Interesting. How did he do that?
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I donāt know, you can get in touch with mr. Sandro Lotti at LASA Piacenza
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Does he still walk around in that white lab coat?
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He does usually 
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Thatās actually quite common. Although of course thatās never the intent of the design, merely a result of it. In my speakers the mid unit has reversed polarity.
As @Mike-B says, there can be a difference in electrical and acoustic phase.
Try searching for Custom Analogue Audio article Renegade Tweeter Theory
I donāt have my allaes to hand but if the wires going into the plug for the tweeter donāt have the web between them near the plug you can remove the plug body, the pins should push out with a bit of effort, and swap which holes the pins go in, just turn off the amp or pull the speaker cable from the cross over while thereās a chance of a short, though you might get away with it, thereās usually an inline CAP on a tweeter feed but best not to rely on that.
Iām going to run a phase alignment test on the tweeters this weekend. Weāll see if that improves things. But honestly, Iām not too optimisticā¦ And even if it were better, it still wouldnāt be optimal. During the design of the Allae and PXO, the latter was specifically adapted to the physical, electrical, and acoustic characteristics of the Scanspeak, just like the woofer.
Therefore, any replacement component wonāt be compatible (unless itās identical to the original) and will create an imbalance in the crossover, unless everything is readjustedā¦ I suspect Iām not the only one whoās changed tweeters, and feedback from SBL, Allae, or SL2 owners would be interesting: replacement with an original model or not? What are your impressions?
Why then did you opt for the Hiquphon?
Still struggling with one of the concepts arising in this thread: I am willing to bet that musical instruments do not have frequency related phase reversal built into them.
Neither do the drivers have it ābuilt into themā.
Troels Gravesen has a nice, relatively simple, explanation on his site. Unfortunately I canāt link to it, but if you search for āTroels inverted polarityā it should come up.
On paper, and after asking Oskar Wroending (Hiquphon) if the OW2 was a good replacement for the Scanspeak D2008, upon further investigation, I realize it doesnāt work and the made of an filter is no tolĆ©rant with approximative values. In any case, I should have stuck with the original replacement, which would have saved me from this mess. New problem: finding D2008sā¦
This must be frustrating, yes the solder is not really going to make much difference at all. Loudspeakers are carefully constructed and balanced in terms of performance and drivers are not usually plug and play.. the speaker cab, crossover, baffle etc are carefully optimised to the very specific characteristics of the drivers.
As said above try let it run it for a bit ā¦ back to back out of phase on mono helps, but I suspect that wonāt make a significant difference.
You could contact Naim if not already and see what they suggest.
Simon
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Iām not sure that the manufacturer was ripping you off any more than any manufacturer extolling the virtues of their products, as long as what they claimed about their tweeter was factually correct. It might be a better tweeter than the Scanspeak technicaly, but not necessarily better to any individualās ears: e.g. a tweeter could have a perfectly flat response throughout its range, but the speaker designer, aware of variations in response might design the crossover to level it out, that then not being level if a level response tweeter is fitted. Also of course any given person may prefer the sound of one that is far from flat!
Re sourcing a replacement, In his post earlier in this thread @Richard.Dane referred to new Scanspeak tweeters, though he didnāt give a model number.
IIRC itās the Scanspeak D2008/852100 (no ferrofluid), the replacement for the original D2008/851100.
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ā¦..I meant, more precisely, that the speaker as a whole, rather than the individual drivers, have a phase anomaly: that the drivers are out of phase with each other. If I listen to someone isinging, their vocal cords do not conspire to somehow have different parts of their frequency range our of phase with each other.
I have a matched pair set of Scanspeak D2010/851100 that I purchased as a backup should I have issues with the ones in my NBLs (hopefully never need, but ā¦.). They were available new from a UK distributor (Falcon Acoustics) but that was apparently a limited production run by Scanspeak for them. May be worth contacting them if they still have a set hidden in the back somewhere.
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And these drivers, part of the Scanspeak Classic Range, are available from Falcon Acousticsā¦ and are quite reasonably priced so shouldnāt be an issue obtaining and swapping out
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I think those are the newer version that are not exactly the same and have four screw holes instead of three.
I replaced the tweeters on my SL2s with original models. It was a clear improvement.
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