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This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
I rescued a pair of Beovox P45 loudspeakers from a thrift store that supports the local schools on Florida's east coast. Here's a side view of both of them. The white material appears to be paint.
Yes, these were neglected and/or abused at some point in their existence.
The veneer glue is failing in at least one corner.
I pried off the frets (grills) using a drywall putty knife. The frets were glued in place and not clipped like the M70s, S45-2s, S40s and P30s I own.
The tweeters appear to be the same as M70 and P30 tweeter.
The midranges (or are they phase links?) do not appear familiar to me.
The woofers do not appear familiar to me either.
They look like Soren's though.
Alas - none of the woofers work. No sound comes from any of them. Three have seized cones. The one whose cone moves freely moves TOO freely. It may have a broken lead.
So - what to do with them?
Lassi's S45-2 woofer repair thread for future reference.
Think I'm going to need it.
My frets was glued too, the wood frame corner has come unglued, just a matter of gluing and press it together again, the frame construction is flimsy.
I would like to get a shot on repairing the woofers, or, depending on the price buy them, I dont need them, but as always I want to save them if possible.
PM me with your price and shipping cost, if you dont want to keep them, if you want to keep them, let me repair the woofers, only shipping and material cost.
Collecting Vintage B&O is not a hobby, its a lifestyle.
Let me open them up before deciding what I'm going to do with them. I may want to have a go at those woofers, too!
Rich: Let me open them up before deciding what I'm going to do with them. I may want to have a go at those woofers, too!
Ha Ha, the virus at work, and as you always say, without pics, it did not happen. My P45s (new caps) was playing a little (some 10 hours) with my BM 2400, I then shifted to the BM 4400, After some 20 hours the sound got better, I dont know if it was the P45s or the BM 4400, or maybe both, but very good sounding speakers. And wall hanged, save space. Go for it Rich.
The project queue is down to zero, so it was time to get these thrift store P45s out again. I've disassembled the speakers completely and reread Lassi's thread on S45-2 and P45 woofer repair. Thanks to Lassi's tip, I tried to just pull the stuck woofers apart with my hands. Success!
The fourth woofer was not stuck, but common sense says it will eventually get stuck so I tried to pull it apart as well. No luck.
But then I gently tapped the side of the magnet with a hammer. Seriously - just one gentle tap. Then I tried to pull it apart and success! Just the slightest jarring during handling and that fourth woofer was probably going to get stuck.
I checked electrical continuity of each woofer. I had continuity on 2 of the 4, with these 2 each having DC resistance of 7.4 ohms.
I desoldered the leads of one of the others and then had continuity.
Unfortunately, the fourth woofer has a broken lead.
The good news is, there is still continuity of the voice coil. Just have to fix the lead, I guess. That'll be a new one for me.
Following, interesting, good luck
Hey, Soren. I thought you were heading to Texas? Or is that next weekend?
By carefully getting under the dust cap with an X-acto (hobby) knife, I was able to remove the dust cap of the woofer with the broken lead without cutting the dust cap. Should make replacing the dust caps easier if they are removed entirely rather than cut just above the original glued area.
Also with the X-acto (hobby) knife, I was able to pry up the broken lead from the cone.
I tinned the ends of the braided lead with solder, then repaired the break by resoldering.
Then it's just a matter of threading back through the existing hole in the cone and pressing down into the cone.
I then applied some "The Wet Look" to the repaired area as an adhesive. I used clear because that's what I had on hand, but black (which is available) would have better matched the existing driver. I'm not too concerned, though, because the fret cloth will obviously cover the drivers in the end if this repair works.
And now it's off to the DIY store (Lowes) to get some epoxy.
Rich: Hey, Soren. I thought you were heading to Texas? Or is that next weekend? By carefully getting under the dust cap with an X-acto (hobby) knife, I was able to remove the dust cap of the woofer with the broken lead without cutting the dust cap. Should make replacing the dust caps easier if they are removed entirely rather than cut just above the original glued area. Also with the X-acto (hobby) knife, I was able to pry up the broken lead from the cone.
Going to TX tomorrow, will try the dustcap technique on my next one (CX100)
Nice project. Keep up the good work.
-sonavor
sonavor: Nice project. Keep up the good work. -sonavor
Couldnt agree more.
Ricardo: sonavor: Nice project. Keep up the good work. -sonavor Couldnt agree more.
