Fast, fun, Inexpensive OB project

[jerome69]

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.

[tyee]

Hey John
Can you post a pic of the latest and greatest crossover for the D3806 that your using!! I have the drivers, just need to build the best crossover.

[John Bsuch]

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.

[Pano]

I'll try to draw the crossover. It's complicated, so I'll need you help, John.

[nicoch58]

Large domes

the ciare 320, not bad

[teamacc]

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

[Pano]

That looks right to me. John?

[John Bsuch]

Teamacc..

Great job, your schematic is correct. Thanks for taking your time to post.

John

[teamacc]

Paintskills ftw...

I would love to try the OB, but im seriously underfunded right now.
Just bought 2 NOS mission 760i. Never used. Original packaging

[sagamotto]

just curious, but will the hi vi S1 coax mid+tw work with this project?