The "Force 8" collaborative design

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Slightly larger 5" SEAS midrange, it has good sensitivity (89.5 dB/2.83V), put it in an enclosure that provides the same Fc as the original Peerless and you could probably use the original crossover - note the very smooth response:
SEAS Prestige MCA15RCY (H1262):
https://www.madisoundspeakerstore.c...ige-mca15rcy-h1262-5.5-coated-paper-midrange/

Alternate if you must have a 4", but it is significantly less efficient 86 dB/2.83V - probably not a good fit:
https://www.madisoundspeakerstore.c...tige-mca12rc-h1304-4.5-coated-paper-midrange/

Both of the above are true midranges with short VC wind height which is what you want since a mid crossed high does not need much throw.

The high crossover point makes a .75" tweeter a good alternative, add 2 ohm resistor to better match the original tweeter impedance:
SB Acoustics SB19ST-C000-4 3/4" dome tweeter, 4 ohms
https://www.madisoundspeakerstore.c...ustics-sb19st-c000-4-3/4-dome-tweeter-4-ohms/

If you must have a 1" tweeter, also add resistance as needed, this is much more sensitive and is probably a better match for the original:
SB Acoustics SB26STCN-C000-4 tweeter
https://www.madisoundspeakerstore.c.../sb-acoustics-sb26stcn-c000-4-tweeter-4-ohms/

I would use this tweeter if you want something closer to the original, this would be my pick:
ScanSpeak Discovery D2608/9130 1" Textile Dome HDS :
https://www.madisoundspeakerstore.c...covery-d2608/9130-1-textile-dome-hds-tweeter/

Get AR4 woofers, or perhaps these EPI 100 copies from Human Speakers:
HUMAN Speakers: PRO 001 Woofer

Note that they are 4 ohm so you could put them in series and then have an easy load.
Or use 2 of these 2 ohm versions in series for 4 ohms:
HUMAN Speakers: PRO 006 Woofer

Super size it and use a pair of the New Large Advent woofers, buy them used and refoam. The NLA woofers were very well made. You'd probably want 2-3 cu ft. Many ask for a 3way version of the Advent and this would be very impressive.

Simulate it, and make it even better than original.
 
For this "detour" design I have to hand a pair of potted Coral 5M-12, 8 ohm, 40W, 800hz-14kHz, plus a pair of Vifa D19TD-05-08, 8 ohm.

... and here is the prototype (mule), along with the bass driver donor.

The mule is made to the same external dimensions as the GS401A.
 

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Brisso some basic investigation on your Wharfedale drivers is in order here:

490142d1435141491-force-8-collaborative-design-image.jpg


What we got here? 4 or 8 ohm drivers? Wired in series or parallel? They look like those familiar old well behaved Elac units that work reflex or closed box.

The reason the Gale had such terrible low impedance was the 4" mid was being asked to go so loud and low. But if you wire the bass in series, it'll still be quite efficient if I know those Elac units. I expect 50-60L will be OK.

Really don't fancy that Coral cone mid, and flimsy D19 tweeter will need a highish 3.5kHz crossover. All you're doing really is building a closed three way with doubled bass units. A simple enough conversion.
ScanSpeak-3W-Discovery

Hi again System7
Well, for somewhere to start, I've tried this XO. (The Gale 3rd revision.)
RESULT: the mid needs to be padded a little more heavily. What values should I use to replace 6R2 and 3R9?
The mid is 8 ohm, 40W.

Thanks
Doug
 
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Having recently used it as a midwoofer I heartily recommend the FaitalPro 5FE120 as a mid here.
It's a 5" as the name suggests, 88dB/1W, 5mm Xmax and the response is flat out to 6k, takes 80Wrms, it is dirt cheap at £24ea and it sounds very, very good indeed.
It will easily keep up with a couple of 8" woofers, I'm thinking of pairing it with a 12" in a 3way.


I am also thinking of the FaitalPRO 5FE120 "fullrange" with a super tweeter above 5 to maybe 6KHz. Have you tried this by itself with no X/O? Even if not, would you say this might be the best "bang for the buck" 5 inch driver? I am also considering the Fostex Sigma series and the MarkAudio Alpairs (3 inch to 6 inch range; 4 1/2 inch to 5 1/4 inch prefered). Thanks for any further info, comments, etc.
 
Never tried the Faitals full-range, I cross them at 3.4kHz to a 19mm SEAS tweeter to minimize power response problems as much as possible with my driver choice.

Also can't say if they are the "best bang for the buck" 5" since I haven't tried all of them but I would say that they have a jolly good chance to be.
I like them better than the 5" Audax aerogels I've got in some other speakers and those cost 3x as much than the Faital 5FE120.
AFAIK the 5FE120 are the cheapest driver featuring demodulation which may have something to do with it.
 
Never tried the Faitals full-range, I cross them at 3.4kHz to a 19mm SEAS tweeter to minimize power response problems as much as possible with my driver choice.

Also can't say if they are the "best bang for the buck" 5" since I haven't tried all of them but I would say that they have a jolly good chance to be.
I like them better than the 5" Audax aerogels I've got in some other speakers and those cost 3x as much than the Faital 5FE120.
AFAIK the 5FE120 are the cheapest driver featuring demodulation which may have something to do with it.


