longdrive03

A friend commissioned me to build a replica cabinet of this vintage speaker (to slightly different dimensions). First pic shows the speaker as built. Second pics show my progress so far. Third pic shows rear of WE753 (using 15" woofer). Dimension on 753 were 30" tall, 20" wide and 14" deep. This build is 30" tall, 24" wide and 14" deep. He is going to place these in an opening in a wall cabinet. The grill (top, bottom and slats) are solid walnut. The sides will be 3/4" BB ply with a 1/2" ply panel veneer on top with curly walnut veneer. I used walnut edge banding to hide the ply edges on 1/2" ply panels. Top is figured walnut veneer matching up with the back of the front top piece which is solid walnut. My friend is using a 12" Altec 601C woofer (he had it reconed at Great Plains Audio) and GPA driver on a mid/tweeter horn (horn bends downward to allow shallow cabinet (14" deep).The grill was a chore to get right. The motorboard is installed through the removable back with brown cane type grill material. He will use an EV electronic crossover. Cabinet is vented.I'll post as I proceed.

Is this what you need?? I've got black and red with washers and nuts. PM me.

John, Here is a link to a CL listing here in Arkansas. Seller has one H-700. He has listed this numerous times. I am not the seller, don't know the seller, and have no financial connection with the seller. Might check it out. Hope that helps. https://littlerock.craigslist.org/ele/6173164427.html

All depends on the turning of the waters with the vent diameter and length. I'm assuming the workers or eight home and wired in parallel on both sets

If Klipsch doesn't help you let me know. I've got tons of these and will send for free. Thanks

We need to know what woofers you have and TS specs.

I understand (from HDBR -ex Klipsch employee) that the LSII only used 1" mdf on the sides, top and bottom of the bass bin and the doghouse is still 3/4" as in the LS. I don't recall if the back board is 1" but don't think it is. HDBR can probably answer that. I just finished a set of LS using 1" BB ply throughout and had to make adjustments. If what I said above is correct you can just add 1/2" to the width of the bass bin and mid/high top (keeping the same internal dimensions of the bass horn. I assume you will use 1" thick ply/mdf on the top section to match the bass bin ?

Pat, I speak from experience with the MCM 2953 driver. Go to the website and scroll down the reviews and you'll see my review that the pair I got were WAY OFF on specs. Not even close. QUT was like .7??. (I think I made a type on the spl I measured it was nowhere close to their published specs). At that price QC can't be extremely high. I've had 12" MCM woofer that had the same problem. Hope this helps.

Thanks guys. CEC I'm not sure on your question but maybe some technical guys (above my level) can address that issue. I know that they sound very good (I think they are smoother than the RF7ii set I built even though they use the "old" K-67. This one seems better balance without the sometimes shrill sound of the RF 7ii. Could be room size/placement other factors as well. But I really enjoy this speaker.

A friend of mine bought a group of speakers including two RC7 center channels in black paint. I am building new cabinets and arranging the woofers and tweeter in a WWT alignment with the top woofer crossed over at the higher crossover point. The cabinet is a little larger (32" H x 11" W x 11" D) Finished one and started on the second. I used birdseye maple veneer and white grill cloth at the request of his wife. Turns out that it looks pretty good even though I had my doubts about the white grill cloth . I did the "DeanG" 2ohm resistor switch to 1.8ohm on the tweeter series notch filter. Man they sound sweet.

Thanks No. 4. Ready to move on to something smaller and lighter now.

Sure add pics. That will help

Okay, the second one is done except for installing mid, tweeter and crossover and stretching brown cane grill cloth (owner will do that). These babies are 200lbs at least. Ready to work on next project - taking components from two RC7 and putting in WWT alignment in new vertical cabinet with birdseye maple veneer. Much easier.

