best 4.5" midrange drivers under $1K

Hi folks,

was wondering if any could give suggestion for best midrange. prefer it can make clean audible output down to 100-150Hz, flat up to 5KHz, and has non-paper cone. currently using seas excel wcyex001 in a 3-way setup (alumunium ribbon en fiberglass midbass).

@cdc: thanks for the zaph's website, its very useful indeed, wonder if he can test Flex 4" and Accutons
@shadorne: Im trying to find to best my excel midrange, i know theyr colder than paper but to me they deliver clear and as-is presentation
@shadorne: Im trying to find to best my excel midrange, i know theyr colder than paper but to me they deliver clear and as-is presentation

Shadorne, I would guess you are a fan of the dome midrange? What material?

If Audioism is looking for highly regarded midrange drivers then the ATC SM75-150S should be on his list.

There is a guy called SHINOBIWAN who has done extensive DIY using the driver - I'd google/contact him for help if you are intrigued. Some people really like to criticize it - but it has been around for more than two decades - so it is pretty popular despite being expensive.

The problem is that this driver is so powerful that I am not sure if any ribbon could keep up. It also needs sharp crossover filtering and distortion rises rapidly at low levels. Basically Audioism would need to start a design from scratch - so I did not suggest it.

It is apparently the only dual spider midrange dome in existance apart from a version by PMC which is apparently similar to its junior brother the SM75-150 - non "s" verison. The engineering/tolerances are painful and most other midrange domes (like the Vifa) will distort all too quickly at even modest volume levels - so midrange domes are not such a good choice in general especially cheap ones. This picture shows the "S" on the left and its junior brother on the right. Needless to say this is an absolutely massive drive motor for a 3" doped fabric dome (3" Voice coil) - in fact it far bigger than the vast majority of woofers. It is generally regarded as sounding faster than anything else except perhaps electrostatics (but will naturally go way louder than panels). It is also regarded as an expensive and difficult driver to match and best executed in an active design. Not something to start a DIY with, IMHO.
Well I always believed that paper was a good material for cones insofar as the weight of the material itself is concerned, but that it was more subject to temperature changes and would distort more than metal or plastics. In my second system I have a pair of Rega NAOS speakers that have paper drivers and these speaker,at least to my ears, have excellent transient response.

I do agree that getting good integration between ribbon tweeters and cone drivers is a daunting task.

What did Proac use as a midrange driver in its models with a ribbon tweeter? In the same manner, what is used by Piega? This could give you some insight.
Try 6,5" Lowthers and reconsider paper. It's very fast, hopefully not much faster than yr tweet. The drivers mentioned above, excellent though they are, are very difficult to work with and, I speculate, mismatched sonically with yr alu & fiberglass.
I would further recommend you reconsider the request for a 4,5" to play 150Hz and look for a bigger boy: say, 8".
I totally agree with Gregm. I would be tempted to double up on most 4.5" midranges when working to 150 Hz. I am skeptical that even the accutons could work well that low even if doubled up at all but the most modest of volumes.

Pulp Paper is underated. It is very fast. It is also resonably damped inmternally (the big issue you get when you go metal/ceramic is "ringing" and the need to consider notch filtering to reduce its audibility).