OK, great! This helps; I have heard and used the Audax 4 inch aerogels and liked their sound "quality". Many people seem to like the FaitalPROs; I might eventually end up using a more expensive mid/full range driver but based on your input (and others); I will get a pair of the 5FE120s (very cheap price too!) and try them. Thanks!
 
I am also thinking of "fullrange" with a super tweeter above 5 to maybe 6KHz.

The Tang Band W5-2143 is a $60 full range worth your review for a high crossover frequency to a small diameter dome tweeter. W5-2143 has an underhung motor, very low Le, and a phase plug for some high frequency smoothing help. Mms =6g using Bamboo fiber and paper cone with santoprene surround. Good reviews.

The W5-2143 blends well with ribbon tweeters like the Fountek Neo X2.0.
 
I have resereccted this thread in the hope of getting some insight and advice as to how to move forward with a dilapadated pair of Gale 401c's I have. Under the Advice of System7 I re-did the crossovers. Anyone familiar with Gale 401's. So my Gales have 1 dead HF 2000 tweeter and 1 dead Peerless K040 Mid.
This thread has link to numerous mid/tweeter replacements, any advice on a tweeter/mid combo? I live in Australia so my purchasing power is limited. We have 'wagners online' which has some the SB acoustics, dayton, vifa, scanspeak and tympany. any help would be appreciated,
Austy
 
I have resereccted this thread in the hope of getting some insight and advice as to how to move forward with a dilapadated pair of Gale 401c's I have. Under the Advice of System7 I re-did the crossovers. Anyone familiar with Gale 401's. So my Gales have 1 dead HF 2000 tweeter and 1 dead Peerless K040 Mid.
This thread has link to numerous mid/tweeter replacements, any advice on a tweeter/mid combo? I live in Australia so my purchasing power is limited. We have 'wagners online' which has some the SB acoustics, dayton, vifa, scanspeak and tympany. any help would be appreciated,
Austy

483804d1431999040-familiar-gale-401s-gale-401c-restored-martint-jpg


483803d1431999040-familiar-gale-401s-gale-401c-crossover-png


Bit surprised the mid has failed. Have you tested it with a 1.5V battery or a meter?

How does the mid work? It has a little cup-like enclosure on the back doesn't it?

You might have to build an enclosure for a replacement. I should think 8 ohms is preferable. Get your measuring tape out. There are loads of good 4" mids and fullrangers around that might do. SEAS, MarkAudio, maybe SB if 8 ohms.

People seem to struggle with the SEAS 19TFF1 tweeter. IIRC, the HF2000 is a 100mm jobbie.
 
Just putting this Wagner Online link down for future reference:

Speaker Drivers | Wagner Online Electronic Stores

The 5" Peerless 830860 makes a good midrange by all accounts. The 4" 830870 might do too. Hmm, will have a dig.

A midrange driver is usually a specialist design though, different from a mid bass. Not built for big excursion and lighter and faster.
 
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Bit surprised the mid has failed. Have you tested it with a 1.5V battery or a meter?

How does the mid work? It has a little cup-like enclosure on the back doesn't it?

You might have to build an enclosure for a replacement. I should think 8 ohms is preferable. Get your measuring tape out. There are loads of good 4" mids and fullrangers around that might do. SEAS, MarkAudio, maybe SB if 8 ohms.

People seem to struggle with the SEAS 19TFF1 tweeter. IIRC, the HF2000 is a 100mm jobbie.
One mid was playing noticably quieter than the other, it has less excersion than the other as well. The tweeter was broken at the voice coil. I tried some surgery on it by unwinding a bit and reattaching but then it played poorly afterwards.
 
I think a bit of method and investigation is in order here, Austy.

You need to measure the working drivers for DC resistance to start. Use a multimeter on the bare drivers.

Looking at the schematic, one mid might sound louder if the 6.2R has gone open circuit. It really surprises me if one mid has gone quiet, unless they have AlNiCo magnets which can lose magnetic field strength over time. There is a specialist machine that can "Recharge" AlNiCo magnets

Does the little plastic cup come off the back of the mid? Just I am looking at a few of Wagner's radio speakers. The 4.7" GP speaker is 89dB and might do. Tweeter replacement shouldn't be hard, but it would be nice to get a similar plastic type.

General Purpose | Wagner Online Electronic Stores
 
The tweeter can be measured in situ, since I don't see a DC path there. Use 200R meter resistance or ohm setting and common and the adjacent socket.

If the meter is working right you'll get about 0.2R when you touch the probes together and about 6 ohms across the tweeter.

The mid is best disconnected at one point, because there are DC components in the crossover that will affect the reading.

Make notes of any wiring colours before disconnecting too much. Test all 4 mids and tweeters.

Wilmslow recommend these replacements:

Gale GS301, GS401, GS402

Treble unit - use Vifa XT19TD, Vifa D27TG or SEAS H831

Midrange - use Scanspeak D3806/820000

Bass - use Wilmslow WA-206 or Monacor SPH-210

Wilmslow Audio Ltd Repair and Upgrade Service

Surprising choice of midrange, and very expensive, but it solves the enclosure problem I suppose.
 
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