Thanks, guys. That means a lot coming from you two; I greatly admire the work of both of you.
Yesterday I was able to completely disassemble all four woofers, keeping all the parts for each unit together. I took no photographs since I was watching the golf tournament in the living room and doing the work over an end table. The short version: (1) the rubber surround easily comes off the basket once you pry up a spot with a hobby knife; (2) spider was cut with a hobby knife; and (3) last bit of desoldering the leads was completed.
Today I started the long process of reassembly. First I cleaned the bottom of a basket and the top of a magnet assembly with Goof Off sheets and scraping with a hobby knife and a putty knife. The set on the right has been cleaned, the set on the left not.
The next step really should be done in a vise. Alas, I don't have one, so improvised. Below you will see my makeshift vise: a fairly heavy-duty spring loaded clamp and a 30 pound dumbbell.
Inside the magnet assembly you can see 4 x 4" long pieces of stiff wire (snipped from a roll of picture frame hanging wire) to serve as centering shims.
I then mixed a bit of this two part epoxy on a small plastic plate with a craft (popsicle) stick.
Then I spread the epoxy on the magnet with another craft stick. A little goes a long way. I'm sure you don't want to put a whole lot on - one needs to prevent material from squeezing into the air gap.
I did two of the woofers today, and didn't take photographs of this step either time! I'll do the other two tomorrow. I'll try to photograph this step tomorrow!
Then I carefully and slowly lowered the basket down onto the magnet assembly. Eventually the magnet pulls the basket down with a good tug. The wires do keep the basket centered so that the center pole looks pretty good.
I forgot to photograph this step, too!
I removed the assembly from the vise, bent the wires over (but left them in the air gap), inverted the assembly, placed it on a table, then put a weight on top of it. Very little material came out the outside edge, so I'm pleased with the amount of epoxy I used.
I will let the two I got epoxied set overnight before disturbing them.
Good work Rich, like the technique, gluing the basket to the magnet without spider and voice coil attached makes sense, If done with spider and voice coil attached you will never know where the magnet goes. I would like a pic from, where did you cut the spider. Orava did it with the spider attached I think and I never quit understood that. But maybe we will get the same discussion here as we had with shimming
Søren Mexico: Orava did it with the spider attached I think
Orava did it with the spider attached I think
No - for both the S45-2 and P45 he cut the spider along the outside and used what looks like PVA to glue back.
I applied the epoxy to the other two magnet/basket assemblies tonight. Here is a shot of the epoxy spread on the magnet sitting in my makeshift vise.
And here's a shot of an assembly after setting the basket down. At this stage it is still possible to tweak the position so just nudge the basket a bit if you're obviously not centered.
If I receive my glue kit from Simply Speakers tomorrow, I will start attaching cone/surround/spider assemblies to the magnet/basket assemblies. If not, I will start desoldering the crossover networks. As with the P30s I refurbed earlier this year, I will be replacing the capacitors and resistors.
Rich: No - for both the S45-2 and P45 he cut the spider along the outside and used what looks like PVA to glue back.
Yap, with PVA. I think it might be bad if sidewall of spider is flexible, so I think PVA is ok.
blah-blah and photographs as needed
Dom
2x BeoSystem 3, BeoSystem 5000, BeoSystem 6500, 2x BeoMaster 7000, 2 pair of BeoLab Penta mk2, AV 7000, Beolab 4000, BeoSound 4000, Playmaker, BeoLab 2500, S-45, S-45.2, RL-140, CX-50, C-75, 3x CX-100, 3x MCL2 link rooms, 3x Beolab 2000, M3, P2, Earset, A8 earphones, A3, 2x 4001 relay, H3, H3 ANC, H6, 2014 Audi S5 with B&O sound, and ambio
Thanks, Dom. I'm thinking a great little system some day would be these P45s matched with a Beocenter 3500 and the Beocord 8004 I just got back from the shop! No pressure though....
May I speak to the inefficiencies of the United States Postal Service (USPS)?
Here's the story. I buy an adhesives kit on the internet from Simply Speakers of St. Petersburg, Florida, about a 2 hour drive from where I live in Orlando. This was Monday, and I chose USPS Priority Mail for the shipping option. On Tuesday Simply Speakers ships the kit and provides me with a tracking number. The USPS web site says I should expect the kit the next day, on Wednesday.
