SEAS 5-INCH PROJECTS
Copyright 2008 © Troels Gravesen
Last updated 2016
Kit not supported by Jantzen Audio any more. Source components locally by dealers.
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The CA15RLY and W15LY001 versions from this project are finished and I'm left with the task of writing something about these drivers? Hmm...they're all good, but for various reasons. From the CA15RLY you get a dynamic little speaker that I'm sure will satisfy most if you know what you can expect from 75 cm^2 cone area. The W15LY001 costs more than twice the CA15RLY price and as always we apply to the law of diminishing return. The W15LY001 is a better driver. It provides a tad deeper bass and it can be driven a harder without noticeable distortion. But some may prefer the more vivid presentation from the cheaper brother.
I've used the 22TAF/G tweeter in other - not published - constructions, and once more I like what I hear from this small 3/4" dome with the wide surround. I haven't made the W15CY001 version yet and it's to be heard if this tiny fellow can match the HIQUPHON OWI tweeter used in the W15-OWI construction. They're both 3/4" domes but one is a classic, coated fabric dome and the other a hard dome made from aluminium. Due to the small diameter of the alu dome the inherent cone break-up seems to be as high as 30 kHz or more. And the wide surround makes us want to treat it as a 1" dome although we have to realise that the smaller voice coil won't take as much heat as a 1" voice coil, but from a 3rd order filter, this is not a problem as we won't play any of these three speakers excessively loud. Small minis are not for Saturday parties.
The CA15CY001 system is the "Joe-Cool" of the gang presented here. With 83 dB sensitivity it's slightly less dynamic compared to the other two, but the lack of colouration from the magnesium cone is hard to ignore. This speaker tells you very much what's on the recording, but in a non-aggressive way as can be the case from speakers with an elevated upper midrange or treble voicing.
Overall there's a steadily progression in clarity and naturalness going from the CA15RLY over the W15LY001 to the W15CY001 driver, with a wider gap between the CA15 and the W15LY compared to W15LY and W15CY. The latter two are close with the increased sensitivity of the W15LY being the key difference.
For TS data "added volume" method has been used. As always some discrepancy between claimed data and actual measurements. Dependent on actual signal applied to the units during measurements, we can have different results. No surprise.
For the W15LY001
(nextel coated driver) the correlation is good.
The magnesium driver is well used and still
maintain Fs = ~50 Hz. The CA15RLY is a lightly
coated paper cone and I wonder if this driver
really has higher Mms compared to W15LY001, as
claimed by SEAS.
The port: I've used Jantzen Audio #900023, 50 x 145 mm (Ø x L) for all drivers and cut it to 120 mm length.
front panel dimensions and driver placement. If
you make your own cabs, calculate cabinet depth
to make 11.5 litre internal volume, e.g. from 19
mm MDF approx. 200 x 350 x 270 mm outer
dimensions (W x H x D).
Left: SPL from
drivers at 2.8V, 1 metre distance. Blue
= W15CY001 (new), red = CA15RLY,
green = W15LY001.
Right: SPL from "new" and "old" W15CY001 magnesium driver. I had a mail from Finland suggesting differences between former and present 5" magnesium drivers and so it appears. I've got a pair of both. The newer drivers have a minor bend to the cone where it meets the voice coil, allowing a larger area for gluing - and this is pushing break-up nodes towards higher frequences - but also with higher amplitude. From initial modelling this doesn't make much difference to the crossover, but minor adjustments to the notch-filter have to be made. Actually the "old" driver appears easier on modelling due to lower impedance where we need correction to be done.
CA15RLY + 22TAF/G
Click image to view large.
built by Koen/Belgium
W15CY001 + 22TAF/G