Eric, did you push in the Xovers in the right sense? Solder track side to the outside, component side of the crossovers towards the speakers? It happened to me…
I think this may be a case of learning to walk before learning to run, Dave!
There's certainly no point in replacing the crossovers with second hand ones which have identical componentry.
Falcon Audio provide an enhanced crossover board at a not insubstantial £182 a pair!
B139B B110A T27A network, KEF Concerto, Falcon Acoustics 33Mc Recommended MF & HF Super Power Upgrade.
I think replacing the electrolytic capacitors on his existing boards would be the most cost effective and approachable upgrade option for Eric.
The black layer on silver plated contacts in connectors, switches etc
acts as a good insulator.
It may be called Silver sulfide, but I will not swear on it.
Didn't you ever wipe it off with a glass brush or took it away with a
suitable contact cleaner (sic!) ?
Back to topic - it may be the same here ..
Hello everyone… I think this topic kan be closed now…😱😱😱
I feel so ashamed that I have bothered you 😱😱😱... for nothing really .
On Jean-Paul's advice, I wanted to measure the continuity of the connector.
So I remove the frontpanel , and what do I see ???
Someone had put the CO's in reverse.. How stupid can one be...
Yes, it's stupid stupid stupid, hard and embarrassing to admit this, but I want to be honest about it.
I also have an explanation for this. We have a cat (Main Koon). But our cat is still playful and loves to use her nails...
So I put the front panels back on as soon as possible, to prevent the cat from damaging the speakers.
But I don't want to blame the cat now either. It's just my own fault. And I'm sorry for all the thinking I've put you through.
But I've learned a lot in the meantime. For example, I also read that it is advisable to renew the capacitors of the CO
These can be purchased from Falcon. A set of 2x5 capacitors.
This could especially make a difference for the mids and highs.
So: again my apologies and thank you all for your input!
I feel so ashamed that I have bothered you 😱😱😱... for nothing really .
On Jean-Paul's advice, I wanted to measure the continuity of the connector.
So I remove the frontpanel , and what do I see ???
Someone had put the CO's in reverse.. How stupid can one be...
Yes, it's stupid stupid stupid, hard and embarrassing to admit this, but I want to be honest about it.I also have an explanation for this. We have a cat (Main Koon). But our cat is still playful and loves to use her nails...
So I put the front panels back on as soon as possible, to prevent the cat from damaging the speakers.
But I don't want to blame the cat now either. It's just my own fault. And I'm sorry for all the thinking I've put you through.
But I've learned a lot in the meantime. For example, I also read that it is advisable to renew the capacitors of the CO
These can be purchased from Falcon. A set of 2x5 capacitors.
This could especially make a difference for the mids and highs.
So: again my apologies and thank you all for your input!
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1. Is this the distance you were asking for ? (it's in mm...)
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Nothing to be ashamed of really. We all make mistakes but admitting them is not for everyone so bravo!
What is learned?
1. a systematic approach works
2. keeping track of all steps and doing exactly the same but in reverse order is a preferred method to prevent errors (a few pictures made with a smart phone are excellent tools).
3. human errors are a large factor to take into account so every step should be checked/measured.
4. measuring works, if only to prevent assumptions as the latter create more errors/work
5. the connectors still are questionable so bridging the contacts is a must for optimal performance. Or a better solution must be found.
6. the caps must be replaced. Since they do have an influence care must be taken to make the right choices. Needs attention instead of trusting a company that sells parts.
So the follow up or the "to do" things are 5 and 6.
No, the distance between the holes of the PCB. If these are a standard distance you could solder a connector block to the PCB. Then the wires could be in the screw connectors. In your own pictures in post #23 you can see the holes with the text 'hf", "mf", "+/-" etc. Now, if you are the assumptions type of person the next thing that will go wrong is to assume polarities. If you look at the pictures you will see the pattern is irregular with +/- | -/+ | +/- | -/+. This is also written on the original connector and should be written down just like the colors of the wires going to that pins. When the connector would fit and would be soldered the text is then invisible and I hope you now see what then might go wrong.
What is learned?
1. a systematic approach works
2. keeping track of all steps and doing exactly the same but in reverse order is a preferred method to prevent errors (a few pictures made with a smart phone are excellent tools).
3. human errors are a large factor to take into account so every step should be checked/measured.
4. measuring works, if only to prevent assumptions as the latter create more errors/work
5. the connectors still are questionable so bridging the contacts is a must for optimal performance. Or a better solution must be found.
6. the caps must be replaced. Since they do have an influence care must be taken to make the right choices. Needs attention instead of trusting a company that sells parts.
So the follow up or the "to do" things are 5 and 6.
No, the distance between the holes of the PCB. If these are a standard distance you could solder a connector block to the PCB. Then the wires could be in the screw connectors. In your own pictures in post #23 you can see the holes with the text 'hf", "mf", "+/-" etc. Now, if you are the assumptions type of person the next thing that will go wrong is to assume polarities. If you look at the pictures you will see the pattern is irregular with +/- | -/+ | +/- | -/+. This is also written on the original connector and should be written down just like the colors of the wires going to that pins. When the connector would fit and would be soldered the text is then invisible and I hope you now see what then might go wrong.
