A new build with left over drivers and parts. I'm sure many folks would enjoy low cost build that sound great and play loud!
Started off as a rebuild of old boxes that was a DIY build from 20years ago, but the old boxes will full of nails/staples. Pitched that pair and started over.
The only salvaged parts are the PCV ports.
However, during the first attempt I did find a SF/Morel xo in Madisound's LEAP library.
The plan called out CAT-298 but I've been storing Morel MDT 28/30 since early 80s in hopes of project. Note that all the tweeter VCs do not have any ferrofluid left, evaporated I guess.
Ok then, built new boxes .75cf [net] fingers crossed I tried the old morels and was very happy with the measurements/results (3rd photo).
[the tweeter resistor was increased to 5.6ohm]
The woofers were on the shelf also, W20RC38/8, checked WinISD and used 2" PCV with router round-over bits. Fs tuning is in low 50s.
I also found that the 8" SF needs a 1lb of damping material and used the Blue Denim building insulation.
So far a no cost project, although I did order 900 units ferrofluid: guessing 4 5 drops should be enough for each tweeter.
* Morel - Bumble Bee speakers, they really shouldn't work lol I'll never forget reading that in a google search that took me back to DIY.
Started off as a rebuild of old boxes that was a DIY build from 20years ago, but the old boxes will full of nails/staples. Pitched that pair and started over.
The only salvaged parts are the PCV ports.
However, during the first attempt I did find a SF/Morel xo in Madisound's LEAP library.
The plan called out CAT-298 but I've been storing Morel MDT 28/30 since early 80s in hopes of project. Note that all the tweeter VCs do not have any ferrofluid left, evaporated I guess.
Ok then, built new boxes .75cf [net] fingers crossed I tried the old morels and was very happy with the measurements/results (3rd photo).
[the tweeter resistor was increased to 5.6ohm]
The woofers were on the shelf also, W20RC38/8, checked WinISD and used 2" PCV with router round-over bits. Fs tuning is in low 50s.
I also found that the 8" SF needs a 1lb of damping material and used the Blue Denim building insulation.
So far a no cost project, although I did order 900 units ferrofluid: guessing 4 5 drops should be enough for each tweeter.
* Morel - Bumble Bee speakers, they really shouldn't work lol I'll never forget reading that in a google search that took me back to DIY.
Attachments
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ODougbo, just when I was going to make a Damn Fool of myself with loudspeaker theories, along come you to inject some common sense. 
I do this sort of Morel CAT298 stuff sometimes:
Far better, IMO, is a cone tweeter:
Who knows where we are going during global meltdown due the wretched virus. I have Faith in London's greatest American Football bar. HOME | Passyunk Avenue
My advice is to just go easy on Philly CheeseSteaks with beer.
Happily the NFL have gone open on old games: YouTube
Nick Foles at Chicago?
Please God, Tom Brady doesn't come to Minnesota.
I do this sort of Morel CAT298 stuff sometimes:
Far better, IMO, is a cone tweeter:
Who knows where we are going during global meltdown due the wretched virus. I have Faith in London's greatest American Football bar. HOME | Passyunk Avenue
My advice is to just go easy on Philly CheeseSteaks with beer.
Happily the NFL have gone open on old games: YouTube
Nick Foles at Chicago?
Please God, Tom Brady doesn't come to Minnesota.
Interesting tweeter/cone speaker, and I'm sure they do sound better than the 1980s Morel...maybe someday.
Forgot to add the xo schematic, not sure how I even found it, it's over on Madisound's website - somewhere.
This was a quick easy build to return a favor to a buddy, just one coat of latex primer, will let that harden up for bit before sanding and re-coating.
The wife thinks they are cool and wants to put a pair in-between the columns separating the rooms.
Philly cheese steaks in London? say it ain't so.
Forgot to add the xo schematic, not sure how I even found it, it's over on Madisound's website - somewhere.
This was a quick easy build to return a favor to a buddy, just one coat of latex primer, will let that harden up for bit before sanding and re-coating.
The wife thinks they are cool and wants to put a pair in-between the columns separating the rooms.
Philly cheese steaks in London? say it ain't so.
Attachments
I had seen that one at Madisound:
W20RC38-8 + CAT298 2way Passive Crossover Design - Madisound Speaker PDF Library
I think we ended up in a similar place with a slightly different 8" woofer:
Your 5kHz LCR notch probably works better than my tank notch:
Many ways to skin a, er, CAT!
W20RC38-8 + CAT298 2way Passive Crossover Design - Madisound Speaker PDF Library
I think we ended up in a similar place with a slightly different 8" woofer:
Your 5kHz LCR notch probably works better than my tank notch:
Many ways to skin a, er, CAT!
Thanks, Steve, for that Stab from the Past- I lived on Ritner St, a few blocks south, near Cacia's Bakery.
