New Rectilinear III lowboy recap

Wasn't me, I haven't lived in the 'burgh in almost 20 years, although I'd love to move back. Hopefully it was someone who will appreciate them ('n' 'at)

I felt bad when I picked up these lowboys, I threw out an offer that I thought was kind of lowball but was what I could afford (e.g. nothing ventured, etc.) and sure enough the nice young lady selling them said they were her dad's speakers and they needed to go because they were too big... but then she ruined it by saying that she had fond memories of them and I felt like kind of an a-hole, but apparently there was just no space for them. I made sure to drop her a note and let her know that the wood cleaned up nicely (there's still a water spot on one, but it's not that bad - the Beam Box covers it) and that I was going to recap them and use them as the main speakers in the living room to hopefully ease the pain a bit. I don't know if telling her that they'd be replacing a pair of Wharfedales helped or hurt.

Oh, yeah, I picked up a Beam Box FM-10 yesterday for a decent price... eBay seller had $25 shipping on it so that killed the non-local bids, but I met the guy in the BB parking lot right on my way home. This really is going to be a pretty decent 70's system when it all comes together. I got a FM-8 with my Luxman receiver but I'm still gluing it back together - it was one good knock away from becoming a pile of pressboard, and all the "veneer" is peeling off of it. I guess that can go in a bedroom when it's done to get rid of a dipole.
 
Thanks Biggles, ordered. Unfortunately I can't say when I'll actually get to hear these things in their glory as apparently I just got a huge steaming pile of work dropped on me (you know, the stuff I'm paid to do, not the stuff I choose to do) and I dropped my Luxman receiver off to be repaired yesterday, but baby steps, right? I agree that probably even new 'lytics would be better than what's in there, but I'm a big fan of fixing something once. $50 in caps kinda hurts when I already paid for the speakers, but I'm hoping that this pays off in the end.

Any forward progress is progress in the right direction. Hey, I just purchased the caps for the Leak 2060's. That brother man, was painful! I decided to just go for it, my work is going to dwindle out here as soon as the cold weather hits. Get it done while I can, ya know. 2 of the caps are 75uF, about big around as a silver dollar, maybe more.

Yay! Another Rec III thread! I always love seeing these revived. When I rebuild my highboys, ( http://audiokarma.org/forums/index.php?threads/rectilinear-highboys-can-i-fix-them.541919/ ) I used a 50uf electrolytic and a 10uf poly, to replace the 60, and a 2uf poly for the other, all from Parts Express. They sound great to me. It seems to be the consensus that these speakers really come alive with a recap. In fact, I find it hard to imagine wanting anything else out of a speaker.

My crazy carpet grill cloths were pretty beat up, so I got black speaker cloth from Joanne Fabric, and love it. I always listen with them on though. Maybe I should try off sometime...
Here's a pic of that black cloth.

Hey man, nice III action! They don't so much come alive with a recap as they get back to the way they were originally intended. Congrats!

Biggles
 
So my care package from Madisound showed up yesterday, fortunately I expected the 60uF caps to be enormous so had hot melt glue gun ready :) (just glued them to the back of the cabinet right below the xover plate)

what a difference! Before I was running them with the pots all the way up and a both midrange and treble up a little at the receiver and bass one click down... now with everything flat I still think they sound better. Unfortunately all I had time to do last night was to get the speakers back together and roughly tested and make dinner... one of those weeks at work...
 
My crazy carpet grill cloths were pretty beat up, so I got black speaker cloth from Joanne Fabric, and love it. I always listen with them on though. Maybe I should try off sometime...
Here's a pic of that black cloth.
Gotta jump in here to say those look pretty sharp! My III's have the same grille cloth yours had. Nice to see the house plant is on the bookshelf and not on top of your speaker. Is that little sculpture thingie a plant ward speaker-saver?
 
Dang! You're cooking right along, niiiiice. Yeah, it is kinda fun to be able to knock the pots back a bit. You feel like you have a little more control and you're getting all you can out of the drivers.

Biggles
 
I know you've already purchased your caps but for some larger value caps, I have found motor run caps to work well. Modern versions are polypro in oil. I think they are smoother than some other caps and yet still nicely detailed.
 
I thought about that... I know some people swear by paper in oil, didn't know if modern motor run caps would sound as nice or not. In any case I'm certain that just getting one close to spec is 90% of the battle.
 
I've got a load of modern motor run caps set aside for the Wreckedilinears, just for fun. I've been using oil caps mostly for older paper cone tweeters/midranges and horns. Sometimes modern film/foil caps can make them shreaky, shouty. I was kinda wondering what the oil caps would do for the more "modern" drivers in the III's.

Biggles
 
I was kinda wondering what the oil caps would do for the more "modern" drivers in the III's.Biggles

I've only used them on modern tweeters, i.e., a nice Scan Speak silk dome in some DIY speakers. The design is by Lynn Olson from the Nutshell Hifi web page, the Ariels. I used Solens initially and for about a year I could never get over a sort of glare when the volume was a bit louder. I thought is was my ears going old. Got a couple of motor runs for the tweeter series caps and the glare disappeared. It's not what I expected (I tried them for other reasons) but I was delighted. I bought them from Grainger, but there are many good deals on the big auction site.

