2007 TLs

[planet10]

Originally Posted by Scottmoose

I'm not really much of a fan of metal cones

If you look at the FR of the woofer in the Thor you can see a nearly 10 dB resonant peak in the FR. People who design in the frequency domain would say notch filter + XO no problem, but there is no way to get rid of the subtler IM effects of that honking big bell.

The other design features i have with the Thor is that it is an MTM, uses a dome tweeter, and has a crossover right in critical telephone range (the WD25 also suffers from a dome, but has a much simplier crossover).

My take on a modern TL would be something like the SEAS driver in the WD25 actively driven + a miniMonitor of your choice built in -- i would consider a Fostex FE 108eZ in a tube aperiodic transmission line opening on the back of the box, plus either a ribbon (like AC 2sii) or horn FT17 crossing in at 7-10k.

dave

[Scottmoose]

I reckon we better design one Dave...

That would be pretty much my top choice too. I don't mind XOs per se, but I prefer them pushed out of the critical regions, & using a whizzerless FR unit WR to cover that is about ideal.

[planet10]

Actually we already have one in the queue... althou with my development of a triangulated line (i've yet to see a similar one published -- doesn't mean it doesn't exist) that you modeled for the Jordan JX150 -- but we better find some 8 & 10" woofers that are more available. Once the line is developed for the woofer, people can add their own mid-top -- prefereably active on the bottom.

dave

[Scottmoose]

Sounds a plan to me.

[planet10]

Any suggestions for woofers?

8 & 10"
natural cone material
FR up to at least 1k (target XO 200-250 Hz -- tied in with baffle width)
90+ dB efficient would be nice
either an effective dustcap or an easily removable one
doesn't break the bank (nothing stopping us from having 4 basic boxes for budget drivers and more than buget driver)

Qt 0.3-0.4
Fs 25-30 Hz
Vas not too small, but the smaller it is above that, the smaller the box (usually at the expense of efficiency)

Scott can fine tune those numbers. To be a classic drivers need to work in a daline/tapered ipe TL. Tuning can be adjusted for anywhere between Radford/Bailey bass or IMF/TDL/PMC bass (ie dependent on room)

dave

[Scottmoose]

Just so long as nobody suggests Volt drivers, they're a pain in the backside to get loaded right...

The Dayton ST255-8 looks an excellent candidate. Parameters are pretty-much spot on, and it's not too expensive. Same goes for the Monacor SPH-255.

The Seas A26RE4 that's used in the WD kits and our new TL version has almost all these attributes, missing out only on sensitivity: 89db 1w rather than 90db. Bit pricier though.

[planet10]

Originally Posted by Scottmoose

The Dayton ST255-8 looks an excellent candidate.

i don't know... Fs a bit high and the FR gets awfully ugly up high. Also has a vented pole piece.

Monacor SPH-255.

Don't know that one.

The Seas A26RE4 that's used in the WD kits and our new TL version has almost all these attributes, missing out only on sensitivity: 89db 1w rather than 90db. Bit pricier though.

That one we know... same as this?

http://www.madisound.com/cgi-bin/ind...13118&pid=2017

There is also an 8"

[planet10]

Originally Posted by Scottmoose

The Dayton ST255-8 looks an excellent candidate.

i don't know... Fs a bit high and the FR gets awfully ugly up high. Also has a vented pole piece.

Monacor SPH-255.

Don't know that one.

The Seas A26RE4 that's used in the WD kits and our new TL version has almost all these attributes, missing out only on sensitivity: 89db 1w rather than 90db. Bit pricier though.

That one we know... same as this?

http://www.madisound.com/cgi-bin/ind...13118&pid=2017

There is also an 8"

dave

[andrew ivimey]

and when you two boys have stopped playing with yourselves!

[richardcooper2k]

i do like reading the sound of brains rubbing creatively together !