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All British 3-way Open Baffle HELP thread

Poultrygeist said:
It's active but you must build two plus provide your own power supply. Boozhound sells populated active crossover boards.

All active crossovers are upstream of the amp which means the signal is divided before it's amplified and that's a major advantage.
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Thanks Poultrygeist....I'm kind of new at this.

Just to kibitz....In a tri amp setup. Each amp would only get and output say low or mid or high frequency. Why is that a major advantage?

If I used a vintage tube amp for each one....would there be any "burn in" or cause any problem for the amps....as they would only be dealing with a part of the whole audio frequency?

Am I totally wrong about this..? Is it only a question of millivolts and not frequency?

I suppose I could (if I ever get a tri amp up and running) switch the amps around once in a while...to let them work with a different frequecy,

Yes, you are right...I'd need two of those.

I'm a noob......don't know the lingo...or the theory.
 
Active crossovers are often called frequency dividers as that's what they do. An active allows mixing flea amps and powerful amps in the same system.

It can be confusing as we aren't used to putting a device between the preamp and power amps.

These articles are a good resource regarding active vs passive, bi-amping and tri-amping and the advantages of active ( electronic ) crossovers.

http://sound.westhost.com/bi-amp2.htm#tri-amp
 
NOTE: I did not say "Box" I said "frame".. open backs. As you mentioned the wife might insist, You can get thin sheer elastic material at fabric shops stretches perfect. I was thinking that if you want to place them for a while or tuck them out of the way.
 
Binkman said:
NOTE: I did not say "Box" I said "frame".. open backs. As you mentioned the wife might insist, You can get thin sheer elastic material at fabric shops stretches perfect. I was thinking that if you want to place them for a while or tuck them out of the way.
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Hi Bink,

Thanks, "frame", duly noted. Will consider all options (esp. for WAF)! :yes:

In the mean time, I'm still trying to dial these in.
 
Well, update.....

So I've hooked up my Behringer CS2310 and, no sparks or smoke!

As per PG's suggestion, I'm splitting the 2 amp signals between the LF and the full range (mid) plus the tweets. Fun to play with the crossover. 300 seems to really work!

I took out all of the passive crossover except the 4uf cap to the tweets. But in order to get my fat bass, I have to attenuate the RA CG10T's a fair bit. With the tweets on the same signal, I'm losing much of my beloved HF sizzle. (What I can hear of it, with my 12KZ max hearing range.) So I put the L-pads back in for the RA's only. Push them a bit further back, and gets my brightness back. So...., progress!

But one of my Super 3 tweets appears to have crapped out. :tears: Damn!

As a stopgap, I've attached Magnavox (Hepner) mid horns to the back of the baffles firing upwards. Pretty interesting. Pretty sure they're 16 ohm, and with just the existing 4uf cap, they're crossing at about 2500. Way low. I understand they could cross even lower, but I don't need to supplement the Richard Allans. Just pick up from about 7Kz on up. I understand these roll off at about 15Khz, but that's above the top of my range anyway. Going to look at about 1.4 caps, for high pass at 7000.

Pics later. It's always something!! :scratch2:
 
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Post Relocation Update

So, my wife and I moved about 80km (50 miles), to be closer to the grandson (in February!).

Anyway, it's taken a little while to get things sorted out. After setting up the W90s in the living room (both pointed the same direction for the first time!), I turned my attention to the basement OBs. Hence the update:

They still look like mongrel dogs, but they really do sound nice to my ears. I haven't put any legs or framing on the baffles. Just put some pipe insulation on the bottom edge for friction against the table surfaces, and guy-wired them to the ceiling joists. That keeps them moreorless vertical, and gets them away from the wall a little.

Some pics-

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That's from across the room.

The ones below show the current source setup. An Airport Express streaming high bitrate MP3s into my 80's Rotel serving as a preamp. From there into the Behringer, then out into 4 channels of the Adcom GFA7500.

A few more pics to follow.
 

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A few more pics...............

Each baffle, and an exclusive " behind the scenes" pic showing the upfiring Maggie horn (tacked to the upper edge of each). The Wharfedale Super 3s are just dead weight sadly.

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Nice...Did you do the driver openings with a jigsaw? My first pair of speakers used 8" Saba Greencone Mids, and the openings had to be covered in some areas with carton, yours don't have gaps though.
 
Yup, jigsaw...freehand. I drew the openings with a compass, just didn't follow the lines very well. Only afterward did I find my (lost) circle jig for the saw. I'll eventually do up new better baffles, and borrow the son in law's router (with jig).

Not sure I'll ever convince my wife these are ready for the living room, so the WAF pressure isn't a factor for now. Instead I'm just enjoying the sound!
 
Hi PG!

Yes, a very fun project. Thanks to active bi-amping, I've applied maximum EQ to the woofers. With the Richard Allans and the Maggie horns dialled way back.

I'll actually be backing off the bass a little bit. I'm crossing over at 700Hz, and my wife tells me that my OBs are "too" bassy.

The B&W DW13 woofs were said to have free air resonance of "18-22Hz"(!). I don't think I need a sub.............:D
 
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You won't need a sub unless you want to feel visceral impact which I'm not sure is music or room rumble at those levels. :D
 
Further little update......

So I guess this is becoming a "members' system thread.

Anyway, I dug out my H/K 730 rig (with amp issues), and put it into service as my preamp. Much nicer than the Rotel. That one has always seemed a bit congested and rolled off (and my hearing's gone much past 12KHz!). I've read that pre in the 730 is considered a little less highly than the amp section. Oh well, sounds nice to me.

Likely my unfinished basement "listening space" is a limiting factor in my audio journey right now. That's where biamping with the 150wpc adcom comes in handy. I understand that an amp can't remedy a source, but a little brute force to the LF drivers generates some sweet OB music to my ears. :music:
 
PioneerGuy75 said:
Those look cool.

Interesting idea with the up-firing horn....:scratch2:

:banana::banana:
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Thanks, I ripped off Gilbert Briggs's upfiring idea (in his Wharfedale SFB3) design. Plus, it was the easiest way to attach the horns.

I've since replaced them with little Foster bullet (horn) tweets, mounted in the baffle facing forward. A bit more sparkle. :tresbon:
 
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