer.
If you want an alternative, try to get some self-adhesive bitumen pads. Play some music and either using an accelerometer, or by feeling / listening to the panels, note where the main modes appear to be. Place a piece of the bitumen (it shouldn't take much) where each of those modes occurs and see what you think. While it will be annoying to remove if you don't like the results, it'll be a lot easier than trying to remove several layers of a painted on compound like Acoust X. Assuming you did like the results, you can always add more bitumen pads, or a painted on compound afterward. Keep in mind though that when it comes to panel damping, more isn't always better.
It probably would make a noticable change, since speaking from fallible memory (so under correction) many Zu enclosures use relatively small amounts of panel bracing and as a result panel resonances / colouration forms a part of their characteristic sound. If that is the case with this model, whether damping that (i.e. lowering the panel fudamental frequency & its harmonics) would necessarily be perceived as an improvement is another question though. Zu speakers are not always necessarily what you would call 'accurate' -studio monitors, by and large, they ain't, and are not supposed to be: they're built more with an eye for enjoyment if you happen to like that sort of presentation, which is fair enough. If we take that, for the sake of argument, as being the case, I'd be wary about making too many changes, especially changes that are difficult to reverse, in case you find they were a step away from what you prefer.
If you want an alternative, try to get some self-adhesive bitumen pads. Play some music and either using an accelerometer, or by feeling / listening to the panels, note where the main modes appear to be. Place a piece of the bitumen (it shouldn't take much) where each of those modes occurs and see what you think. While it will be annoying to remove if you don't like the results, it'll be a lot easier than trying to remove several layers of a painted on compound like Acoust X. Assuming you did like the results, you can always add more bitumen pads, or a painted on compound afterward. Keep in mind though that when it comes to panel damping, more isn't always better.
I never liked any Zu speaker i heared (not this one), i think they are muddy and bright. But some seems to like them a lot, altough they are very coloured.
Damping them (by bracing or otherwise) will change the characteristics like Scott said, so i would also suggest to do it in a way you can return to the original state. Acoust X is not what i would suggest, bracing it (in a way you can remove it again) more or use adhesive bitumen is indeed a better id to dampen the panels.
Damping them (by bracing or otherwise) will change the characteristics like Scott said, so i would also suggest to do it in a way you can return to the original state. Acoust X is not what i would suggest, bracing it (in a way you can remove it again) more or use adhesive bitumen is indeed a better id to dampen the panels.
Thanks for that, @scottmoose. That was very helpful. I agree that the best mods are those you can reverse if necessary. I'll look into some bitumen pads. I appreciate the input.
Just circling back on this. I used some 2mm thick butyl rubber - basically DynaMat, the stuff used to deaden sound in automobiles - to coat some of the interior of the Zu cabinets. I left the fronts - the sides with the drivers - naked. Otherwise I applied about 16" of the stuff to the remaining three sides, roughly the top half of each 36" side. I flattened it as best I could using the butt end of a screwdriver as a roller.
As per the sound, I'm still evaluating. I did one speaker first to A/B against the untreated speaker. There is a noticeable difference, but oddly enough, I can't tell if I like it or not. I've done plenty of DIY projects in the past, including mods that improved sonics, mods that messed things up, and those that made no audible difference. This is the first time where I can definitely hear a difference but keep changing my mind as to whether I like it or not.
The butyl rubber seems to have sharpened the audio and made things more dynamic. But it's also punched up the bass to an extent I don't know if I like or is good - sometimes it sounds great, but sometimes it's boomy, especially on the low bass end. I know it sounds weird. It's hard to describe. I'm like, "Is that good dynamic boomy? Or bad dynamic boomy? And is it coloring everything else?"
Generally I'm of the mind that if I don't know whether I like something I should get rid of it. But I can't tell if the problem is with the treatment or just in the way I applied it - did I flatten it enough? Did I put in too much, or not enough? The product I used has a thin aluminum coating on the non-sticky side that I'm wondering is adding unwanted sonics. Questions, questions.
I'm wondering if I need to bring over a neighborhood audio friend to get his diagnosis. If only there were roving professional audiophiles who made house calls.
As per the sound, I'm still evaluating. I did one speaker first to A/B against the untreated speaker. There is a noticeable difference, but oddly enough, I can't tell if I like it or not. I've done plenty of DIY projects in the past, including mods that improved sonics, mods that messed things up, and those that made no audible difference. This is the first time where I can definitely hear a difference but keep changing my mind as to whether I like it or not.
The butyl rubber seems to have sharpened the audio and made things more dynamic. But it's also punched up the bass to an extent I don't know if I like or is good - sometimes it sounds great, but sometimes it's boomy, especially on the low bass end. I know it sounds weird. It's hard to describe. I'm like, "Is that good dynamic boomy? Or bad dynamic boomy? And is it coloring everything else?"
Generally I'm of the mind that if I don't know whether I like something I should get rid of it. But I can't tell if the problem is with the treatment or just in the way I applied it - did I flatten it enough? Did I put in too much, or not enough? The product I used has a thin aluminum coating on the non-sticky side that I'm wondering is adding unwanted sonics. Questions, questions.
I'm wondering if I need to bring over a neighborhood audio friend to get his diagnosis. If only there were roving professional audiophiles who made house calls.