Hi,
In my easy listening room, I have a pair of Kef Concerto's driven by a Kenwood Supreme 500. I love the way they sound, but they have the original crossovers and I'm feeling that they may have deteriorated somewhat since they were manufactured somewhere between 1969 and 1977. Winter is on it's way, and I have decided it is a good time to rebuild the crossovers. I'll put in my ESS AMT 1 mini towers or my Wharfedale Dovedale 3's while the recap is being done.
Now, the question is, do I rebuild the crossovers to the original Kef design, or do I try to emulate the improvements that some say were done by Falcon Accoustics, Wilmslow Audio, or some other design? To be frank, I am looking for your help on this decision.
I will document the full recap with pictures every step of the way.
I really love these speakers, so I want to put in the best components possible to within reason for these beautiful sounding classics.
I've been reading a lot on rebuilding the crossovers on the Concerto's over the last few days. Some say the caps were seriously under rated for the power handling of the drivers. If that is the case, I want to put in higher power components so that I can benefit from the additional output. But I don't want to risk blowing the drivers.
What are your thoughts?
I also don't want to lose the balance between the drivers. As it stands right now, these speakers project beautifully at all volume levels I use in this room. This is where I tend to spend most of my listening to music time and entertaining. I have no plans to modify the cabinets unless they will be hidden changes.
I'm thinking quality caps and aircore inductors, and I also intend to build a whole new circuit board so that I can compare the original with the upgraded crossovers. What recommendations do you have?
Should I follow the schematic specs or the in-unit specs?
In my easy listening room, I have a pair of Kef Concerto's driven by a Kenwood Supreme 500. I love the way they sound, but they have the original crossovers and I'm feeling that they may have deteriorated somewhat since they were manufactured somewhere between 1969 and 1977. Winter is on it's way, and I have decided it is a good time to rebuild the crossovers. I'll put in my ESS AMT 1 mini towers or my Wharfedale Dovedale 3's while the recap is being done.
Now, the question is, do I rebuild the crossovers to the original Kef design, or do I try to emulate the improvements that some say were done by Falcon Accoustics, Wilmslow Audio, or some other design? To be frank, I am looking for your help on this decision.
I will document the full recap with pictures every step of the way.
I really love these speakers, so I want to put in the best components possible to within reason for these beautiful sounding classics.
I've been reading a lot on rebuilding the crossovers on the Concerto's over the last few days. Some say the caps were seriously under rated for the power handling of the drivers. If that is the case, I want to put in higher power components so that I can benefit from the additional output. But I don't want to risk blowing the drivers.
What are your thoughts?
I also don't want to lose the balance between the drivers. As it stands right now, these speakers project beautifully at all volume levels I use in this room. This is where I tend to spend most of my listening to music time and entertaining. I have no plans to modify the cabinets unless they will be hidden changes.
I'm thinking quality caps and aircore inductors, and I also intend to build a whole new circuit board so that I can compare the original with the upgraded crossovers. What recommendations do you have?
Should I follow the schematic specs or the in-unit specs?
I do certainly remember Concertos. Sold many. No need to replace inductors, those don't wear out. Going to "better" caps will change the sound, as they will have less series resistance. I am headed towards a similar re-cap on my Reference 101s, not all that much newer. I'm going to replace with same parts.
I must be a world expert on KEF speakers. Either that or I'm just plain talented, you have hit paydirt anyway...
KEF Concertos:
And the crossover:
I'd replace those tweeter capacitors with 4.7uF polypropylenes:
4 7 fd MKP Capacitor
And those old 104mm mylar tweeters with the excellent Morel CAT 298 soft domes:
Morel Classic CAT298
You could replace those old tired electrolytics on the midrange and bass with new ones like this 80uF:
http://www.wilmslow-audio.co.uk/80-fd-electrolytic-capacitor-559-p.asp
It's always a bit iffy to replace electrolytics with polypropylenes on bass and midrange due to the significant DC resistance of electrolytics that improves damping.
KEF Concertos:
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And the crossover:
An externally hosted image should be here but it was not working when we last tested it.
I'd replace those tweeter capacitors with 4.7uF polypropylenes:
4 7 fd MKP Capacitor
And those old 104mm mylar tweeters with the excellent Morel CAT 298 soft domes:
Morel Classic CAT298
You could replace those old tired electrolytics on the midrange and bass with new ones like this 80uF:
http://www.wilmslow-audio.co.uk/80-fd-electrolytic-capacitor-559-p.asp
It's always a bit iffy to replace electrolytics with polypropylenes on bass and midrange due to the significant DC resistance of electrolytics that improves damping.
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Thanks for the replies. Regarding the audible change in speakers after replacing the caps, there is an excellent thread here about recapping Celestion Ditton 44 speakers.
http://www.diyaudio.com/forums/multi-way/152995-crossover-nightmare-6.html
alan-1-b gave a number of us assistance through the whole process with attention on keeping the original sound. When I did mine, I only recapped one speaker and then listened to the two of them together. Huge difference, although subtle. There was distortion on my original 44 that I didn't hear before until I had one of them recapped. Didn't take me long to recap the other. At that point I listened to the 44s and the Kef's together, and decided I preferred the Kef's over the 44s.
