k55m is buzzing, use a diffrent driver?

[6l6gc]

when I first got my pre owned khorns, one k55m was distorting and buzzing,
long story short after triple verifying it is indeed the driver,
I released all its bolts just a bit,
wiggled the top a little bit and cross tightened them back.
most of the problem seems to be gone for music, but it's not %100, whenever I do a sinewave sweep,
that particular k55m will buzz and distort on particular freq. such ~925hz and some others.

Now is an opportunity (or excuse) to have some fun and replace them.
I am using digital active cross over, I can bi or tri amp so this opens up endless possibilities
For mating other drivers.
I use 511b horns, so yet more choices.

I would appreciate anyone opnions pointing me in some direction
as I try to reduce the many choices, I am looking at any of these

1) Selenium d250, quick fix, cheap, will have a hole in the midrange with k77, I can eq to compensate, and I like a reduced mid anyway.
2) pylepro pds772, quick fix, cheap, Titanium, do we believe their claim 500hz-18khz ? no published measurements, anyone used these?
3) peavey rx22, expensive for a "quick fix", 500hz-20khz titanium, published specs.
4) The sane thing to do "do the proper thing", get the atlas k55v and be done with it.(but hey where is the fun?)
5)gpa 902?, now my pocket really hurts, are they worth it?
6) we only live once approach, go all the way and mate k402/k69 with the khorns.( although I could probably do this,
I haven't worked on the guts for that kind of mega expense yet, so for now I will more than likely keep on dreaming? Or will I..)

will the 511b accept a 2" exit driver? should I have a look at those?
Can I go fully 2 way, with 511b horns and a single 500hz-18hz driver on the 511b?
Will covering midrange and tweeter freq from a single driver have increased fm distortion?

I am not looking for audiophile correctness or a straight line freq response

But I am looking for a practical way to get very low distortion striking dynamics and detail.

Thanks for anyone pushing me in some direction.

[djk]

"will the 511b accept a 2" exit driver?"

No. Altec did make a 511E that accepts the 288 large format 1.4" aluminum driver, rare and expensive (the horn, when found).

"Can I go fully 2 way, with 511b horns and a single 500hz-18hz driver on the 511b?"

You could, but I wouldn't. The 511B sounds much better crossed at 650hz/12dB, but that leaves a bit of a hole with the Klipschorn.

"Will covering midrange and tweeter freq from a single driver have increased fm distortion?"

To a certain extent, yes. Distortion in the top octave is proportional to the square of the bandwidth in octaves.

I would send your K55M to forum member BEC for repair, that will give you some breathing room while you decide how much money you want to throw at this project. The K55M may have a problem with the plastic back cover buzzing too. Have you replaced the bananna plugs with spades yet? The first K55M I heard buzzing was actually the banannas.

"Thanks for anyone pushing me in some direction."

From experiences of friends that have gone the 2" route, I would suggest that. A couple of people I know use the TAD 4001, but still use a tweeter. This is a function of both distortion (mentioned above), and dispersion. One fellow replaced his Community M200s with the TAD, and remarked the M200s sounded better in some aspects. Another person tried the BMS and Community, and thought the M200 was better (but requires a 4Khz crossover). Many people have prefered the M200 to JBL 2" drivers, and subsequently sold the JBL.

One person tried the M200, the BMS, and a cone-driven midrange horn. He thought the M200 sounded better than the BMS, but the cone-driven midrange horn as even better (he uses a 1" driver for the tweeter).

I have a bunch of just about everything (Community, Altec, EV, JBL, BMS, RCF, Beyma, Celestion, etc), and most of it has something to recommend it (otherwise I wouldn't have bought it).

[djk]

"In the app. 300-1000 range I have tried two different compression drivers (BMS 4592 ND and Community M200) on two different horns (Jabo KH-50 and Bentwood 200); AND several cone drivers (8" Fane Studie 8M, 5.25" PAudio WN-520N; 8" Ciare 8.50 NDMR; and 6.5" Ciare 6.38 NDMR) all on a conical mid horn with a 81 cm2 throat.

The Community M200 is somewhat more open and clean than the BMS, but I do prefer a cone driver in that range - especially in the low register - they simply sound more natural and less 'squeezed' to me. The best for me so far is the 5.25" PAudio WN-520N. But, this may, at least in part, be due to the horn and not only the driver typology as such. "

PK from AudioAsylum.

[Groomlakearea51]

1) Selenium d250, quick fix, cheap, will have a hole in the midrange with k77, I can eq to compensate, and I like a reduced mid anyway.

The Selenium D250X is "hot" (109 db) and needs a an 8W resistor (in-line) to more or less match. I use them on occasion, and in particular, in lieu of the K55 in Heresy's. To avoid the freq "holes" you should also use Bob's CT-125 tweeters.

If you want to simply not use the M's, Bob also has the Atlas PD5VH's (aka.... the K-55). I personally never liked the "M" and only have one pair in a set of K'horns.

[Bacek]

>one k55m was distorting and buzzing

Somewhere here there is a thread about strange noise from k-55-m. Guy fixed it by regluing back plastic cover.You can check this by touching/pressing back cover while driver is plaing loud. If distortion voids you will know what to blame for that.

[6l6gc]

Somewhere here there is a thread about strange noise from k-55-m. Guy fixed it by regluing back plastic cover.You can check this by touching/pressing back cover while driver is plaing loud. If distortion voids you will know what to blame for that.

Thanks for the tip I will search for the thread,

The distortion actually changes as pressure is applied,

not so much with music, but mostly when sweeping with a sine wave,I will have ago at it when I have some kind of "spare",

for fear I might ruin what I have and end up speakerless. Thanks again.

[Don Richard]

3) peavey rx22, expensive for a "quick fix", 500hz-20khz titanium, published specs.

I cannot rate the others you mentioned, but I am presently using the RX-22. It will not work (for long) crossed @ 500 Hz. That is the lower limit of the driver, which was designed to cross @ 800-1600 Hz. You need to use a driver that goes an octave lower than the crossover point. The K-55's lower limit is 175 Hz.

Yes, you can go 2-way with the 511 horn. I think most folks doing that are using the 902D driver for that application.

[Bacek]

http://forums.klipsch.com/forums/p/72281/709251.aspx#709251