ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Søren Mexico: If grey goes to spade terminal, thats OK, I dont see any yellow wire, the brown wire in your pic is positive, to round pin terminal
If grey goes to spade terminal, thats OK, I dont see any yellow wire, the brown wire in your pic is positive, to round pin terminal
Søren,
I am confused, both terminals are the same, flat tab posts.
In the picture connecting to the black, blue, and white wires goes the grey wire. The lower tab gets the yellow wire, not shown as it is very short and is connected to the speaker housing.
Jeff
Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Beogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 4500, Beocord 5000 T4716, Beocord 5000 T4716, Beocord 5000 T4716, Beocord 8004, Beocord 9000, Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century, S-45.2, S-45.2, S-75, S-75, M-75, M-100, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase, B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder
Piaf:I am confused, both terminals are the same, flat tab posts.
Me too (confused)
You will have to check further: use your ohm meter, check continuity between Gray, black, blue and white wires ("0" Ohms)
Check that both crossovers are wired in the same manner
If this is all OK, you will have to unscrew the crossovers and check that the new caps and the wires are correctly connected according to drawing
Collecting Vintage B&O is not a hobby, its a lifestyle.
Wow!!! I just put foam sealer(just a generic weather strip type of foam) where the plastic speaker holder(face plate) meets the wooden cabinet. They sound like a different speaker! The bass is here, before it seemed a bit muddy and not tight and crisp(it even seems to sound louder). Now it is. These little guys are starting to impress me. I think they just needed some TLC. That is the update for now. More to come when they get re capped
cbn700: Wow!!! I just put foam sealer(just a generic weather strip type of foam) where the plastic speaker holder(face plate) meets the wooden cabinet. They sound like a different speaker! The bass is here, before it seemed a bit muddy and not tight and crisp(it even seems to sound louder). Now it is. These little guys are starting to impress me. I think they just needed some TLC. That is the update for now. More to come when they get re capped
Did you check that Jeff ??
There was some thin black stuff at the top of the speaker(but the rest was gone), but bought some foam weather strip stuff from a local hardware store and it seems to have done the trick.
cbn700: There was some thin black stuff at the top of the speaker(but the rest was gone), but bought some foam weather strip stuff from a local hardware store and it seems to have done the trick.
I use the same for all my speakers, also for driver to front plate if not there.
Søren Mexico: cbn700: Wow!!! I just put foam sealer(just a generic weather strip type of foam) where the plastic speaker holder(face plate) meets the wooden cabinet. They sound like a different speaker! The bass is here, before it seemed a bit muddy and not tight and crisp(it even seems to sound louder). Now it is. These little guys are starting to impress me. I think they just needed some TLC. That is the update for now. More to come when they get re capped Did you check that Jeff ??
No, but I will!
Mine don't have any sealing problems. Bass is reasonable but very dry that's all. On organ music I can most definitely hear some of the lower notes.
On The Day Before You Came (ABBA) the very obvious bass is all here.
Elevator speakers Jeff? Nah!
Jacques
chartz:Elevator speakers Jeff? Nah!
Jacques is here too now, and Jeff remember, we never give up on a piece.
Give up? Me? Never!
After re-foaming and re-capping I hoped for a transformation that was elusive. This frustrating sage went on longer than Søren’s Beomaster 4400 adventure, and a whole lot less rewarding.
I found the strip of insulation on the top, just as described and had modest hope that placing insulation all around would accomplish all that was promised.
So did it? Well yes to the extent that the volume really increased as did the bass, both being goals of all my efforts to date. So I consider this a reasonable success.
Jacques appears to appreciate his MC 102.2’s and I am happy for him, I really am.
The lifeless, flat elevator music has been banished and I thank one and all for this. However if asked do I find my MC 120.2 speakers to be wonderful? The honest answer is no, kind of like the guy who compared his S 30’s with his S 45.2’s and didn’t like the comparison.
In every respect I find the “new” MC 120.2 sound inferior to my tattered, purchased CHEAP one at a time on eBay S 75 speakers. (gifted to me by a friend)
This friend believes, as do I that there is a design flaw in the crossover network that causes confusion as to what sound is delivered to the tweeter or the mid-range.
Perhaps Jacques has a brawnier amp than mine to power his MC 120.2 speakers. I have a badly compromised amplifier that I have I kept alive by respecting its limitations. In this case I pressed it much harder than I was comfortable with and still the MC 120.2’s disappointed.
One pleasant surprise from my “blasting” these MC 120.2 speakers to the point the overload lamp flickering, the amp never got beyond warm. (I always monitor the temperature.)
As a result with the MC 120.2 speakers performing the way they do now in combination with the S 75 speakers….. AND my amplifier being able to handle it without heavy breathing, I am a happy camper.
Thank you BeoWorld!
