Freighter Posted July 4, 2021 Share Posted July 4, 2021 (edited) So I've had my Cornwall IV's bi-amped for a while, but I was just going through the manual for something unrelated when I noticed the bi-amping diagram. The diagram seems to suggest that the H (high) wires need to be reversed. The diagram shows the high '-' on the speaker being connected to the '+' on the amplifier. This would put the highs out of phase with the lows. I was just wondering if this is a printing error or if this is actually intended/necessary? Edited July 5, 2021 by Freighter Changed Cornwall V to Cornwall IV, oops Quote Link to comment Share on other sites More sharing options...
dtr20 Posted July 4, 2021 Share Posted July 4, 2021 Pretty sure this is a printing error Quote Link to comment Share on other sites More sharing options...
Edgar Posted July 4, 2021 Share Posted July 4, 2021 "A second order crossover will shift the phase of each speaker 90 degrees, so that both speakers are 180 degrees out of phase. This means that at the crossover frequency, the two drivers will be moving in opposite directions at the same time. They will cancel each other out and produce a 30db dip in the frequency response at the crossover point. Reversing polarity of one (but not both) of the speakers will limit this dip to +- 3db." https://www.diyaudioandvideo.com/Calculator/SpeakerCrossover/Help/ Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted July 4, 2021 Share Posted July 4, 2021 I say it is a mistake in the owners manual. I would assume any needed polarity changes as it relates to the passive crossover function would be done internally and not at the external input connections. As can be seen in the bi-wire example there is no polarity reversal at the amplifier connections or input terminal connections. Also if just using the standard jumpers there are no external polarity reversal. All this adds up to a manual misprint/mistake. This is also assuming you are using identical amplifiers for HF and LF. miketn Quote Link to comment Share on other sites More sharing options...
Edgar Posted July 4, 2021 Share Posted July 4, 2021 2 minutes ago, mikebse2a3 said: I would assume any needed polarity changes as it relates to the passive crossover function would be done internally and not at the external input connections. As can be seen in the bi-wire example there is no polarity reversal at the amplifier connections or input terminal connections. Also if just using the standard jumpers there are no external polarity reversal. That's a good point that I completely missed. I agree with your conclusion. Quote Link to comment Share on other sites More sharing options...
wuzzzer Posted July 4, 2021 Share Posted July 4, 2021 Cornwall V?? 🤷♂️ 1 Quote Link to comment Share on other sites More sharing options...
Moderators Travis In Austin Posted July 4, 2021 Moderators Share Posted July 4, 2021 @Chief bonehead @Trey Cannon are you aware of this? Can you confirm this is an error. @Paducah Home Theater do you have any experience with this? @Edgar @mikebse2a3 if the OP tried it both ways, it wouldn't hurt anything I'm assuming? (Amp or speaker) I thought there was at least one Heritage balancing network in the bast that reversed the phase on one of the drivers? EDIT: As Mike and Edgar covered, the jumpers would make the phase change by network moot, that would be handled internally. 2 Quote Link to comment Share on other sites More sharing options...
OO1 Posted July 4, 2021 Share Posted July 4, 2021 6 hours ago, Freighter said: I was just wondering if this is a printing error or if this is actually intended/necessary? I checked all the Heresy IV -Forte IV and Cornwall IV -Lascala AL-5 , user manuals ----same thing , so it is intended Quote Link to comment Share on other sites More sharing options...
Edgar Posted July 4, 2021 Share Posted July 4, 2021 56 minutes ago, dwilawyer said: @Edgar @mikebse2a3 if the OP tried it both ways, it wouldn't hurt anything I'm assuming? (Amp or speaker) Unless there's something really weird going on inside, it shouldn't damage anything but the sound quality. @Chief bonehead should have the definitive answer. 1 Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted July 4, 2021 Share Posted July 4, 2021 28 minutes ago, 001 said: I checked all the Heresy IV -Forte IV and Cornwall IV -Lascala AL-5 , user manuals ----same thing , so it is intended Heresy lV is correct Forte lV is incorrect Cornwall lV is incorrect La Scala AL5 is incorrect Again Look at the bi-wire hookup which shows same polarity for LF and HF with again no polarity reversal. Also realize that if using a single amplifier with jumpers installed the HF and LF have the same polarity in effect and the same thing applies in the bi-wire hookup so it would make no logical sense to reverse polarity when bi-amping if using identical amplifiers for LF and HF. Only in the special case of using unlike amplifiers for HF versus LF and one of the amplifiers itself inverts polarity at its output would a polarity reversal be necessary. miketn 3 Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted July 4, 2021 Share Posted July 4, 2021 32 minutes ago, Edgar said: Unless there's something really weird going on inside, it shouldn't damage anything but the sound quality. @Chief bonehead should have the definitive answer. Agree only sound quality would be less than optimum. miketn 1 Quote Link to comment Share on other sites More sharing options...
Klipsch Employees Chief bonehead Posted July 5, 2021 Klipsch Employees Share Posted July 5, 2021 The forte, Cornwall and la scala are incorrect. The heresy is correct. I have alerted the marketing guys. Thanks. 5 2 Quote Link to comment Share on other sites More sharing options...
Freighter Posted July 5, 2021 Author Share Posted July 5, 2021 Thanks guys! I thought it must be a misprint, because it made no sense, and also they sound fantastic - I imagine I would've noticed if it wasn't intended. However, it's good to know that it's a misprint. 2 Quote Link to comment Share on other sites More sharing options...
salbake Posted July 6, 2021 Share Posted July 6, 2021 A. This thread is way over my head, but I really enjoyed reading it. B. Are my Cornwall IVs more valuable now as long as I hang onto the manual? “Rare misprint, limited run edition,”…..?? 🧐😜 1 Quote Link to comment Share on other sites More sharing options...
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