We would walk to the Melrose Diner at 15th & Passyunk(pronounced 'Pa-shunk Street', tho an Avenue).
If you followed Passyunk on its diagonal northeast, past Broad St you would have Fiore's restaurant, then Pat's and Geno's, the famous dueling steak shops.
Turn east at Christian St for Isgro Pastry and amazing cannolis.
Then right on tenth into the Italian Market for all your cheese, produce, sausage, olives, pasta and sauce needs(the sauce at Talluto's made an Italian woman of my acquaintance exclaim "I want to have its babies!".
When you cross Washington Ave again, you will find Vietnamese restaurants.
Then it's a trolley car, bus, or cab and home to pass out from all your blood going to your stomach.
Some people know where all the watering holes are, I go for the food.
But I digress......sorry OP for the hijack.
We would walk to the Melrose Diner at 15th & Passyunk(pronounced 'Pa-shunk Street', tho an Avenue).
If you followed Passyunk on its diagonal northeast, past Broad St you would have Fiore's restaurant, then Pat's and Geno's, the famous dueling steak shops.
Turn east at Christian St for Isgro Pastry and amazing cannolis.
Then right on tenth into the Italian Market for all your cheese, produce, sausage, olives, pasta and sauce needs(the sauce at Talluto's made an Italian woman of my acquaintance exclaim "I want to have its babies!".
When you cross Washington Ave again, you will find Vietnamese restaurants.
Then it's a trolley car, bus, or cab and home to pass out from all your blood going to your stomach.
Some people know where all the watering holes are, I go for the food.
But I digress......sorry OP for the hijack.
I'm sure ODougbo doesn't mind as long as it's interesting! I will impress star servers Emily and Ash next time I see them in Cleveland Street with my improved pronunciation! Thank you.
I am quite the fan of the US, and have been to our Wembley for NFL with Da Bears versus The Bucs. Probably reading Raymond Chandler or James Ellroy on the train up. I like Noir. The Cops are crooked and the Femme Fatales have all the warmth of a Corpse. LOL
Brutal game, RB's Matt Forte and LeGarrette Blount both got season ending ACL injuries. People in the UK think NFL is a cissies game...
As it goes, John Wayne was a goodish football player too, but broke his knee. So was Ike Eisenhower. Similar injury.
Some very intelligent content here:
A history of Philadelphia in 10 dishes
I don't know what ODougbo snacks on in Baltimore. They must have something good.
AFAIK, the Cheez Whiz holds the sandwich together.
I am quite the fan of the US, and have been to our Wembley for NFL with Da Bears versus The Bucs. Probably reading Raymond Chandler or James Ellroy on the train up. I like Noir. The Cops are crooked and the Femme Fatales have all the warmth of a Corpse. LOL
Brutal game, RB's Matt Forte and LeGarrette Blount both got season ending ACL injuries. People in the UK think NFL is a cissies game...
As it goes, John Wayne was a goodish football player too, but broke his knee. So was Ike Eisenhower. Similar injury.
Some very intelligent content here:
A history of Philadelphia in 10 dishes
I don't know what ODougbo snacks on in Baltimore. They must have something good.
AFAIK, the Cheez Whiz holds the sandwich together.
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Not a terrible article, only got the meat-related details wrong.
The meat for a steak sandwich is never chopped, but shaved translucent-thin.
Hooves and hides make gelatin and glue.
Scrapple is essentially a broth-based polenta, chilled and fried.
Pig's heads, turkey carcasses, any meat or gristle-bearing bones are cooked to make a broth, flavored with sage and black pepper.
You remove the bones, chop finely any bits of meat, and add cornmeal.
Thicken and pour into loaf pans.
Chill.
Cut into pound or half-pound pieces and freeze what you won't use soon. Slice 1/4 to 3/4 inch thick and gently fry in veg or meat fat till crusty.
Eat with eggs with runny yolks, use toast or fresh bread for a shovel.
I had better stop now, I have only two packets left from the post-thanksgiving turkey batch.
The meat for a steak sandwich is never chopped, but shaved translucent-thin.
Hooves and hides make gelatin and glue.
Scrapple is essentially a broth-based polenta, chilled and fried.
Pig's heads, turkey carcasses, any meat or gristle-bearing bones are cooked to make a broth, flavored with sage and black pepper.
You remove the bones, chop finely any bits of meat, and add cornmeal.
Thicken and pour into loaf pans.
Chill.
Cut into pound or half-pound pieces and freeze what you won't use soon. Slice 1/4 to 3/4 inch thick and gently fry in veg or meat fat till crusty.
Eat with eggs with runny yolks, use toast or fresh bread for a shovel.
I had better stop now, I have only two packets left from the post-thanksgiving turkey batch.
