SpeakerTalk

[GTIanz]

Scored a pair of KEF 105/3's for a good price. I've always wanted a pair as I love the very original and unique design characteristics of KEF speakers.

They are in great shape but had the expected woofer foam issues.

I have an account and thread over at audiokarma.org that I decided to bring here for additional help and future reference.

I am experiencing a problem with one of the uni-q drivers and hoping someone here has some suggestions. The tweeter is fine.... the problem is distortion/resonance at what seems like the low frequency reproduction of the midrange driver.

I have removed the driver (twice). I'm not noticing a rub in the voice coil. And it doesn't sound like the typical buzzing associated with a voice coil. It also doesn't sound like a blown driver as it only seems to impact certain frequencies and some songs sound fine.

Anyone have any suggestions? At this point I'm going to pull the driver again and take it into a local repairman.

I was considering the possibility that this isn't an issue with the driver at all but, potentially crossover components that may have fallen out of spec and are allowing too broad of a frequency range to the midrange?
_________________
Parasound Halo P5 / A21 - Infinity RSII / Kef 105/3 - Media PC
Bedroom: Onkyo TX-8500 mkII - Infinity RS4000
Dahlquist DQ10's (upgrading)

[GTIanz]

Documentation of my rebuild:

Got them moved into the house and hooked up for a short audition. Very interesting comparing them to my Infinity RSII's.

Simple and quick comparison; with no placement adjustments. Will take a lot more time and work to make a thorough comparison.

The Kef's were much more accurate and crisp in the midrange. The bass is tighter although the infinity's had quite a bit more bass output. For me the tweets were a tossup. My brother said the Infinity's tweeter sounds harsh....surprised me as I've never felt that to be the case. I didn't turn the Kef's up much to see how they sounded at higher volumes given the woofer surrounds.

My initial impression is that both of these speakers are going to excel in different areas with different types of music. Probably going to come down to a matter of taste and music preference.

As promised photo's:










Overall they are in excellent condition given their age! Wiped them down with a damp cloth. There are a few small dings and scratches. But, there are no dents or gouges. They should be very easy to clean and touch up. The plastic grill frames are 100% intact but the cloth needs to be replaced as it has pulled loose in a couple of places (I'll see if I can't clean it up and re-attach in the loose places first). And, of course I need to replace the woofer foams.
_________________
Parasound Halo P5 / A21 - Infinity RSII / Kef 105/3 - Media PC
Bedroom: Onkyo TX-8500 mkII - Infinity RS4000
Dahlquist DQ10's (upgrading)

[GTIanz]

These awesome instructions were sent to me by canuck and definitely helped in the disassembly of these speakers.

Author Jay:

Needed tools:

stereo/music

work bench

lots of light(s)

2 pieces of 2x4 (or equiv), each covered with a towel/rag

baggies

felt pen

digital camera

deep sockets (1/4 drive). Do not use a cheesy set. Sockets/extensions falling off can hurt speakers.

hex drive

phillips screwdriver

small needle nosed pliers

soldering iron/solder

Practice the mantra: Do everything slow. Do not poke speakers. Repeat throughout entire process.

Start:

1. Remove speaker grill, store in safe out of the way place

2. Put two 2x4s on table, cover with cloth, lay 105/5 face up on the 2x4s (2x4s are to keep speaker posts

on back of speaker from hitting).

Remove mid/tweeter assembly (pod)

3. Remove 4 fasteners (hex drive) attaching mid/tweeter assembly. Note at each fastener location is a

bolt, spacer, and washer (washer may be stuck to pod assembly). Bag and mark.

4. Carefully lift the mid/tweeter assy straight up just a little (approx 1.5 inch), rotate assembly slightly, gently

set down. The idea is to locate the electrical connector.

5. Grab white connector at each end with thumb and forefinger, rock back and forth and pull downward

gently, and remove connector. Note: My first time removing this connector I battled it (I did not rock it) and

broke off some of the pod connector black plastic tangs.

6. Remove pod. Note this changes the CG of the speaker * if your speaker is hanging over the table make

sure it doesn't tip. Store pod in safe place. Note also metal washers on back of pod (at each fastener hole

* they may or may not be loose).

