While it seems appealing to have this slip on mute, it rattles against the body of the bass, and the muting effect to too drastic. The notes are too short to have real vibes.

I received as a gift. Wanted to hate it due to all the negative reviews. But it works perfectly for me on both a 5-string and 4-string. Eliminated the need to palm mute for any reggae song or Police song. Middle of the set... no problem. Slip on, play, slip off. I put it right against the bridge and have no intonation issues that matter in a gig setting. I'm sure there's better/different/other mutes as there always are but I like this one for what it does.

I use this to mute the strings behind the bridge on my Jazzmaster. Works like a charm.

Only works on flatter necks. Then it's just not that great.

Using as directed, at the bridge on a Fender P bass, this gadget adds weird harmonics that make the instrument sound 1/2 step out of tune! I double checked the intonation and it's spot on. Surprised this item made it thru QC to the manufacturing stage. Back to the drawing board.

This item does not really work. It does not make good contact with all of the strings and sounds pretty bad.

It goes on and off pretty early, I'll say that for it. Too much dampening tho - need a softer version.

The "Fump" has issues. A. There must be room for it between the bridge and bridge pickup. B. Can only work when there is little to no radius between strings, and C. It will not dampen the strings uniformly. And it is non-adjustable.
Even ay $, I am returning it. On 6 of my 8 basses, it does not function as well as a piece of foam (and doesn't fit). The density required to subtly dampen the sound without killing it doesn't exist. It actually cause buzzing on 2 of my basses that rendered it useless. Sorry, guys.

This thing is super easy to put on and take off. That's the end of the awesomeness though. I still have to retune all four strings when I use it, and that's hard to do because it over-mutes the strings (some more than others) so the tuner doesn't register them very well. The foam and what looks like Velcro aren't even consistently flat inside the muter, so I don't see how eliminating string radius would help at all. To be honest, I got better tone and response from slipping some rolled up gauze under the strings, and didn't have to adjust the strings as much. Kind of upset I wasted $20 on this thing just for the easy slip on and off. Lesson learned I guess.

Im glad that attempts are being made to get "that" sound, but this guy is a fail. Of all the types of foam and doohickeys I've tried, I'm actually liking palm muting with a pick the best. I guess the Fump could be modified to provide less dampening tailored to each string, but ain't no one got time for that.

I mean that literally, probably. I'm going to put it in there so I don't lose it but I doubt it will come out. Maybe one day I'll find a way to use this effectively in a song or modify it to do a better job at what it's trying to do, but as it is it's kinda useless. It doesn't sound anything like a palm mute. It's a shame, their fretwraps are really useful.

It's a neat concept, but I've seen better executed designs. For the price, it may be worth trying out if you are searching for the Jamerson sound.

Sliding this on your strings is slightly faster than placing foam under them, but you do lose some control of placement and customization. I also had to slide this on upside down because the open space allowed the g-string to vibrate considerable more than the other strings creating a vary inconstant tone and effect.

All-in-all, I ended up just putting flat-wounds on another bass and rolling back the treble. If that isn't an option for you, trying one of these might be an acceptable compromise.

Don't get me wrong, I don't hate it but it didn't really deliver what I was looking for.

I bought one of these a year or two ago. Tried it maybe 3 times. If you're looking for a classic muted sound, do not buy this. Get yourself some foam, cut it, and slap it under the bridge...

I had the same problem as the other reviewers. The Fump does not contact all of the strings, so I get a thump on some and others ring out, or just buzz. To me, it looks like it is poorly made and not very well thought out. Definitely not worth the money! I'm going back to my foam strip.

FYI: I play a Fender American Standard, 4 string P Bass.

The idea of the Fump is great - slip it over the strings next to the bridge and bingo, you've got a palm muted sound - almost that of a plucked double bass. Looks classier than a hunk of foam shoved under the strings and quicker to put on and take off. Sadly, the Fump I received did not contact the strings evenly. E and A strings were nicely muted but the D string rang out with essentially no muting and the G string was hit and miss. The 'jaws' of the Fump were simply too far apart to contact all the strings uniformly. There is no provision to adjust the clamping force. Fortunately, the 'jaws' of the Fump are held together with a screw. I disassembled the unit, ground down the area where 'jaws' meet and reassembled. Now it works. (Dremel comes thru for me again) Way overpriced for what it is now. If Fump would build it so the distance between the jaws could be adjusted they'd have a winner.

Sweetwater service, however, was splendid as usual. Pleasant and easy shopping. On time delivery. Sweetwater is the best.

This think is clunky and doesn't do a good job muting the strings evenly. The E string is completely dead while the G string rings out completely unmuted. This is a terrible product and it is ridiculously priced at $20.

I've been looking for a mute I can use and remove on the fly for years. When I saw the Fump, I thought maybe I could finally end my search. To say I'm disappointed is putting it lightly. The mute does not give a nice, fat, thumpy tone like a traditional mute from days past. In fact, it doesn't really give anything useful. I think the problem is that it uses the strings to hold itself up, which reduces vibration to a point where your playing loses musicality. Also, there is NO way to adjust the amount of muting. If you don't like the tone when you first put it on, you'll just have to live with it.

If you're looking for a mute that is easy to use on the fly, this is it. If you want a mute that will sound like a traditional mute, do yourself a favor and buy a sponge to wedge under the strings.