In my case here, I want to keep the original sound as much as possible too. So I am planning on compensating for the lower ESR in the new caps with very small mil resisters following the example in the Crossover Nightmare thread.
I have also read on a thread somewhere in internetlandia that Air Core Inductors also make a big difference.
As for the tweeter, I am planning on keeping the original T27s, at least for now. That may be a project for the future. I absolutely love the bass that these speakers present. Amazing!
One thing I find interestingly different in the Kef Concerto threads versus the Ditton 44 threads is that Kef seemed to keep the same components in their crossovers and Celestion seemed to adjust them with the times. Has anybody seen different cap values than the specs call for?
http://www.diyaudio.com/forums/multi-way/152995-crossover-nightmare-6.html
alan-1-b gave a number of us assistance through the whole process with attention on keeping the original sound. When I did mine, I only recapped one speaker and then listened to the two of them together. Huge difference, although subtle. There was distortion on my original 44 that I didn't hear before until I had one of them recapped. Didn't take me long to recap the other. At that point I listened to the 44s and the Kef's together, and decided I preferred the Kef's over the 44s.
In my case here, I want to keep the original sound as much as possible too. So I am planning on compensating for the lower ESR in the new caps with very small mil resisters following the example in the Crossover Nightmare thread.
I have also read on a thread somewhere in internetlandia that Air Core Inductors also make a big difference.
As for the tweeter, I am planning on keeping the original T27s, at least for now. That may be a project for the future. I absolutely love the bass that these speakers present. Amazing!
One thing I find interestingly different in the Kef Concerto threads versus the Ditton 44 threads is that Kef seemed to keep the same components in their crossovers and Celestion seemed to adjust them with the times. Has anybody seen different cap values than the specs call for?
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I thought I would start the research in advance of actually taking the speakers out of operation until I had a plan going forward. I have two sets of speakers I am considering putting in their place. One set are ESS AMT 1 pedestals, and the other set are Wharfedale Dovedale 3s. They are very different from each other, but the location I will be placing them in is very limiting. It will be interesting which pair I like better in that location.
How did past recap projects on the Concerto deal with the larger capsand positioning them in the cabinets?
How did past recap projects on the Concerto deal with the larger capsand positioning them in the cabinets?
Between the idea and the reality lies THE SHADOW, IIRC. I certainly hope this thread doesn't get as longwinded as that Celestion Ditton 44 thread.
Keep it simple and it is all doable. The reason shunt capacitor ESR matters is it affect phase alignment greatly. So don't mess with it.
You don't have much room on the circuit board for huge changes. Do bear in mind that newer lead-free solder needs a hot iron and some quick work.
Speakers aren't hard if you have a clear mind. I would confine myself to upgrading the top end here, as mentioned earlier, along with renewing dried-out electrolytics elsewhere. That treble filter IS a bit messy. It would be more usual to use a 4uF and a 12uF for a smoother rolloff. 4.7uF/4.7uF is a bit peaky, but may be a zingy treble sound you like.
3-Way Classic
The Morel CAT 298 is considered a slot in replacement. I don't know if it'll need attenuation or a 7.5R/1uF Zobel at this stage. Probably not. 250V polypropylene would seem to be much easier than bigger 630V types too.
Keep it simple and it is all doable. The reason shunt capacitor ESR matters is it affect phase alignment greatly. So don't mess with it.
You don't have much room on the circuit board for huge changes. Do bear in mind that newer lead-free solder needs a hot iron and some quick work.
Speakers aren't hard if you have a clear mind. I would confine myself to upgrading the top end here, as mentioned earlier, along with renewing dried-out electrolytics elsewhere. That treble filter IS a bit messy. It would be more usual to use a 4uF and a 12uF for a smoother rolloff. 4.7uF/4.7uF is a bit peaky, but may be a zingy treble sound you like.
3-Way Classic
The Morel CAT 298 is considered a slot in replacement. I don't know if it'll need attenuation or a 7.5R/1uF Zobel at this stage. Probably not. 250V polypropylene would seem to be much easier than bigger 630V types too.
Attachments
,
I agree....just do the tweeter filter (4.7uF + 4.7uF, and/or try the 4uF + 12uF as suggested also), and then the mid filter.
For the mid two 15uF in parallel and a 4.7//2.2 uF for the 7 uF cap.
I would use 100V Polypropylene caps..higher voltage get too big and too expensive, and you wont need higher voltage rating in this application.
I have heard Concertos done this way and the result works out quite fine.
Dan.
Crossover nightmare
I appreciate your input system7, but that thread was invaluable to myself and many others. The only reason I was willing to attempt a cap replacement on my Ditton 44s was due to the detailed explanations from alan-1-b and many others. It had been many years since I had used a soldering iron, and then only on digital circuits. To be frank, analog has always mystified me. alan-1-b gave detailed explanations that gave me the confidence to approach the task of recapping my speakers.