7. Take pictures, especially noting upper woofer and wire (color) connections. Note wire run path.

Start woofer access

8. Remove white stuffing above top woofer. Note that stuffing is not pushed against speaker cone, but

rather is located above the foam ring attached to the cabinet inside.

9. Locate the bottom panel of the speaker. Remove the 8 phillips screws.

10. Gently pull bottom panel out. This panel has a crossover and wires attached to it. Take a picture,

make a sketch of the wire (color) connections. Remove all 8 spade connections. I have bent thing like this

in the past. I remove very genty, rocking back and forth, while supporting the corssover board

at the spade location.

11. Store bottom panel in safe place. Interesting to note that KEF makes (or has made for them) their own

capacitors.

12. Remove white stuffing. Take pictures. Note wire runs.

Remove "woofer rod"

13. Recon. Locate bottom woofer, note bolt head protruding out the bottom. A similar bolt is installed in

the upper woofer, only on the top woofer the bolt head is inside the the middle top of speaker.

14. Warning warning warning: speaker damage potential. Go slow. Note also that speaker magnet likes

to attach to metal tools. At upper woofer, use 10 mm socket (with extension) and attach socket to bolt head

inside speaker center. Carefully loosen and remove bolt.

15. At lower woofer bottom, use socket to remove bolt. While doing this support rod in other hand. Do not

let rod poke speaker. Carefully remove rod. Bag/mark parts.

Upper woofer removal

16. Recon: Upper woofer held in place with 3 studs on upper surface. Note bottom of woofer (remember,

photos), especially location of terminals. When reinstalling woofer note to ensure terminals are in same

location. Also note (at least on mine) that wire runs are tight. Accordingly, rather than clip wires I chose to

desolder.

17. Clip or desolder wires at speaker teminals. Warning warning: if desoldering, careful of solder falling

onto speaker. Also note that speaker magnet likes to attrack soldering iron. To desolder I used strategic

light, needle nosed pliers (to pull on the wire), and careful placement of the solder gun. Slow. Careful.

Think. Do not hurt speaker. I considered as an option leaving wires intact. However they are glued in

place on their path to the bottom crossover area and I determined it would be very difficult to free them.

18. At upper surface use deep 7mm socket (with extension) to remove nut, lock washer, nut, and washer

at each of the three stud locations. Careful, slow, do not hurt speaker. Note the torque of the nuts as you

remove them (they are not installed too tight * this is noted since later you will reinstall these and they ride

against rubber * it is a bit difficult to gauge how much torque to use). Or, perhap more intelligently, eyball

how the speaker rubber grommets are compressed (before you loosen anything) * when you reinstall these

you will want the rubber grommets compressed about the same. Bag/mark parts.

19. Remove speaker by carefully (one hand on back of speaker, other on front) pushing down. Do not

harm speaker. Slow. Careful of the studs. The foam attached to the side of the cabinets gets in the way a

bit, but foam removal is not required. Work it slow. Carefully pull speaker up and out. As I am a bit anal I

marked mine (using felt pen) with speaker serial number and "upper". Put speaker in safe place.

Lower woofer removal:

20. Note woofer crossover mounted below lower woofer on back panel of cabinet. Take pictures. Note

wire color connector locations (make diagram/sketch).

21. Gently remove lower woofer speaker connections (spades) from crossover (on mine these were red

and black wires).

22. Use socket to remove nut, lock washer, nut and washer at each of the three locations. Slow, careful. If

confused by my "rubber compression" comment in item 19 above * you are now smarter (having removed

on woofer already) and can look at these better prior to removal to gauge rubber. Bag/mark parts.

23. Speaker is removed carefullly upwards. Note cabinet particle baord crossmenber. Also note cabinet

cutout for speaker. I had to (careful careful careful * do not poke speaker * watch fingers) face speaker up

(cone up) * slide up and over particle board crossmember, then rotate and remove through cabinet cutout.

Slow slow slow.

Reassembly:

1. Reverse order above. Note: Start with lower woofer. If you install upper woofer first you cannot fit lower

woofer into cabinet.............Also, good time to look at earlier photos to acquant yourself with positioning of

things.