If you want to go to the effort the neo magnet system works great. You would either have to drill through the mid/tw motorboard to recess the magnet (which would show unless you veneer over it or you could drill in from the back making sure you don't punch through and epoxy in the magnets from behind ( I know this is hard having don't it!) If you use magnets I would suggest the 3/8" magnets sold by Madisound for 65 cents each. They are very strong. Good luck

Update. About to wrap us second LS. Hope it looks like the first one!!!!. I have decided that I can drop my health club membership and just lift big chunks of 1" BB plywood instead. May that stuff is heavy and hard to grip. These are coming along and hop to have top attached and veneer on outside panels and solid front trim done this weekend. I'm ready to go back to simple rectangular speakers for a while!!

SB, bases look great! I like your engineering on these. Does make a difference to point the tweeter and mid up a bit. Doesn't help to have the tweeter firing at your kneecaps. Great job.

The flat black except V portion would look good. The bottom and top of the bass chamber is the hardest to cut and apply. The length should be 22.25" on the bass bin innards. Might be easier to apply the bottom and top cutouts first with a tiny gap around the edges and then install the 22.25" tall vertical pieces in between the fill in the tiny gap. This is just me thinking and I've never done it but I know from experience you can wast a whole lot of veneer by make a small mistake!! Could the cotton balls be there on purpose to tame the horn harshness. I thin Moray James suggests using a foam ball or tissue in the mid horn to tame harshness. Good luck.

Bama, I've never veneered a LS that was intact. Boy you have to cut the veneer exactly right. A lot easier what I'm doing now building one from scratch and veneering as I go. The separate doghouse should be easier since you don't have to worry about the length of the veneer. Post pics of whatever you decide to do. Great project.

Congrats on your redo project. Many happy hours of listening ahead!

Man, what a great project. You can do about anything you want at this stage. The guy could have installed the brace inside the doghouse through the hatch using some glue and two screws. At this stage all the hard work is done. You could paint them black inside and veneer the outside. Great steal!!!!

Okay I may tinker with fitting an adaptor to the horn when I finish the current LaScala build. Might sound good mated with a 15" woofer.

I understand the version 1 CF4 had a 5" port and version 2 has a 2.5" port. I have read where the version 2 crossover was modified to allow for the shorter length port. Does anyone have info on this or perhaps a schematic or pics of the two versions?

Seti, great idea. May try that. Have to do some fancy routing to match that baby up.

Here you go. The 120856 unit is no longer available and has been replaced by the 120841. I just measured one unit. ;------------------------------------------------------------------ Re = 6.2688 ohms Fs = 60.4651 Hz Zmax = 67.5398 ohms Qes = 0.5583 Qms = 5.4566 Qts = 0.5065 Le = 0.8305 mH (at 1 kHz) Diam = 165.1000 mm ( 6.5000 in ) Sd = 21408.3884 mm^2( 33.1831 in^2) Vas = 20.7501 L ( 0.7328 ft^3) BL = 9.6301 N/A Mms = 21.7391 g Cms = 318.7046 uM/N Kms = 3137.7019 N/M Rms = 1.5136 R mechanical Efficiency = 0.7720 % Sensitivity= 90.8944 dB @1W/1m Sensitivity= 91.9535 dB @2.83Vrms/1m Krm = 396.683E-06 ohms Freq dependent resistance Erm = 936.956E-03 Rem=Krm*(2*pi*f)^Erm Kxm = 14.262E-03 Henries Freq dependent reactance Exm = 673.214E-03 Xem=Kxm*(2*pi*f)^Exm ;------------------------------------------------------------------ Ftest = 46.512 Hz Ftest/Fms = 0.7692 Test Mass used = 15.0000 g (Equal to 3.0 nickels) Test Mass (Ft=Fms*0.90) = 5.099 g (Add -9.901g for Ft=54.419) Test Mass (Ft=Fms*0.75) = 16.908 g (Add 1.908g for Ft=45.349) I don't think this would work very well in a folded horn subwoofer. I don't know the xmax but it isn't much and the Fs isn't low enough.

Doc, I'm about to take two RC7 CC and make a pair of front speakers for a friend. I thought I had the TS specs but don't so I'll run them if my PC works right using Woofer Tester II and let you know. I can tall you the two woofers are not 98 db - maybe 93.