I´m glad we, thanks to CBN700, found the failure, I have always been careful with gaskets, replaced or repaired, even closed wire holes with silicone in the older speakers, and thought this was common knowledge. I´m sorry that the MC 120.2s are not up to your expectations, but at least they now sound better than before. The idea of bad or wrong configured crossovers may be something to think about, for members with more knowledge of speaker building, than we normal grassroots.
Good job and I love persistence
Glad that helped out. That is what we are all here for to share knowledge, and help each other out
cbn700: Glad that helped out. That is what we are all here for to share knowledge, and help each other out
So true and very much appreciated! I really DO thank you sincerely!
You just replaced the bit of foam strip at the top like below that's it? Or did you correct a possible design flaw and do the other sides too?
http://archivedarchivedforum2.beoworld.org/cfs-filesystemfile.ashx/__key/CommunityServer.Components.PostAttachments/00.00.22.26.29/DSC02459.jpg
How can that improve anything at all I would like to understand!
Praise indeed coming from you.
Søren, we are all here trying, fighting to keep a dream alive.
This was a win for the team.
chartz: You just replaced the bit of foam strip at the top like below that's it? http://archivedarchivedforum2.beoworld.org/cfs-filesystemfile.ashx/__key/CommunityServer.Components.PostAttachments/00.00.22.26.29/DSC02459.jpg How can that improve anything at all?
You just replaced the bit of foam strip at the top like below that's it?
How can that improve anything at all?
Jacques,
I can not begin to explain how this worked, but I assure you, my misgivings notwithstanding, it did.
Of course I added to the top strip by "completing" it all around and that made ALL the difference.
Still crappy speakers, but much, much improved.
Do you ever sleep Jeff?
There was some old foam sealing strip at the top and that was it. I put a new seal all around the cabinet and then re installed the plastic cover that holds the speakers. The cabinet seems to be a ported type box so without a good seal it was not working properly?? If that makes any sense
I checked out the link and mine were like that only less foam remaining and what I had was maybe half as wide.
We are dealing with a pressure chamber (cabinet) the woofer moves a lot of air, forward and backward, if the cabinet is not perfectly sealed this effect will be lost, the bass reflex tube will not function. this effect is specially seen in RL 60, where older models has a bass reflex plate, later models has a tube, but the whole cabinet is constructed to use this effect.
I've just finished the mod. I don't understand: there is now much less low bass, and the overall sound is degraded and coloured. Where is that lovely bass in The Day Before You Came? And that double-bass on the Brad Mehldau CD? And those organ pipes? All gone and reduced in size!
Upper bass does seem to be strengthened but this doesn't sound too good.
Sorry guys, this doesn't do it for me at all. No, no, no.
I'm sure B&O engineers had a good reason for partially sealing the cabinet, and I think I've found it.
I use a Beomaster 8000 sans filters engaged.
chartz: Do you ever sleep Jeff?
Hi Jacques,
Sleep? Why of course.
You are 9 hours ahead of me, which makes communicating a bit of a challenge. I replied at 11:00PM just before going to bed, whereas it was 8:00AM your time, and I assume you were getting up.
I know this off the top of my head as my better half just got back from the UK on business and London is 8 hours ahead. (The rest of Europe 9 hours, which no doubt you already know….)
chartz: I've just finished the mod. I don't understand: there is now much less low bass, and the overall sound is degraded and coloured. Where is that lovely bass in The Day Before You Came? And that double-bass on the Brad Mehldau CD? And those organ pipes? All gone and reduced in size! Upper bass does seem to be strengthened but this doesn't sound too good. Sorry guys, this doesn't do it for me at all. No, no, no. I'm sure B&O engineers had a good reason for partially sealing the cabinet, and I think I've found it. I use a Beomaster 8000 sans filters engaged.
I am no engineer and surely I don’t know why the modification would have such a negative effect on your speakers; however you ARE using a Beomaster 8000 which has the power apparently REQUIRED by these power hungry beasts.
Everything I did, re-foaming, re-capping, checking polarity, and by-passing the defective overload circuit made only the slightest changes in the overall sound.
Sealing the cabinet increased the volume about 50% (and that is a LOT) and at the same time increased the bass about 150%.
So we are talking a major improvement, to the point that these MC 120.2 speakers are now acceptable in my eyes (ears). That said they are inferior in every aspect to the S 75’s that share the Beomaster 4400.
The S 75’s are much more believable if one closes their eyes, the highs are crisper and there is much more bass. Sealing the cabinet merely closed the gap…… but I gotta tell you, previously the MC 120.2’s were terrible, just awful, unforgivable. Now they sound reasonable and I am guessing if I had a BM 8000 to power them, I might have a different opinion of them.
