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Bottlehead Kits => Kaiju Stereo 300B amp => Topic started by: Jamus on November 26, 2017, 05:18:10 AM

Title: Value of a constant load for the Kaiju?
Post by: Jamus 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
Title: Re: Value of a constant load for the Kaiju?
Post by: Paul Birkeland 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.
Title: Re: Value of a constant load for the Kaiju?
Post by: Doc B. 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?
Title: Re: Value of a constant load for the Kaiju?
Post by: Jamus 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?
Title: Re: Value of a constant load for the Kaiju?
Post by: Paul Birkeland 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 (https://community.klipsch.com/uploads/monthly_02_2016/post-36163-0-65120000-1456026923.jpg)
Title: Re: Value of a constant load for the Kaiju?
Post by: denti alligator on November 27, 2017, 10:31:54 AM: I have Forte IIs and am using the Stereomour II at 4ohm. Sounds fantastic.
Title: Re: Value of a constant load for the Kaiju?
Post by: Jamus on November 27, 2017, 03:35:36 PM: Quote from: denti alligator on November 27, 2017, 10:31:54 AM
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.
Title: Re: Value of a constant load for the Kaiju?
Post by: denti alligator on November 28, 2017, 02:41:44 AM: I bought mine used with the Crites upgrade already installed.
Title: Re: Value of a constant load for the Kaiju?
Post by: Jamus 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