Value of a constant load for the Kaiju?

Jamus · 3015

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Offline Jamus

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on: November 26, 2017, 05:18:10 AM
Having recently purchased some vintage Klipsch Forte speakers I've been doing some reading about crossover upgrades. It has been mentioned that the original crossover design of the Klipsch can produce a widely variable load (up to 70 Ohm, apparently) which can be problematic for low powered SET amps. There is an aftermarket crossover design by ALK which produces a stable 8 Ohm load. Does this seem like a valuable upgrade or is this a solution looking for a problem?
Thanks!
Jamus

Rega Planar3/Elys2 - Eros - BeePre - Kaiju - Klipsch Forte I's
Marantz CD5005
Crack w/Speedball - Senn HD650


Offline Paul Birkeland

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Reply #1 on: November 26, 2017, 06:23:50 AM
The bigger issue with SET amplifiers are speakers with an 8 Ohm rating that have low portions of the impedance curve.  Flattening out the high spots may or may not be helpful.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Doc B.

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Reply #2 on: November 26, 2017, 06:28:31 AM
What PB says, and also a different crossover can sound different for other reasons besides impedance compensation, like changes in crossover frequencies or order, materials used, insertion losses, etc. So the more important question might be which crossover sounds better?

Dan "Doc B." Schmalle
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Bottlehead Corp.


Offline Jamus

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Reply #3 on: November 27, 2017, 02:04:40 AM
I read they can draw as low as 3.7 ohms. Would this warrant switching the Kaiju over to the 4ohm taps?

Rega Planar3/Elys2 - Eros - BeePre - Kaiju - Klipsch Forte I's
Marantz CD5005
Crack w/Speedball - Senn HD650


Offline Paul Birkeland

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Reply #4 on: November 27, 2017, 03:47:50 AM
I'd certainly recommend trying both.  Using the 4 Ohm tap will give you better damping (bass control), lower distortion, lower noise, but also lower power. 

The Forte looks to have one dip in the lower mid-range, but is otherwise not too unfriendly.
 Forte Impedance Curve

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline denti alligator

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Reply #5 on: November 27, 2017, 10:31:54 AM
I have Forte IIs and am using the Stereomour II at 4ohm. Sounds fantastic.

- Sam

Rega P3-24 (w/AT 150MLX) w/Groovetracer upgrades / Eros II / FLAC >J.River >DSD256 >Gustard X20 / Moreplay > Stereomour II / Klipsch Forte II w/Crites upgrades / C4S S.E.X. 2.0 +Nickel MQ Iron / Speedball Crack / Sennheiser HD600 w/Cardas cable


Offline Jamus

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Reply #6 on: November 27, 2017, 03:35:36 PM
I have Forte IIs and am using the Stereomour II at 4ohm. Sounds fantastic.

Thanks Sam!
Did you do the Crites upgrade yourself or buy them already upgraded? I'm considering Crites vs ALK crossovers.

Rega Planar3/Elys2 - Eros - BeePre - Kaiju - Klipsch Forte I's
Marantz CD5005
Crack w/Speedball - Senn HD650


Offline denti alligator

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Reply #7 on: November 28, 2017, 02:41:44 AM
I bought mine used with the Crites upgrade already installed.

- Sam

Rega P3-24 (w/AT 150MLX) w/Groovetracer upgrades / Eros II / FLAC >J.River >DSD256 >Gustard X20 / Moreplay > Stereomour II / Klipsch Forte II w/Crites upgrades / C4S S.E.X. 2.0 +Nickel MQ Iron / Speedball Crack / Sennheiser HD600 w/Cardas cable


Offline Jamus

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Reply #8 on: December 04, 2017, 12:11:22 PM
Just thought I'd circle back to say I switched over to the 4 ohm taps and it is just as advertised (though still plenty of power). Really glad I did and thanks all for the advice.
Jamus

Rega Planar3/Elys2 - Eros - BeePre - Kaiju - Klipsch Forte I's
Marantz CD5005
Crack w/Speedball - Senn HD650