2. Lower woofer. Slow baby steps. Slide down into cabinet, rotate cone upwards, slide woofer past

particlae board crossmember * be careful both of wires/terminals of woofer and also existing wires in

cabinet(upper woofer wires). Feed speaker wires through bottom, as you get close to studs you can use

one hand through bottom, one through cabinet front. Also, as you slide speaker onto the mounting studs be

gentle and ensure the speaker rubber grommet does not come off.

3. Remember, flat washer against speaker, then nut, lock washer and second nut. Tighten to compress

rubber grommet (as seen during disassembly). Or SWAG it, just don't kill the rubber.........

4. Upper woofer.

5. Solder

x. Bottom cavity * Before you reinstall this ensure you have attached metal rod between woofers. install

white stuffing, reconnect wires, reattach bottom panel.

Related stuff:

B200 woofer center dust cap repair

1. Order replacement dust caps, white glue (paper cone), and black glue (plastic) from Midwest Speaker

Repair.

2. Remove old dust cap. I used a rounded blade exacto knife and methodically worked my way around

and around the speaker cutting litttle bits at a time. I found that pulling up from the cone was bad (cone

paper wanted to pull up) * I worked the blade sideways. Get some stuff on the blade, wipe it off, get stuff on

the blade, wipe it off, etc. I declared it done when I had worked the paper cone surface down flat. Residual

glue and some debris was left, but not bad. I scraped the center plastic ring surface clean with a flat

screwdriver, and then a flat exacto blade.

3. Glue on new dust cap. Using small bottle white glue came in, I laid down a small bead along the cone

along the line of the previous glue. I also coated the outside edge of the new dust cap. Using the small

bottle the black glue came in, I put a slight bead on the speaker plastic center ring, and then a slight bead

along the inside edge of the new dust cap. I carefully positioned the cap over the speaker and set it down

gently. I then moved it to align in the center and pushed down to set the "black glue" portion. To get the

outer ring of the dust cap to attach to the cone I had to gently lift the cone up. I patted the edges with q*tips

(swab end or bent in half using the stick). I had to monitor/tweak the speakers for a bit until the glue set up.

Of course the more I did the better I got.............
_________________
Parasound Halo P5 / A21 - Infinity RSII / Kef 105/3 - Media PC
Bedroom: Onkyo TX-8500 mkII - Infinity RS4000
Dahlquist DQ10's (upgrading)

[GTIanz]

And the fun has begun on my pair:









My sad post op helper:







The foam is completely shot on all drivers. A light tap anywhere and it breaks.





I'm sure there are more difficult projects out there. But, this one is intensive. Soldered speaker leads have to be done inside the cabinets. Removing the lower woofer was close to impossible with all the dampening material in the port chamber (All foam is glued in). All said I think it took me about 2 hours to get the first speaker disassembled. Sure the second one will go more quickly. time to order the foams and see if I should be attempting projects like this. Wish me luck!
_________________
Parasound Halo P5 / A21 - Infinity RSII / Kef 105/3 - Media PC
Bedroom: Onkyo TX-8500 mkII - Infinity RS4000
Dahlquist DQ10's (upgrading)

[GTIanz]

Embarrassing, but I left this part as is:

Ok I have ventured into territory that is making me very uncomfortable. I want to try to replace the likely dried up ferro fluid.

But, these things are assembled like tanks. Some seriously tight tolerances and glue everywhere. Don't think these things were built to be serviced. On one of the cabinets I can't even get the aluminum cap off.

Does anyone know how to get the Uni-Q driver out of the damn cabinet?






Edit: figured it out. The uniq and likely the midranges aren't even screwed in. They are coupled to the cabinet via the aluminum caps on the rear. The drivers themselves can be pushed out the front of the pod quite easily.
_________________
Parasound Halo P5 / A21 - Infinity RSII / Kef 105/3 - Media PC
Bedroom: Onkyo TX-8500 mkII - Infinity RS4000
Dahlquist DQ10's (upgrading)

[GTIanz]

This part of my build I still have questions about. Has anyone attempted replacing the ferro-fluid on 105/3 uni-q tweeters? Do these tweeters have the same problems of drying out like the 104/2?

[GTIanz]

I ordered the refoam kit from Springfield Speakers off of ebay. Nice packaging.



Spent a couple hours cleaning up the woofers last night and I still have a couple more hours of to go. Hopefully I can get the outer surrounds done today/tomorrow.





