Jump to content


Please note: You can easily log in to MPN using your Facebook account!

Roland KC-350 --- Blown Tweeter?


jimw

Recommended Posts

My Roland KC-350 keyboard amp is distorting when I play higher notes. It's not real loud distortion, but loud enough to be annoying (to me at least). :confused:

 

Does anyone else have this problem with a Roland amp? It's not under warranty, so I'm hoping to fix it myself. I'm thinking about replacing the tweeter, but wanted to check here first to see if this is a common problem with these amps --- Thanks!

Link to comment
Share on other sites



  • Replies 32
  • Created
  • Last Reply

Has it always distorted like this?

 

Did something happen that may have caused damage to the tweeter?

 

Have you tried playing another instrument through the speaker, perhaps music from a CD? If so, does it still distort?

 

If you are sure the tweeter is the culprit, I'd probably get an exact replacement from Roland.

"Music expresses that which cannot be put into words and that which cannot remain silent." - Victor Hugo
Link to comment
Share on other sites

If you had a pair of them, you could swap out the tweeter from the other unit and see if the problem goes away. Other than that if everything else sounds OK, you probably would be OK in ordering a tweeter. It shouldn't cost that much. Ordering one from Roland is a smart move.
Link to comment
Share on other sites

Originally posted by Is There Gas in the Car?:

Has it always distorted like this?

No, I just noticed it. For awhile I kept blaming it on dirty pots in my volume pedal. But I think I've ruled that out.

Originally posted by Is There Gas in the Car?:

Did something happen that may have caused damage to the tweeter?

No, not that I'm aware of.

Originally posted by Is There Gas in the Car?:

Have you tried playing another instrument through the speaker, perhaps music from a CD? If so, does it still distort?

Yeah, both keyboards have the same distortion. Although that's a good idea to try a CD and bypass everything else. I guess I was looking for an easy answer... an avoid replacing the tweeter :)
Link to comment
Share on other sites

Originally posted by Bobsk8:

If you had a pair of them, you could swap out the tweeter from the other unit and see if the problem goes away.

I wish I did have two, I've always wanted to run stereo. But hearing all the comments here about JBL Eon's and in-ear monitors, I wish I had the money to upgrade to one of those...
Link to comment
Share on other sites

Originally posted by jimw:

My Roland KC-350 keyboard amp is distorting when I play higher notes. It's not real loud distortion, but loud enough to be annoying (to me at least). :confused:

 

Does anyone else have this problem with a Roland amp? It's not under warranty, so I'm hoping to fix it myself. I'm thinking about replacing the tweeter, but wanted to check here first to see if this is a common problem with these amps --- Thanks!

It might not be the tweeter - you might also be overdriving the front end. Try cutting the volume on your synth a bit and upping the master volume to get back to the same volume level and see if its still there.
Link to comment
Share on other sites

Three good posts in a row. :thu:

 

If it were me, I'd take the front grill off, pull the tweeter, and listen. If, after the tweeter is out of the cabinet, you still hear the distortion, it could be cracked, mounted loosely in the cabinet, or otherwise damaged.

 

Since you said that nothing catastrophic happened to blow the tweeter, it could be loose or it could be cracked.

 

Tweeters usually die a sudden death. Either they work or they don't. The voice coil overheats and, like a fuse, the wire disintegrates.

 

The voice coil inside a woofer may just char, but a tweeter usually works... or doesn't.

 

Don't ask me how I know this. OK, I'll come clean - I used to own a pair of Larger Advent speakers. I blew tweeters all the time because the way the crossover was designed, the tweeter handled a lot of lower frequencies (and the woofer handled a lot of higher frequencies - it was a 10 inch woofer, I believe). Using the Advents for patio parties in college, driven with a 60 watt per channnel Pioneer integrated amp... :rolleyes: well, you get the picture.

 

Those Advent speakers were good in their day. However, the woofer surround on all of them would eventually dry rot.

 

Yes, that was the late seventies.

