DCM TimeFrame TF-700, crossover problem

I'm restoring a pair of DCM TimeFrame TF-700 speakers, and need help with the crossover...

my crossovers have been mucked around with, and I'm trying to get them back into correct factory configuration ity:ity:ity:

cannot find a schematic for the TF-700, only for TF-1000... apparently, the only difference between TF-700 and TF-1000 crossovers is that resistor RA is 47 ohm in the TF-700 (vs. 100 ohm)... this is not 100% confirmed

please note I believe I have a pair of *first generation* TF-700s because:
- terminal cup is small, round 3" diameter (not large rectangular)
- crossover is crudely hand-made on a piece of scrap wood with messy point-to-point wiring (not nice and neat on a custom PCB board)

otherwise, my understanding is that the first and later generations of TF-700 used the exact same drivers and crossover values, so should otherwise function and sound the same

QUESTIONS:

Q1: does anyone have an actual TF-700 schematic?... do they even exist?
Q2: is it true that TF-700 and TF-1000 crossovers are the exact same (except for RA)?
Q3: TF-1000 schematic shows presence of a resistor R1 (15 ohm, 2W, 10%), but THIS PART IS MISSING FROM MY CROSSOVER!!!... can anyone confirm that R1 is supposed to be there based on experience with your TF-700s?... if so, is your R1 value 15 ohms? (any pics greatly appreciated, especially showing R1's location)
Q4: is there a chance that first generation TF-700s did not have an R1?

any help greatly appreciated, thank you!

ATTACHED PHOTOS:
- schematic for the TF-1000 (not TF-700)
- my crossover (AS FOUND with some part swaps but no apparent wiring changes)

MORE INFO:

I've searched the web for unmolested TF-700 crossovers photos... so far, I've turned up *3* different types:

Version A: handmade tangled mess on a piece of wood (like mine, probably first generation)... total of 5 resistors, maybe 6? (hard to tell if resistor R1 is present, but so far I don't see any)
Version B: sleeker PCB style, with R1 present with 15 ohm value (sitting right beside C1)... total of 6 resistors
Version C: sleeker PCB style, with R1 present with 47 ohm value (sitting right beside C1)... total of 6 resistors

now I'm really confused!... seeing as the TF-700s all have the same drivers, shouldn't the crossovers be the same?... perhaps I should add in R1 to bring mine up to date with the later versions?... if so, what's best value for R1: 15 or 47 ohms?

I never worked on one of the first generation TF-700's although I own a pair. Never had to open mine up. I have worked on the newer ones and they had a PCB for the crossover. The way to tell first generation is the body stocking does not cover the back of the speaker. It is tucked in under the back panel. I think I may have a schematic, I will look.

"VERSION A" crossovers (that I found on the web, apparently from TF-700s)... this is the type I have, AKA "first generation"

a total of 5 resistors... a sixth might be hiding?, but probably not since mine are missing this one also

"VERSION B" crossovers (that I found on the web, apparently from TF-700s)

value of R1 is *15* OHMS

a total of 6 resistors... suspected location of R1 shown as per my drawing

"VERSION C" crossovers (that I found on the web, apparently from TF-700s)

value of R1 is *47* OHMS

a total of 6 resistors... suspected location of R1 shown as per my drawing

and finally here's an unknown... either VERSION B or C, but can't see the resistor to be sure:

ssouci said:

"VERSION B" crossovers (that I found on the web, apparently from TF-700s)

value of R1 is *15* OHMS

a total of 6 resistors... suspected location of R1 shown as per my drawing

Click to expand...

SSouci, the 3rd and 4th pics you've attached are from my TimeFrames. In my case, both the TF700 and TF1000 have nearly identical crossovers. There is only a very small difference in the value of RA on the schematic for the TF1000 (47 ohms vs 100 ohms). Beside that all cap, resistor and coil values are identical. They're even mounted on the same board.

I don't think the earlier versions had the same number of resistors. If you're wanting to rebuild your crossovers, use the same number and values that yours came with (first gen?).

If I'm not mistaken though, all of the TF700s use the same drivers as do the TF1000s.

ssouci said:

and finally here's an unknown... either VERSION B or C, but can't see the resistor to be sure:

Click to expand...

That's mine too. I had snipped the wire on the 47uF capacitor in order to read its value.

Dr. Morbius said:

SSouci, the 3rd and 4th pics you've attached are from my TimeFrames. In my case, both the TF700 and TF1000 have nearly identical crossovers. There is only a very small difference in the value of RA on the schematic for the TF1000 (47 ohms vs 100 ohms). Beside that all cap, resistor and coil values are identical. They're even mounted on the same board.

I don't think the earlier versions had the same number of resistors. If you're wanting to rebuild your crossovers, use the same number and values that yours came with (first gen?).

If I'm not mistaken though, all of the TF700s use the same drivers as do the TF1000s.

Click to expand...

thanks!

in the end, after studying everything I could find (mainly pics of other's crossovers) and asking around, I ended up ADDING IN a resistor R1 with a value of 15ohms

I did this because even though it seems that first-gen units probably did not have it, it seems that the later ones did (as did the TF1000s), and I assumed they must have done it to improve the sound and thus so should I

also I figured that since all the drivers plus the cabinet appear to be the exact same, the crossover was not different for any particular reason, other than simply being first-gen

btw, here's my completed TF700 restoration:

http://www.audiokarma.org/forums/showthread.php?t=678556&highlight=tf700+restoration

cheers!

Nice finding this, I have version two crossover in my TF700 I just got. First pair and enjoying the rebuild.

Happy listening!