Wednesday (yesterday) afternoon, no kit is in the mail. No worries, the family decides to spend the evening at Universal Studios where we are annual pass holders.
This morning (Thursday) I check the USPS web site: at 4:00 am the kit passed through the Miami, Florida sort facility! The kit was driven from St. Petersburg to the Tampa airport, then flown to Miami airport, then driven to a sort facility there! Are they going to send it back to the Miami airport and fly it up to Orlando?!?! Time will tell!
The really funny thing is, if I had just chosen first class mail for less money, the USPS probably would have driven the kit straight from St. Petersburg to Orlando and I'd already have it.
Anyway, rant is now off.
Today I bought a tube of Aleene's 7800 Adhesive from Michael's crafts store to use as the rubber surround to basket adhesive. I have one cone surround now glued to a basket as detailed below.
First I cut four thin strips from the joker of a brand new deck of cards. One end of the strip went into the air gap, and one end came out of the basket. These four strips will serve as shims for the outside of the voice coil.
Rich: May I speak to the inefficiencies of the United States Postal Service (USPS)? Here's the story. I buy an adhesives kit on the internet from Simply Speakers of St. Petersburg, Florida, about a 2 hour drive from where I live in Orlando. This was Monday, and I chose USPS Priority Mail for the shipping option. On Tuesday Simply Speakers ships the kit and provides me with a tracking number. The USPS web site says I should expect the kit the next day, on Wednesday. Wednesday (yesterday) afternoon, no kit is in the mail. No worries, the family decides to spend the evening at Universal Studios where we are annual pass holders. This morning (Thursday) I check the USPS web site: at 4:00 am the kit passed through the Miami, Florida sort facility! The kit was driven from St. Petersburg to the Tampa airport, then flown to Miami airport, then driven to a sort facility there! Are they going to send it back to the Miami airport and fly it up to Orlando?!?! Time will tell! The really funny thing is, if I had just chosen first class mail for less money, the USPS probably would have driven the kit straight from St. Petersburg to Orlando and I'd already have it.
Yeah, I have ALWAYS found that "first class" or "Priority" mail are the secret sauce in the Postal service in almost every case. With things often showing up surprisingly quickly in some cases, that I didn't even expect. I ship Beosound 9000s via Priority and find it to get the item to my customers more quickly, with less handling than either UPS or USPS and at a similar cost to boot, if not less. It's REALLY impressive when things are moving from one coast to the other. USPS absolutely blows the other two away in those cases (when not using overnight services obviously).
Nice work on the speakers.
I put a small bead of the Aleene's 7800 on both the underside of the rubber surround and the basket, per the adhesive's instructions. Also per the instructions, I waited 5 minutes before pressing the parts together.
Forgive the lack of photographs for the next steps, but once the glue reaches the 5 minute tacky mark, I think you should work fairly quickly.
So - at the 5 minute mark I put the cone partly in place in the vertical direction. In the horizontal/rotational direction, I made sure to line up the braided wires to the leads and the cut I made in the spider. (The side view below will illustrate the horizontal/rotational line up.)
With the voice coil partly inserted into the air gap, I placed 3 shims on the inside of the voice coil. These shims were clear plastic strips I had in hand from earlier refoaming projects.
After the shims were in place on the inside of the voice coil, I made sure outside shims were OK and the spider was still aligned horizontally/rotationally. With all OK, I slowly pressed the cone down until the rubber surround made contact with the basket. I then pressed down all around a couple times with a finger, then a couple times with the end of the handle of an Xacto (hobby) knife.
I then put the 8 clamps on as seen in the photograph. I must say, when I bought this kit of clamps (which includes a few bigger ones than shown), I thought I would never use the smallest clamps.
After the clamps were in place, I pushed down on the surround between the clamps one more time.
And here's a side view after rubber sound to basket attachment. Make sure the peaks and valleys of the cut to the spider match for gluing later. Of course, also make sure the braided wire from the voice coil is aligned to the leads for later soldering.
I took the clamps off the first woofer and couldn't resist testing it before repairing the spider and replacing the dust cap.
Success!
You can clearly see bare metal on the basket in this shot. The woofers all had some oxidation on them - white Aluminum oxide (Al2O3 if I remember my college chemistry). I scraped all the residue off each woofer during cleanup, and I will paint the bare metal with some black acrylic hobby paint I have on hand.