 

Yes, I am an old fart. :rolleyes:

"Music expresses that which cannot be put into words and that which cannot remain silent." - Victor Hugo
Link to comment
Share on other sites

Originally posted by cd1981:

Originally posted by Is There Gas in the Car?:

Don't ask me how I know this. OK, I'll come clean -

Wow Gas, you're really difficult to convince huh? :)
:D

 

Yeah. :rolleyes:

 

 

Well, the truth is that quite a few people owned The Large Advent speaker back in the seventies. (I write that in caps because that's what it was called; The Large... and The Small...)

 

http://image.i-soldit.com/images/0145/101450010438/101450010438_02_01.jpg

 

I figure that there are other folks here who bought those speakers, used them to play DJ at a college patio party, and destroyed the tweeters.

 

Ummmmmmm, it could happen. :rolleyes::P

"Music expresses that which cannot be put into words and that which cannot remain silent." - Victor Hugo
Link to comment
Share on other sites

Originally posted by ProfD:

Gas, do those speakers have the angled pole mount underneath or some contraption on the back? :D:cool:

I know. :rolleyes:

 

Funny - when you're in college, your buds are throwing a keg party, you've got a great-sounding stereo system that you believe is invincible... and you don't know any better -

 

well, that about says it all. Now doesn't it? :freak::D

"Music expresses that which cannot be put into words and that which cannot remain silent." - Victor Hugo
Link to comment
Share on other sites

Originally posted by raddtunes:

The tweeters in the KC amps (I own two) are definitely the weak link in an otherwise fine amp. I've blown + replaced three tweeters, and I play mellow stuff.

OK, I believe you!

regards,

 

--kwgm

Link to comment
Share on other sites

Originally posted by Is There Gas in the Car?:

Three good posts in a row.

:thu:

 

Thanks for all the suggestions!

 

I did manage to find the time to pull the tweeter out; the screws weren't loose, and I didn't see any cracks. When I get a chance I'm gonna hook up my keyboards to see if I get the same distortion with the horn out.

Link to comment
Share on other sites

Originally posted by raddtunes:

The tweeters in the KC amps (I own two) are definitely the weak link in an otherwise fine amp. I've blown + replaced three tweeters, and I play mellow stuff.

Did they quit working completely? Or, were you getting a distorted sound?
Link to comment
Share on other sites

Originally posted by colourisred:

the tweeter in KC 350 by far is the weakest part in this amp. If you replace it with let's say p.ex. a suitable Beyma tweeter (about 70 bucks), you'll be happy that this part conked out.

I wonder what the impedance and power handling spec of the OE driver is so that one can see if a upgraded tweeter will match the specs...? Without that I would be hesitant to just switch drivers.
Link to comment
Share on other sites

Well... it's fixed! :cool:

 

It wasn't a blown tweeter after all. Once I had the tweeter out of the cabinet, I decided to remove the plastic horn part of the tweeter to check out the diaphragm. The diaphragm was intact, but there was some debris around it, including a small piece of straw (the organic kind - not the drinking kind), which was apparently vibrating at certain higher frequencies. After I put it all back together, the "distortion" was gone.

 

I have no idea how a piece of straw got in there (I don't remember playing any barn gigs :D ), but I do use an amp stand which tilts my amp back pretty far. This would tend to funnel any dirt right down the horn.

Link to comment
Share on other sites

Originally posted by jimw:

It wasn't a blown tweeter after all. Once I had the tweeter out of the cabinet, I decided to remove the plastic horn part of the tweeter to check out the diaphragm. The diaphragm was intact, but there was some debris around it, including a small piece of straw (the organic kind - not the drinking kind), which was apparently vibrating at certain higher frequencies. After I put it all back together, the "distortion" was gone.

LOL... never heard that one before. :thu:
Link to comment
Share on other sites

Originally posted by jimw:

I have no idea how a piece of straw got in there (I don't remember playing any barn gigs :D )...

This is quite common, really.

 

And although the sheep may enjoy your music, that straw can really play havoc among the cracks and crevices.

 

As you've determined, the equipment doesn't fare too well either. :freak:;)

"Music expresses that which cannot be put into words and that which cannot remain silent." - Victor Hugo
Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...