FH3-inspired Foam Core Mini Build

Dayton in general don't tend to get much of a look in on DIYaudio relative to other units. Possibly down to them being in essence PE's house brand; they seem to get more air-time over on the PE forum &c. They can put out some decent - very good units; the RS28a for example is an excellent tweeter (Usher unit built for the brand). The PS220 also forms the basis of the Decware FRX2 which had some discussion here a couple of years back -as I recall (and I speak under correction since I haven't looked since then) it essentially takes said unit, and adds a steel-core tapped inductor before the motor, amongst other adaptations.
 
I took a filament transformer and made my guess of a Decware Gizmo (ignore the cap on the 1K pot - used that for testing effects) - lot of fun to get a solid state amp to sound kinda like a low damped tube amp on the fly and back by rotating the pot. The modified PS220 must have similar. I think Decware sells the Gizmo transformers.
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IIRC, one person (not me-lol) said PS220 was great in a Karlson 12 - could their test situation be making it look like there's built in BSC?? - for instance look at this 12" http://www.parts-express.com/pedocs/specs/295-032-dayton-audio-pa310-8-specifications-46883.pdf

I agree Dayton should change their vertical scale for the PS220 - how do they get it to bump up in the BSC area?
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I took a filament transformer and made my guess of a Decware Gizmo (ignore the cap on the 1K pot - used that for testing effects) - lot of fun to get a solid state amp to sound kinda like a low damped tube amp on the fly and back by rotating the pot.

This looks interesting, which driver did you try it in and what amp were you using? So it is a "dial a tube" sound effect? Meaning extra 2nd harmonic distortion? Will it work with a class D amp or only class A or A/B?
 
it just varies the output Z (not in an entirely linear fashion) - would work with any amp/speaker for playing around. I took posted Z measurements some years back - if you've got a filament transformer, etc with a low dcr winding on the low voltage winding then give it a whirl. It would be interesting to know what xformer spec Decware used. I don't even know if Decware runs their Gizmo this way. I ran some caps in parallel with the R on the primary to see the reflected results.

http://www.decware.com/paper30.htm

a 1K pot seemed about right for adjusting the 120V side of the 6.3vct transformer

Output Z

508 ohm on 120 volt winding
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1005 ohm on 120 volt winding
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508 ohms paralleled with 0.1uF on 120 volt winding
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508 ohms paralleled with 3.3uF on 120 volt winding
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1005 ohms paralleled with 3.3uF on 120 volt winding
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1005 ohms paralleled with 15uF on 120 volt winding
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1005 ohms on 120 volt winding. 3.3uF across low voltage winding
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PS220 in a Karlsonator

Kind of OT but here it is in a 1x scale in height and depth x 0.8x width. Needs a BSC to tame rising response though (6 ohms + 1 mH).
 

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A simulation can't predict if the 220 is better than the 1772 - there is stuff in the freq response that is so dependent on driver design like cone breakup and dips and peaks - but in terms of efficiency and bass extension they look about the same. With the 220 coating less - it may be more attractive. The problem has been that there are so few builds with the ps220 that the word of mouth endorsement required to overcome any reluctance hasn't really happened yet. There is the one thread going on now with the 220 in a MLTL so that may help get things going.