You know they sound the same with the Beomaster 6000, which gives about 40W - the 8000 will give about 75W so it is no powerhorse either!
The MC120-2 is an 8 ohm loudspeaker, as I believe the S series were 4 ohms.
chartz: You know they sound the same with the Beomaster 6000, which gives about 40W - the 8000 will give about 75W so it is no powerhorse either! The MC120-2 is an 8 ohm loudspeaker, as I believe the S series were 4 ohms.
I thought the Beomaster 8000 was rated at 150 watts per channel making it the most powerful Beomaster ever. Is this not so?
And oh my goodness, ohms ‘vs. watts that goes back to high school, for me in the early 1800’s. I have a vague sort of memory that there is a direct relationship between watts and ohms, but please don’t ask me what that might be.
In addition my McIntosh behemoth has speaker choices for 2 ohms, 4 ohms, and 8 ohms. I also sort of remember when I was running 18 speakers off the McIntosh that “for safety sake” they chose the 4 ohm setting rather than the 8….. for reasons, explained at the time but that absolutely elude me now.
I think this calls for a second cup of coffee.
In any case the 4 ohms ‘vs. the 8 ohms would definitely give the S-Series a volume advantage over the MC 120.2’s.
In the view of this enthusiast as opposed to a qualified engineer I suspect the MC 120.2 speakers were aimed at the European market rather than the North American, as the 8” woofer allows for a sleeker cabinet at the expense of bass reproduction.
I mean let’s be frank the MC 120.2 speaker is a gorgeous svelte speaker whereas the S 75 is a bit bulky in appearance. However the S-Series delivers considerably better than the newer, lighter, and more stunning MC 102.2.
I also accept the view of my buddy and fellow B&O collector in California who feels there is a real design flaw in the crossover network (I mentioned this before) and this causes the upper end to be both confused and muddy. Mine are in any case. Throw in modest bass and the package just doesn’t impress, at least by North American expectations.
B&O proudly announced 150+150W for their Beomaster 8000 but I think that was intended for the big MS150 which I believe was more a 4 ohm speaker than the quoted 8 ohms. This remains to be verified though. But since it had the same unit as the MC120 and yet another bass unit...
Anyway, the quoted power has to be about halved hence the 75W figure. A transformer-equipped amplifier, typically a valve one or a Mac has tapped windings so impedance can be adapted to the speaker's real impedance.
In an ideal world, this should work. But then my valve amp sounds better on its 16 ohms tap, with a 6 ohms speaker, notwithstanding the poor theoretical match. Go figure.
I insist that your mod has indeed reduced bass output. Same result whatever amp I use. I realized that after modding the left speaker but I wasn't sure - my room is not symetrical.
Ohm's law goes V=IR by the way. But of course a speaker is not only resistive...
Did you know that M. Louis Ampère was French (from near Lyon)? Volta was Italian, Watt Scottish...
chartz:I insist that your mod has indeed reduced bass output. Same result whatever amp I use. I realized that after modding the left speaker but I wasn't sure - my room is not symetrical
If I read you correctly you are “insisting” that the sealing of the cabinet to the plastic speaker housing has reduced my bass. This is definitely and absolutely incorrect.
Both the volume and the bass have dramatically been INCREASED not reduced. The only way you could possibly have reduced the bass these MC 120.2 made was to turn the amp OFF! You would have needed to put money in them just to register pathetic.
Whereas I am not thrilled with these speakers, I am most definitely THRILLED with the change sealing the cabinet made. I understand that you experienced a different result, which I can not account for, but the change here took my speakers from unacceptable to acceptable.
At my place, the mod has most definitely reduced bass level, and it's very obvious believe me!
Where are your speakers placed? Mine are about 40 cm from the back wall.
I'm about to take the sealing foam off.
What is going on here, that makes us draw opposite conclusions? Oh dear!
The Beomaster 8000 produces 150W into 4 ohms. It will produce 100W into 8 ohms. Will work fine with the S120.
Peter
Piaf:Both the volume and the bass have dramatically been INCREASED not reduced.
I wonder if your speakers just weren't properly put together before your weatherstripping operation... internal damping material blocking the bass ports or something?
--mika
Am I following this thread correctly? We're converting a bass reflex design to a sealed cabinet? Are you also changing the effective volume of the cabinet (decreasing)?
Every woofer spec I've ever seen with recommended box sizes for both vented and sealed designs always has a much smaller box for the sealed design.
richhaffner:Am I following this thread correctly? We're converting a bass reflex design to a sealed cabinet? Are you also changing the effective volume of the cabinet (decreasing)? Every woofer spec I've ever seen with recommended box sizes for both vented and sealed designs always has a much smaller box for the sealed design. More blah-blah, 0-1 photographs per post
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
Of course we don't plug the port!
As I said before, I think that partially sealing the speaker does serve a purpose.
