Looking for tweeter for my MTMs...suggestions?

[roundel325]

I'm looking for a nice tweeter to go into my MTM project. I'm striving for good efficiency with a modest (to some people I guess) budget. <$450 would be nice... Anyway, I think I'm gonna use Hi-Vi's M6N wired in parallel for midbass. So I need something like a 95 or 96 db/watt/meter 4 ohm tweeter. I've searched around a bit, and nothing really jumps out as a good match. I don't exactly know what type of tweeter is my favorite. I have heard metal and silk domes and find them both acceptable. Ribbons and planars are neat, and I like their quick sound, but I don't want something with horrible off-axis responce. Will be listening to classic rock, blues, jazz... I'd appreciate any suggestions. Thanks.

-Jared

[coolkhoa]

The Hi-Vi planars have good efficiency, but I don't know how they sound. As a plus, they have yellow membranes, which sorta matches your woofer.

Alternatively, you may want to consider horn-loaded tweeters from Morel, Vifa, etc.

[sreten]

Unless you are using line level baffle step compensation
you will find most tweeters above 89dB/W will be suitable.

After BSC the mid band sensisitivity of your 2 units is 88dB/W.

sreten.

[roundel325]

A few more questions... What is baffel step correction? Why do I need it? How is it implimented? I have only heard the term in reference to single full range drivers. Thanks.

-Jared

[roundel325]

Alright, sorry for the premature post. I googled baffle step compensation and I see what you are talking about. Here is my situation... I have a 4 watt single ended tube amp that I will be driving these speakers with. My listening room is small (12x12), so I will probably never be more than a few meters from the speakers. Also, since the room is small, big enclosures are not a possibility. So I'm hoping for a sensitivity in the low 90's. I chose the M6n because it has above average sensitivity for a 6.5" and also good low end extension. I chose MTM only to get annother 3db. Would it be better for me to go 2.5 or something? I don't think bipole is an option because the speakers will be too close to the wall.
Ultimately I am looking for a small speaker with decent efficiency. I'm open to any suggestions, although I don't think full range drivers are for me.... Thanks again.

-Jared

[sreten]

4 watts single ended ? Hmm.........

MTM 2 way or TMM 2.5 way will be needed.

A TMM is less tall but good designs are hard to find.

So probably an MTM with BSC in the crossover.

If 4 ohms loading is OK with the amplifier you have a lot of choice.

If 4 ohm loading is not ok you'll need to use 16ohm (12R) units
e.g. as found here :

http://www.gr-research.com/drivers.htm

Basically the sensitivity of the driver you choose
will be the midband sensitivity of the speaker.

Simply put once you've decided your enclosure size you are
trading off bass extension for mid band sensitivity, with 4
watts on tap worrying about bass too much is not a good
idea.

Personally I'd use stereo powered subwoofers as stands
for a high efficiency 8 ohm sealed 2-way with line level BSC.
Box Q 0.6 to form half of a 2nd order L/R crossover

The subs would be driven from the loudspeaker output
of the amplifier and TBH wouldn't need much power.

Or a miniature version of this :

http://www.deadwaxcafe.com/vzone/david/david.htm

Note the baffle step compensation arrangements.

But with the bass modules actively driven, again
from the loudspeaker output of the amplifier.

sreten.