K-43 Abuse

[DrWho]

You forgot the part about cheap price and the fact that some of this technology is undertsood better such that they can get by with cheaper stuff. It's not great, but it gets the job done.

[Duke Spinner]

.think of any EQ boost as reducing the peak output of the system. So if the lascala can do 120dB and you add 12dB of EQ, then don't go above 108dB. You'll always be safe using this approach.

Who ...I'm familiar with the concept of reducing the Ultimate dB output , by the amount of EQ ...

but i wonder if i'm gonna be chasin' my A$$ tryin' to get decent 40 hz performance from that small horn ...??

anyway's ...

i'm sure they're gonna produce an awesome 150 hz thump ....

[djk]

The K43 will break when a bunch of EQ is used to extend the low end for PA use. The suspension will reach its limits at first, and nothing will go bang. After a while the apex of the cone will get mushy where the voice coil pushes on it during its forward stroke. Then on a rear-ward stroke the coil will rip clear off the cone. Time for a re-cone.

If you need some serious low end output, you need a sub.

As regards amplifiers made in China:

The QSC RMX series is one.

The Behringer EP series is one.

The Tapco J series is another.

All have the IDENTICAL schematics, they even have the IDENTICAL reference number scheme for the resistors, capacitors, transistors, etc.

The QSC RMX series is much better than the made in USA MX series it replaced. The schematic is identical, with the addition of an extra pair of outputs, and more heatsink too.

Behringer uses a slightly smaller transformer.

Tapco uses a much larger transformer, and is the only one rated 20hz~20Khz at 2 ohms with both channels driven.

Don't think of running any at 2 ohms, you can buy two Behringer EP2500 for the cost of one QSC RMX2450 and run them at 4 ohms. The Tapco J-2500 with its larger transformer is only about $70 more than the Behringer.

The Alto, Peaver PV series, and the soon to be discontinued (AFAIK) Crest CPX series look to be very similar as well. The Peavey and Crest have a 24dB crossover for sub use at no extra cost, or rack space.

On an interesting note, although the scematics may be identical, they all seem to use a different board layout.

[Duke Spinner]

.

If you need some serious low end output, you need a sub.

well, no ...Dennis

for low end i have them scoops, actually, they dont go that low anyways, bein scoops

i don't need much below 50 hz anyways.....

as it only makes the stage boom and feedback

[djk]

"for low end i have them scoops, actually, they dont go that low anyways, bein scoops"

I don't mind the JBL4520s, they have good output down to low 'E' (42hz).

I like my PA to go to low 'B' (31hz) for live music, although 40hz is OK for 99% of all material.

For music at home I like to go to 27hz.

Most systems that go lower than this have so much distortion at loud volumes that the FM (loudness) effect kicks in, and what 'sounds' like 15hz is actually the third harmonic (45hz). Tom Danley is hip to this and gives some numbers at AA and elsewhere.

[Mr. Widget]

.think of

any EQ boost as reducing the peak output of the system. So if the

lascala can do 120dB and you add 12dB of EQ, then don't go above 108dB.

You'll always be safe using this approach.

Who ...I'm familiar with the concept of reducing the Ultimate dB output , by the amount of EQ ...

but i wonder if i'm gonna be chasin' my A$$ tryin' to get decent 40 hz performance from that small horn ...??

I think you will... I bought a pair of La Scalas a few years back that had

been used at a pro sound rental company... the woofers were not only

blown, the top two layers of plywood on the "motor board" were burnt

completely away... gone! They had cranked up the bass with a big amp

and started a pretty good fire... the repair work to bring them back to

spec wasn't trivial.

Use caution and you should be fine... if you want lots of bass

below 50Hz in anything other than a small room with lots of bass gain, I'd go with a good sub.

Widget

[Duke Spinner]

at least the drivers are cheep ......[:|]

[Marvel]

Widget,

Nice of you to stop by here. I'm still wanting to build some Smith horns one of these days, even if they won't match the beauty of yours.

Bruce

[fini]

Shame on you! K-43 abuse is almost 5 times worse than kicking your dog!

[hwatkins]

Hello Widget -

Got any Lansing alternatives for our spinner friend that may get a bit closer to what he wants?

[Mr. Widget]

Widget,

Nice of you to stop by here. I'm still

wanting to build some Smith horns one of these days, even if they won't

match the beauty of yours.

Bruce

Thanks for the compliments... the Smith horns are quite nice

though they aren't the best choice if you need a crossover point below

1000Hz so they aren't really a good choice for most Klipsch based projects.

Hello Widget -

Got any Lansing alternatives for our spinner friend that may get a bit closer to what he wants?

I assume you mean a woofer substitution since we are talking about La

Scalas. Years ago I tried the JBL 2220 in a pair of Belle clones I had

made... they just didn't sound as good as the K33. I suppose the woofer

to try would be the K145 or the E145... they may offer an upgrade, but

as Duke pointed out at the top of this thread, he is fighting the laws

of physics with the small bass horn in the La Scala.

Widget