What I did actually ruins the speakers' balance for me.
chartz: At my place, the mod has most definitely reduced bass level, and it's very obvious believe me! Where are your speakers placed? Mine are about 40 cm from the back wall. I'm about to take the sealing foam off. What is going on here, that makes us draw opposite conclusions? Oh dear!
Previously I had the MC 120.2 speakers elevated about 1 meter, but with all the problems I was having with them, including one going completely dead, I swapped them with the S 75’s.
I really was much happier esthetically speaking with the beautiful MC 120.2 speakers highly visible, if audibly annoying and the S 75’s under a black stand for my Beogram 8000 and Beomaster 4400, the S 75’s flanking an unused single S 45.2 I use as a stand for my 8-Track. (Yea I know, ouch, an 8-Track.)
Currently I have the MC 120.2’s on the hardwood floor under the black stand. They sound so much better now and I believe that the bass is enhanced by being on the floor.
In any case I don’t think I like the improved sound enough to swap them again with the S 75’s. Although I might.
Peter: The Beomaster 8000 produces 150W into 4 ohms. It will produce 100W into 8 ohms. Will work fine with the S120.
Peter,
Ah ha, I thought so. And I am willing to bet that the extra muscle of the Beomaster 8000 makes a difference in the overall performance of the MC 120.2 speakers, certainly under high demand.
tournedos: Piaf:Both the volume and the bass have dramatically been INCREASED not reduced. I wonder if your speakers just weren't properly put together before your weatherstripping operation... internal damping material blocking the bass ports or something?
Mika,
I am not sure how to respond to this. Not put together properly? The woofers were professionally re-foamed and certainly look terrific and the rest of the interior looks to have been untouched, until I came along.
DMacri: richhaffner: Am I following this thread correctly? We're converting a bass reflex design to a sealed cabinet? Are you also changing the effective volume of the cabinet (decreasing)? Every woofer spec I've ever seen with recommended box sizes for both vented and sealed designs always has a much smaller box for the sealed design. More blah-blah, 0-1 photographs per post No, Rich they are just sealing the extra leaks in the cabinet. I don't think anyone plugged the port.
richhaffner: Am I following this thread correctly? We're converting a bass reflex design to a sealed cabinet? Are you also changing the effective volume of the cabinet (decreasing)? Every woofer spec I've ever seen with recommended box sizes for both vented and sealed designs always has a much smaller box for the sealed design. More blah-blah, 0-1 photographs per post
This is correct, no attempt was made to plug the port. Having said that, what port and why would I want to plug it?
All I did was follow the suggestion to complete the seal between the box and the plastic speaker surround. The author said it gave him entirely new speakers and it certainly enhanced mine!
chartz: Of course we don't plug the port! As I said before, I think that partially sealing the speaker does serve a purpose. What I did actually ruins the speakers' balance for me.
While this simple procedure ruined Jacque’s speaker balance it gave mine, as stated a bit back in this thread about 50% more volume, which I am grateful for, and about 150% more bass. That said 150% of next to nothing is not entirely something to brag about, but I’ll take it, that much is for sure!
Also as stated previously I believe that if I had a need for a third pair of speakers in my living room, which I don’t, that the McIntosh 2255 and its 500 watts of continuous power would be better suited for these MC 120.2 speakers.
However as it is I already have to sets of extremely inefficient speakers in usage with the McIntosh, Linn Isobaric’s and McIntosh ML-2’s.
My speakers are used differently: they are on their original stands and with plenty of air around them. They are 2 metres apart, very far from the equipment. My room is about 30 square metres.
Anyway, they are not floorstanders in any way!
In my present house none of my speaker placements are ideal, not even close.
Pity my poor McIntosh ML-2’s, 42 years old, really deserving of a little bit of respect and they are playing directly into the back of a 10’ suede sofa. (That is a little over 3 meters, with .5 meter in-between the sofa and the speakers.) It couldn’t possibly be worse than this, yet all considered, it works for me. You will just have to trust me on this!
The speakers in the dining room fare a bit better, although any audio expert would have an instant migraine the minute they saw the set up. The MC 120.2’s are fairly close at hand and on the floor…. Aspirin anyone?
But even worse the S 75’s are sitting side by side, no more than 1’ apart; surely it couldn’t get much worse than this.
However it is a small room, designed as an occasional bedroom and used as a dining room, for a 2,800 square foot house that doesn’t have a dining room. (The architect should really be taken out and shot!)
Admittedly my stereo set-ups are far from what they should be, but with this crazy house, each set-up was well thought out to be the best it could be, and nothing, but nothing explains why my MC 120.2’s were so God-awful before this sealing exercise.
It sounds to me like your speakers were placed by an acoustical engineer. Mine look like I hired Groucho Marx.