John
 
I've only used them on modern tweeters, i.e., a nice Scan Speak silk dome in some DIY speakers. The design is by Lynn Olson from the Nutshell Hifi web page, the Ariels. I used Solens initially and for about a year I could never get over a sort of glare when the volume was a bit louder. I thought is was my ears going old. Got a couple of motor runs for the tweeter series caps and the glare disappeared. It's not what I expected (I tried them for other reasons) but I was delighted. I bought them from Grainger, but there are many good deals on the big auction site.

John

That's really good to know. I'm not having any glare issues in either of my III's. I probably couldn't hear it anyways. But my 20 year old son certainly could and he hasn't said anything. And he most certainly would if it was there. I was listening to a burned CD a week ago and he walked through the room and asked me why I was listening to such a poor copy. Said he heard the midrange warble in the digital version. He laughed at me and suggested I should at least listen to a cassette. Egads man, what have I created?

In any case, thank you again for the heads up on real modern drivers and oil caps.

Biggles
 
On at least one Rectilinear model, they claim that the grill cloth used helped to improve the tweeter dispersion. On earlier these models I see 2 different colors, beside the off-white used on the very earliest model.

If you make a lattice-less grill assembly, it might be advantageous to place a horizontal rib outside the cloth in the space between the woofer bottom area an the mid-range area (a little more than half way up). Shouldn't make it look bad and can stabilize the grill cloth.

I am able to enjoy mine with the mid control at 1200 and the treble at about 130 - not wild about West Coast sound. But I get too much sound from lower mid likely due to old caps. I plan on recapping mine with juat NPEs as per original design. I might test the old Temple caps just for curiosity; values might have changed or not, I don't care.
 
yeah, I am still undecided exactly *how* I am going to do this... was thinking maybe MDF, if it can be found thin enough, with cutouts for the drivers done with a jigsaw. Alternately, a frame fabbed from some kind of thinner material, although the only thinner materials I can think of are things like Masonite and plywood which are hard to find staples that won't poke through. Guess the real deciding factor is how far the baffles are recessed from the case, and I have not measured yet. If less than 3/4" then no problem with either MDF or 1x? soft pine.
I need to find some free time to go shopping and actually look into this. As it is now I'm listening with no grilles and enjoying them. Well, actually I'm at work, but when I do listen to them, the grilles are off...
 
Hey,

I used 1/4" plywood for my III's. I don't know what the tolerance is for the Lowboy version. The reason I opted to use plywood was the cost versus MDF. Not that it's a lot to begin with, but sometimes money can be tight around here. The major issue with plywood is that the edges tend to chip and wood pulls off in tears. When you wrap cloth over plywood with those types of tiny chunks missing, is that it shows up clearly through the cloth. And, you can see it from across the room. Of course with black cloth, this probably won't be much of an issue. Sanding the edges only helps a bit. I ended up having to use wood filler to fix mine. But since I made those, I picked up a nice portable table saw and jagged edges from previous attempts are no longer an issue.

Staples are not required to hold down grill cloth. I've got about 3 or 4 pairs of speakers out there where I used 3M 77 adhesive spray only. On one project, I had to pull the cloth off the frame that I'd used 3M's product on. It adhered so well, not using staples didn't worry me a bit.

Biggles
 
I think both I and the design department are thinking of a light colored cloth a la AR3 kind of thing. But that is of course not going to be decided until I actually find time to make something to hold the cloth...

Did you paint the plywood flat black before putting the cloth on it?
 
I think both I and the design department are thinking of a light colored cloth a la AR3 kind of thing. But that is of course not going to be decided until I actually find time to make something to hold the cloth...

Did you paint the plywood flat black before putting the cloth on it?

Hey,

The face and the edges both outside and driver holes were painted black. The backs were left unfinished. So far, I haven't received any negative comments from anyone poking around. I left the backs unfinished so the adhesive would have something decent to stick to.

When using the 1/4" plywood and using 1/4" staples, I have been successful in getting the velcro into place. I use a dab of Amazing Goop on the velcro along with staples to hold it in place. 3 weeks ago, a friend gave me a 16 piece set of special drill press bits (made in Austria in a wooden box). They cut holes so they're flat and perfect, not like a spade bit. I'm hoping my next grill frame project I'll be able to use rare earth magnets, that would be awesome.

Biggles
 
I know you've already purchased your caps but for some larger value caps, I have found motor run caps to work well. Modern versions are polypro in oil. I think they are smoother than some other caps and yet still nicely detailed.

On one of my pair of Highboys, I'm using motor run caps for the midrange, Russian PIOs for the tweeters, and air core inductors for both.

Come to think of it, there's nothing left of the original crossover. Oh, and I replaced the Philips mid with a Tang Band bamboo 4" midrange. And completely rewired them, and mirror imaged the front baffles. And refinished the cabinets, new grille cloth, built custom stands, added new fiberglass stuffing, and installed rear firing tweeters.

other than that, they are 100% original. Next up I need to work on my Lowboys.
 
That is very generous John and I might just take you up on it at least for rough cutting... Digging my roommates table saw out of the shed just for a few cuts is a PITA. But right now what I'm short of is time :/
 
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