kb2 50 watt or kb3 60 watt

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tcr1030
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kb2 50 watt or kb3 60 watt

Post by tcr1030 » Mon Oct 04, 2021 4:10 pm

I am having trouble deciding on which Peavey amp to purchase - the KB2 50 watt or the kb3 60 watt. This is for home use only at this point. I will be connecting a Hammond b3 clone to the amp and also be playing along with mp3's. My living room is approx 350 sq feet with 8 foot ceilings. I want some volume but it doesn't need to be ear piercing by any means. I also have an electric piano but the majority of the louder volumes would be coming from the Hammond and mp3 playing. Any suggestions would be welcome. This would be my first amp purchase and would be replacing some worn out/blown Roland MA 12-C 16 watt powered speakers. Thanks

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Enzo
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Re: kb2 50 watt or kb3 60 watt

Post by Enzo » Tue Oct 05, 2021 10:55 am

Imagine looking at a new car choice. One has a 110 horsepower engine and the other a 120 horsepower engine. Would you expect a real difference in performance? The 50 versus 60 watt difference would not be audible.

I assume these are used amps. SO look at them in terms of condition. In my mind, a older amp in great shape is better than a newer amp that is beat up. DO all the controls work? Or are they noisy/scratchy when turned? DO all features work? I don't recall these models specifically, so if there is a difference in speakers, consider that. If one has a large speaker, it may have a better bottom end for the organ sounds.

Breakinger
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Re: kb2 50 watt or kb3 60 watt

Post by Breakinger » Sun Nov 21, 2021 5:52 am

KB2 50 is a great amp. I have it and I am satisfied

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dak
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Re: kb2 50 watt or kb3 60 watt

Post by dak » Fri Dec 24, 2021 5:48 pm

"Hammond B3 clone" seems to me the main factor. The pedal starts with a C1 at about 32Hz. The KB2 has a 10" speaker and no external speaker connection. The KB3 has a 12" speaker (which means almost 50% more area for moving air on the low notes) and an external speaker connection. I cannot find a frequency range in the respective specs but as a reference, the KB300 has a 15" speaker and uses a lo-cut at about 35Hz or so in the preamp and probably knows why. Neither of the speakers you look at will likely support the low range of the B3 at the fundamental frequency: the kind of high-efficiency speakers used in instrument amps have big magnets and comparatively stiff suspension and as a consequence usually a resonance frequency a bit on the high side, with frequency response falling off below. So you likely want to pick the larger speaker here, and you want to pick the amp with an external speaker connector in case you come across some cheap old oversized passive box for keyboard or maybe even bass.

Though of course it depends on the kind of music you intend on playing. For rock, you likely don't need to cover the whole bass frequency range. A bass guitar starts at E1 (43Hz) and unless you care for the substance of the fundamental frequencies, the actual sound with musical relevance starts mostly with the overtones at double and beyond. So if you tend to register your pedals with quite more than the fundamental, you can skimp a bit on the low frequencies. The downside being that then the higher frequencies become more crowded, and to cover them reasonably transparently, you don't want too low power either.

Long rant short: personally I'd rather lean towards the KB3 and wouldn't bank on this being the last speaker you buy before you consider yourself settled for good. And if you intend to fill the room with low flute-like tones deep in the pedal, you'll have to rethink your approach since that just requires moving a lot of air. Which has a second corollary: if you have neighbors in the same building, veracity in the low frequencies is likely not a sustainable objective for home practice anyway, so the smaller amp may already give you everything you can actually make use of at home. Because while the low frequencies require considerable effort to produce, they also require considerable effort to contain.

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dak
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Re: kb2 50 watt or kb3 60 watt

Post by dak » Tue Jul 19, 2022 9:14 am

An afterthought to 45W+12W vs 60W (the rated RMS specs): the tweeters in both KB2 and KB3 appear to be the same, but biamping instead of a passive crossover makes most sense when the efficiencies of woofer and tweeter differ significantly. So it is quite likely that the efficiencies of the KB2 and KB3 bass speakers (10" vs 12" I think) differ enough to warrant biamping for the former, with (for example) -3dB corresponding to a halving of the sound energy.

The difference in loudness might be quite more than what would be attributable to the difference in electric power consumption.

In essence, one should not assign too much relevance to the electric power rating. Though I have to admit that it really annoys me when a Japanese competitor starting with R offers amps specified to deliver 300W of power while drawing 94W from the mains. While electric power output does not tell the whole story, it's at least relevant. And I read enough reviews of the kind "this Peavey has just $x watts but blows away the amp from $y that has all of $z watts".

Certainly hope that Peavey never succumbs to offering "better comparable" numbers that are similarly meaningless.

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