I would hate to go with 5" drivers then wished I had bought the 7". Scanspeak 7" drivers and actually 6.5" drivers.
On a second thought what if I went with 7" and a 5", would it split the difference?
On a second thought what if I went with 7" and a 5", would it split the difference?
I think you will be OK with the 18WU/8741T as long as you cross it to the 2904 in the 1.6 k to 1.8 k region.
Others may chime in to warn you about vertical dispersion or directivity issues, but since you are going with an MTM or WMTMW design anyway, you have already made the choice to have a narrowed vertical polar response.
This is an exciting project. What hardware are you planning to use for amps and crossover filters?
Others may chime in to warn you about vertical dispersion or directivity issues, but since you are going with an MTM or WMTMW design anyway, you have already made the choice to have a narrowed vertical polar response.
This is an exciting project. What hardware are you planning to use for amps and crossover filters?
yelp, i figured my first choice is the one I could live with..
equipment:
Jriver with Acourate-SW
MOTU interface to get it off the ground
Parasound 2205 and looking at a HCA-3500 or A21 for bass..
On a quiet tip... Ive got a really evil notion to buy a Pass X350 for my birthday...
equipment:
Jriver with Acourate-SW
MOTU interface to get it off the ground
Parasound 2205 and looking at a HCA-3500 or A21 for bass..
On a quiet tip... Ive got a really evil notion to buy a Pass X350 for my birthday...
Will be linearizing all drivers with software but I was wondering if parallel wiring the 7" mids has drawbacks. Im considering buying another 2205 for the ability to wire and linearize each driver independently. Would there be creditable gains?
As far as I can see, in an active home system, there is one main reason to go for bigger mids:
--> to get slightly more LF capability (lower crossover)
...and one niche reason:
--> where narrowing HF dispersion is a desired trait (e.g. the Geddes speakers, and most "econowave" type builds use a single big midwoofer for this reason)
To examine the main reason, punch some numbers into an excursion calculator:
Piston Excursion calculator
--> 5" crossed at 200Hz is good for 100dB with 1mm excursion.
--> 7" crossed at 150Hz is good for 100dB with 1mm excursion.
That's your trade off.
If you want to cross lower, bigger drivers make sense.
You could do it, if you have enough amp channels.
However, is it worth it?
Which driver will be the weaker link, for the crossover points you intend to use?
2*5" mids playing to 150Hz: 100 dB from 1mm excursion
2*11" woofers playing to 30Hz: 100 dB requires 5mm
This is an over simplification, but I think it illustrates that a pair of 5" midwoofers (or a single 7") will be sufficient (not the weak link) unless your crossover is quite low.
--> 5" crossed at 200Hz is good for 100dB with 1mm excursion.
--> 7" crossed at 150Hz is good for 100dB with 1mm excursion.
In a way, this justifies 7"s for further substance in the upper bass regions above the 11"s. Ofcourse the 7"s will handle most of the work load in the freq range, the only drawback is quickness.... Full disclosure, Ive never been a fan of 5' drivers, my very first system was a MTM wt 7". But I can always add a single 5" in the future.
--> 7" crossed at 150Hz is good for 100dB with 1mm excursion.
In a way, this justifies 7"s for further substance in the upper bass regions above the 11"s. Ofcourse the 7"s will handle most of the work load in the freq range, the only drawback is quickness.... Full disclosure, Ive never been a fan of 5' drivers, my very first system was a MTM wt 7". But I can always add a single 5" in the future.
R2904 is ringradiator, generally ringradiators do not like low crossover points. Did you consider 7100?
I would suggest to add waveguide like wg148 or one of Augerpro waveguides, use 7100 and try crossover below 2k. Also cut both mids into waveguide to minimize CtC.
Bliesma t34b would be also step in the right direction.
I would suggest to add waveguide like wg148 or one of Augerpro waveguides, use 7100 and try crossover below 2k. Also cut both mids into waveguide to minimize CtC.
Bliesma t34b would be also step in the right direction.
Last edited:
+1
The Bliesma T34B would be an excellent tweeter for your project. It has very high output, very high sensitivity, flat response, and the distortion is low even down at 1 kHz (very hard to achieve in tweeters). I would be comfortable crossing this tweeter at 1.5k with 24dB/octave slope in a high SPL application.
The Bliesma T34B would be an excellent tweeter for your project. It has very high output, very high sensitivity, flat response, and the distortion is low even down at 1 kHz (very hard to achieve in tweeters). I would be comfortable crossing this tweeter at 1.5k with 24dB/octave slope in a high SPL application.
i really like Beryllium drivers and I intend to maybe upgrade this build in the future. For now Im comfortable with traditional tweeters and the choice ive made.
Still not really sure about going with 6.5 inch woofers, 5.5 inch woofers could be better synergy and mids.