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I understand what you mean , Jean-Paul.
Distance between the (8) holes is about 7.5 mm
distance fro the first hole to the last hole is about 53.5 mm
I guess the ALCAP capacitors (Falcon) are a good choice?
KEF CONCERTO REPLACEMENT CAPACITOR SET
Distance between the (8) holes is about 7.5 mm
distance fro the first hole to the last hole is about 53.5 mm
I guess the ALCAP capacitors (Falcon) are a good choice?
KEF CONCERTO REPLACEMENT CAPACITOR SET
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Great! Big relief! Sorry @Galu for overreading your earlier suggestion. But it might have done good to suggest it once more to check for the right orientation of the Xovers.
@Eric: Falcon kits are reliable. I rebuilt the crossovers for my Concertos earlier this year but found that they missed the potential of the drivers. That‘s why Falcon and others offer upgrades for this crossover. They need to be installed inside the box though, so a lot of work.
I built an improved version with aB circuit on the original boards. Their orientation (including that of the plugs) must be changed though. Thread link below.
@Eric: Falcon kits are reliable. I rebuilt the crossovers for my Concertos earlier this year but found that they missed the potential of the drivers. That‘s why Falcon and others offer upgrades for this crossover. They need to be installed inside the box though, so a lot of work.
I built an improved version with aB circuit on the original boards. Their orientation (including that of the plugs) must be changed though. Thread link below.
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Hi I always try to find the best solution technically so I don't bother what others often do as it is mostly based on doing stuff fastest and cheapest like soldering the wires straight to the PCB. So I would not be a customer to buy unspecified caps from a seller too but do the homework myself (with possible consequences of tuning).
I would use terminal blocks like these:
https://www.farnell.com/datasheets/1509394.pdf
But the homework to find a physically fitting type is for you as my time invested in this thread is in the red area. Phoenix is the brand that produces many 7.5 mm pitch connectors blocks either with push contacts or screw contacts. Both are way better than the original connectors. Phoenix stuff is plated copper and not cheap steel stuff. Also notice that you then have to secure the filter by means of extra standoffs. So the challenge is more mechanical.
I won't read all info by eschendorn but it is good to see people have their stuff up to date and can give advice as they own the actual speakers. Just had a quick view but I think you better read that thread and keep to the advice which caps to use. Please note that using even the best caps won't cure the bad contacts of the original crap connectors. Do it once and do it good to enjoy the speakers for many more years.
* please ask the mods to move the thread to "Multi-way" as in is in the wrong subforum. Just click the triangle in the lower left corner to report your own first post. Thank you.
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It‘ true, cleaning the contacts of the connectors had an audibly benign effect, I remember. So that would be the first thing to do.
No problem! There was no criticism of you intended. You were right to ask the question again as it had gone unanswered.
The Falcon Acoustics replacement capacitors are physically 100% compatible with the original black ELCAP types.
And Falcon Acoustics know what they are talking about!
The Falcon B139, B110 and T27 replacement drivers are designed by Malcolm Jones who was the original designer of the KEF drivers! 😎
Not of the caps I hope as any serious tech would have chosen better quality capacitors and connectors 🙂 In fact it is not a recommendation that they're 100% compatible with the old caps! 😀 Just joking, I don't care. I would not buy unspecified stuff as the information is vague in that link whatever blah blah is told.
Side step: I recall those T27 to going defective very fast. Am I right?
Anyway I would keep the schematic by eschendorn in mind when ordering caps. Strangely the caps for the tweeter are bipolar caps of ALCAP fame which I would never use for tweeters. I suspect that the tweeter otherwise is too harsh/loud.
New subject: one could use the best of film caps like NOS MKC or MKP for such small values and do the 47 Ohm 5W metal film resistor trick in parallel to the tweeter. That way the filter works practically the same but the result is better.
Side step: I recall those T27 to going defective very fast. Am I right?
Anyway I would keep the schematic by eschendorn in mind when ordering caps. Strangely the caps for the tweeter are bipolar caps of ALCAP fame which I would never use for tweeters. I suspect that the tweeter otherwise is too harsh/loud.
New subject: one could use the best of film caps like NOS MKC or MKP for such small values and do the 47 Ohm 5W metal film resistor trick in parallel to the tweeter. That way the filter works practically the same but the result is better.
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P.S. Eric, do go ahead and change the capacitors.
Having changed out aged ELCAP electrolytics in other speakers, I can assure you the resulting sound improvement is like night and day - and that's without using expensive replacements!
Your Concertos will sound like the day you bought them.
Improving that original sound is another matter, and the posts in this thread also have that possibility covered for your future reference.
Please report back on your experiences with the recapping.
Having changed out aged ELCAP electrolytics in other speakers, I can assure you the resulting sound improvement is like night and day - and that's without using expensive replacements!
Your Concertos will sound like the day you bought them.
Improving that original sound is another matter, and the posts in this thread also have that possibility covered for your future reference.
Please report back on your experiences with the recapping.