I'm originally a Philly guy,,,still hang out with some of my old friends up there - actually this project started out for one of them.
There's a sandwich shop right over the PA line in Delaware - Claymont Steak Shop, they cook steak mounds at a time, so much beef you may consider going Vegan when you see it..lol
But I digress, I have been working on this since the wee hours of the morning, rebuilt one of the boxes with a few upgraded xo components and serviced the morel with the Ferrofluid.
A step in the right direction!
There's a sandwich shop right over the PA line in Delaware - Claymont Steak Shop, they cook steak mounds at a time, so much beef you may consider going Vegan when you see it..lol
But I digress, I have been working on this since the wee hours of the morning, rebuilt one of the boxes with a few upgraded xo components and serviced the morel with the Ferrofluid.
A step in the right direction!
Sat down a couple of days ago and listened to three of my favorite CDs,,,bla changed my mind on the tweeter replacement. There is a impedance rise that is producing sour notes at certain frequencies. I bet the morel would work better with a simple cap xo. But chose them because they were the smallest and would be easy to swap out by enlarging the cutout.
I did get hooked on the 8" SF in the 10" x 17" box, it sounds like 8" woofer in a 2.0 cubit foot box. With the heaver baffle step coil used only 1/2lb of the blue denim.
Well not ready to break them down yet, just made a new box similar to the old PE boxes with the removable fonts. They [PE] used to bevel-cut the rear of the baffle which helps seal the box, this does seam to work. Used a raised door cabinet cutter for the profile.
New xo, I'll start with this, two crossovers from other projects with similar drivers.
I did get hooked on the 8" SF in the 10" x 17" box, it sounds like 8" woofer in a 2.0 cubit foot box. With the heaver baffle step coil used only 1/2lb of the blue denim.
Well not ready to break them down yet, just made a new box similar to the old PE boxes with the removable fonts. They [PE] used to bevel-cut the rear of the baffle which helps seal the box, this does seam to work. Used a raised door cabinet cutter for the profile.
New xo, I'll start with this, two crossovers from other projects with similar drivers.
Attachments
Just another 2-way
Well was side tracked a bit but assembled/tested the xo from the last post.
I think its fine and on the 1st attempt (lol after many, many other dud speaker projects)
Thinking the morels I have laying around are mismatched, but the xo was wrong anyway.
Well was side tracked a bit but assembled/tested the xo from the last post.
I think its fine and on the 1st attempt (lol after many, many other dud speaker projects)
Thinking the morels I have laying around are mismatched, but the xo was wrong anyway.
Attachments
IIRC, Morel tweeters need some unsoldering to sort out any dried-up ferrofluid. Which just turns to sticky sludge after many years. Killing the output.
But I would be checking them for that if ancient.
I'm having a good time with my current effort:
I ditched the 0.47uF/22R tank notch. They are a dubious fix IMO.
I don't see much wrong with the bass filter for your flutes with the LCR notch.
What transforms the speakers is a grille cloth, IMO.
The ancients used to use some cloth with a bit of spongey foam added. Maybe they knew something. The return of the smooth!
But I would be checking them for that if ancient.
I'm having a good time with my current effort:
I ditched the 0.47uF/22R tank notch. They are a dubious fix IMO.
I don't see much wrong with the bass filter for your flutes with the LCR notch.
What transforms the speakers is a grille cloth, IMO.
The ancients used to use some cloth with a bit of spongey foam added. Maybe they knew something. The return of the smooth!
Thanks for the morel tips and your design, never would have thought to do a complete over-haul, unsoldering and then cleaning. I'll have to make a board with cutouts and attach a few for testing, to check for a matching pair.
I remember back buying all these morels, most sounded clear as a whistle, whereas a small percentage had a secondary tone/buzz. Never did figure that out.
[Replacement VC's are available for $27]
**
W20RC38/8 and SB29RDC Budget Build
Another marathon day yesterday, complete overhaul of the gray-primer mdf boxes: replaced the tweeters, added bracing, retrofitted the xo's and tested.
The 8" woofer is musical and has wonderful bass (with the PE P-core baffle step coil). Used a 6.8ohm resistor for the tweeter.
Both speakers here:
Checking out the CDs - nice!
I remember back buying all these morels, most sounded clear as a whistle, whereas a small percentage had a secondary tone/buzz. Never did figure that out.
[Replacement VC's are available for $27]
**
W20RC38/8 and SB29RDC Budget Build
Another marathon day yesterday, complete overhaul of the gray-primer mdf boxes: replaced the tweeters, added bracing, retrofitted the xo's and tested.
The 8" woofer is musical and has wonderful bass (with the PE P-core baffle step coil). Used a 6.8ohm resistor for the tweeter.
Both speakers here:
Checking out the CDs - nice!
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