Fast, fun, Inexpensive OB project

It was suggested that two tweeters, close mounted be used, but that was rejected due to interference issues between the two tweeters. This may be too simple but why no use tweeters and roll one off where, or just before the
interference becomes an issue. Like the .5 setup that is often used at the bass
end. Any interference may still be there be there but reduced and reduced still more as frequency and roll of increases. I was looking into this idea using two to four of some of the recently released very small cone speakers.
jamikl
 
The Foutain-tech is very typical, in that it is very low efficiency, and with it's rising response, requires a LOT of work to flaten out. And most of the 3" class full range units I have tested just do not have any air to them.

Another issue is the Peerless is so clean in the lower midrange, what ever you mate with it better be good. The Peerless will show it up.
 
3 way Manzanita

A three way is do-able. And can be a "next level" performer. As usual, just comes down to doing the work. As I previously posted, I have put together a few three way configurations. The crossover is where you will spend a lot of time. It will be interesting to see what evolves in this area.
 
I've done a 3 ways but a floorstander. It is an other loudspeaker, a "next level" performer ;). It could be the classical comparison between a three ways and a two ways : better extension, better dispersion, lower intermodulation distortion etc. The drivers works in more linear area than the two ways. The crossover is much harder to tune. It took me two years to find an acceptable configuration to my ears.

But I still think a two ways is very useful, as a monitor for example. The enclosure is more compact.
 
OK, the current Manzanita uses the following components & layout. I can’t seem to get my scanner up and running, computer challenged lately. Panomaniac will verify that!! So I will describe the set up as best I can.

The Peerless woofer is a simple 1st order electrical low-pass using a 22 MH 16 ga. Erse Super Q iron core inductor wired in series to woofer positive. Anything from 18 – 22 MH iron core of 15-18 Ga. will work well. Woofer negative to ground. Larger Ga is better and keeps insertion loses to a minimum.

BTW, both drivers are wired in positive polarity.

The Scan Speak D3800 HF is way more complicated. It is a staggered 2nd order electrical high pass with pad and series resonance damping trap. The trap consists of 10 ohm mils resistor, 50 MFD metalized Polypro & 2.75 MH 15 ga iron core. This goes directly across the tweeter. It may have to be adjusted based on the actual resonance your tweeter(s) happens to have. IIRC, the above trap is correct for about 360 Hz. If the trap is not just right, the D3800 will have some edge to it and become congested at higher volume levels.

The HF pad is a 13 ohm resistor in series with the tweeter positive without a shunt. 20 watt minimum rating is recommended. You will lose some definition if you use cheap sand cast resistors. 6 & 7 ohm mils 10 watt in series is a good way to go. More on the pad later.

The 2nd order electrical includes 5.93 MFD cap (I happen to use a Solen 5.6 MFD with a parallel Dayton 0.33) in series with the tweeter positive prior to the series pad.

The last piece is an 8 MH 15 ga. Iron core shunt inductor with one end on the tweeter positive leg AFTER the pad resistor and the other leg to ground. The final connection is tweeter negative to ground. You can play with the shunt and connect one end after the cap and prior to the pad and see if that works better for you.

I have found that in small rooms and or near field listening situations, the Pad may need to be reduced by 0.5 to 1.0 ohm to maintain tonal balance and near field power response. You may want to add a small cap across the pad to provide some increased HF output above 13K. Suggest 0.33 to 0.75 MFD. Optional and YMMV.

The system can handle about 100 watts of program material before you run out of woofer or tweeter. This can deliver about 100 db or so of output (brief peaks). The system L.F. cut off is about 40 HZ and is dependent on the distance from the rear wall and or side boundaries. Baffle face to rear wall distance should be at least 30”. The above crossover works best at about 40”, but this of course is subjective as well as being influenced by room size-volume.
 
Crossover?

Is this the intended crossover?
If not, please remove this post.
 

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