Glue residue removal. The glue on these woofers is still sticky and refuses all attempts I make to take it off.

I got the edges easily simply using my fingers and a little water to clean my fingers. Easy on the edges but, it doesn't work very well when the glue can stick to the cone at the centers.

I have tried pure isopropyl alcohol, crud cutter , and windex. None are breaking down the glue. I'm going to try to remove a little bit more but more than likely I'll just use the old glue as a guide for the new donuts.



edit: Taking extra time and being patient I was able to remove most of the glue with pure isopropyl alcohol. Using a q-tip I'd apply the alcohol to the glue - let it sit for 30 seconds or so and then slowly use my thumbnail to push/roll the malleable glue until it accumulated enough to pinch off. Rinse and repeat. Think it is impossible to remove all the glue and I'm not sure one would want to. The alcohol on a paper towel is also very effective at cleaning glue residue off the basket.
_________________
Parasound Halo P5 / A21 - Infinity RSII / Kef 105/3 - Media PC
Bedroom: Onkyo TX-8500 mkII - Infinity RS4000
Dahlquist DQ10's (upgrading)

[GTIanz]

found the crossover schematic for the 105.3's at:

[URL="http://www.hifiloudspeakers.info/speakertalk/viewtopic.php?t=250"]www.hifiloudspeakers.info/[/URL]


_________________
Parasound Halo P5 / A21 - Infinity RSII / Kef 105/3 - Media PC
Bedroom: Onkyo TX-8500 mkII - Infinity RS4000
Dahlquist DQ10's (upgrading)

[GTIanz]

Finished everything up and got the speakers put back together without too much trouble.

The good news:
All woofer re-foams went smoothly. No rubbing on any drivers. Probably not the prettiest job but not bad for my first re-foam IMHO.


I had read somewhere else that 3 guides worked well for them. The voice coil gap is tight....I couldn't get a 4th piece in. Inserting the guides was also a bit of a challenge as the center post blocks direct access to the voice coil gap.

I used a very small flat head screwdriver to nudge the bottom of the guide into the gap.

When gluing in the donuts large sockets are very helpful to hold down the center of the donut.

I'm also making progress on the grills. The glue supplied with the refoam kit is working very well.


Earlier I complained about how difficult it was to de-solder the woofer leads inside the cabinet. If I were paying attention at all I would have noticed that the lower woofers can easily be removed without de-soldering!



After noticing this I pulled the leads and re-attached outside of the cabinets. Made the re-install much easier.
_________________
Parasound Halo P5 / A21 - Infinity RSII / Kef 105/3 - Media PC
Bedroom: Onkyo TX-8500 mkII - Infinity RS4000
Dahlquist DQ10's (upgrading)

[exkefman]

Hi,

That's a long post.

Glad you've made progress on the re-foam side.

For the "questionable" Uni-Q driver, to eliminate the drive unit, I would just swap the entire front "assembly" (1x Uni-Q + 2x Lower MF units) as it uses a plug in connector.

If the "issue" switches to the other main cabinet, it's within that front assembly. if it "stays" with the original main cabinet, it could be something that is loose and resonating at a specific frequency.

I very much doubt the x-over is at fault, as the solder joints are usually pretty much "bomb-proof". Likewise the inductors are held with ty-raps, so you could check those are still "firm".

EDIT: If you found some coil rub, then be careful - it might just be some grit or dust that is caught up...with the tweeter disconnected, you could try running some very low level (enough to make the cone move a little) music signal into the upper-midrange drive unit for say 10 minutes, keeping the drive unit face up and resting on it's magnet - so the drive unit will be moving slightly and if there is debris in the gap, it might just fall down into the magnet gap.
_________________
regards
Tim

(I used to work for KEF from 1988-1995 - you can see my "profile" here: http://www.hifiloudspeakers.info/speakertalk/viewtopic.php?t=1706)

[GTIanz]

[exkefman]

[speakerguru]

[exkefman]

Hi SG,

It's the "upper" MF unit on the 105/3 that has the issue...so it doesn't have a dust cap....!!
_________________
regards
Tim

(I used to work for KEF from 1988-1995 - you can see my "profile" here: http://www.hifiloudspeakers.info/speakertalk/viewtopic.php?t=1706)

[GTIanz]