Following your last post, I went on the Internet and did a search on the tweeter you mention. I found a number of threads that provided insight to me on tweeter replacements, in the unfortunate situation where I might find myself replacing my T27s if disaster were to occur, but I really hope that never happens. I really do love the balance and tone of the Concerto's. These are very special speakers in my eyes. My personal opinion is that the people who have suffered from tweeter failure in their Kef T27s are a result of clipping. I have come to this conclusion as a result of testing many speakers and amplifiers over the last year in many different places. I have heard the differences of an underpowered speaker, and then a properly driven speaker and when it is underpowered, I find the highs are shrill to the point of hurting my ears, and the bass seems uncontrolled. I was originally driving my Kefs with a hefty MAC1900 and both my Ditton 44s and my Concerto's sounded harsh if I turned the volume higher. Now, I regularly turn my Kenwood Supreme to louder volume levels than my MAC1900, with no harshness or uncontrolled bass at all. Hopefully, I won't be eating my words for this statement.
The concerto's like lots of current to sound their best. It may also help that I am driving them with a Kenwood Supreme 500. It has been described as having a "tube like" sound, and I have to agree, never having owned a Tube Amp.
Speaking of alan-1-b, I sincerely hope he drops over to this thread to provide his insight. When I completed the recap on my ditton 44s, I got into a few private messages with Alan over my intent to recap my Kef Concerto's.
With his permission, here is an excerpt from the correspondence.
Between the idea and the reality lies THE SHADOW, IIRC. I certainly hope this thread doesn't get as longwinded as that Celestion Ditton 44 thread.
I appreciate your input system7, but that thread was invaluable to myself and many others. The only reason I was willing to attempt a cap replacement on my Ditton 44s was due to the detailed explanations from alan-1-b and many others. It had been many years since I had used a soldering iron, and then only on digital circuits. To be frank, analog has always mystified me. alan-1-b gave detailed explanations that gave me the confidence to approach the task of recapping my speakers.
Following your last post, I went on the Internet and did a search on the tweeter you mention. I found a number of threads that provided insight to me on tweeter replacements, in the unfortunate situation where I might find myself replacing my T27s if disaster were to occur, but I really hope that never happens. I really do love the balance and tone of the Concerto's. These are very special speakers in my eyes. My personal opinion is that the people who have suffered from tweeter failure in their Kef T27s are a result of clipping. I have come to this conclusion as a result of testing many speakers and amplifiers over the last year in many different places. I have heard the differences of an underpowered speaker, and then a properly driven speaker and when it is underpowered, I find the highs are shrill to the point of hurting my ears, and the bass seems uncontrolled. I was originally driving my Kefs with a hefty MAC1900 and both my Ditton 44s and my Concerto's sounded harsh if I turned the volume higher. Now, I regularly turn my Kenwood Supreme to louder volume levels than my MAC1900, with no harshness or uncontrolled bass at all. Hopefully, I won't be eating my words for this statement.
The concerto's like lots of current to sound their best. It may also help that I am driving them with a Kenwood Supreme 500. It has been described as having a "tube like" sound, and I have to agree, never having owned a Tube Amp.
Speaking of alan-1-b, I sincerely hope he drops over to this thread to provide his insight. When I completed the recap on my ditton 44s, I got into a few private messages with Alan over my intent to recap my Kef Concerto's.
With his permission, here is an excerpt from the correspondence.
alan-1-b said:
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My neighbour in London used to run KEF Concertos along with Quad amplification. I fixed them up for him one day back in the eighties. He wondered what I had done that so improved matters. In fact I had just cleaned up the tarnished connectors. We were enjoying Paul Simon's "Graceland" on them as I recall.
For all that, I always found bextrene and mylar drivers dull and recessed sounding, albeit polite and smooth. I have a pair of soft silk dome ferrofluid Morel CAT 298 tweeters running in one of my projects currently, and they are remarkably good and smooth. We used them in Mr. Ives' repair KEF Cresta projects to good effect:
http://www.diyaudio.com/forums/multi-way/214983-t27-tweeter-replacement-kef-cresta-1968-a.html
He blogged it all here:
mending things: Kef Cresta speaker renovation
It's my personal opinion that people get too prissy about restore projects, paying huge sums on eBay for old driver replacements. The KEF T27 and Celestion HF 2000 weren't all that good really. Just the best around at the time. The Concerto's doubtless like amps with good current reserves being heavy reflex bass units, that's how it works.
For all that, I always found bextrene and mylar drivers dull and recessed sounding, albeit polite and smooth. I have a pair of soft silk dome ferrofluid Morel CAT 298 tweeters running in one of my projects currently, and they are remarkably good and smooth. We used them in Mr. Ives' repair KEF Cresta projects to good effect:
http://www.diyaudio.com/forums/multi-way/214983-t27-tweeter-replacement-kef-cresta-1968-a.html
He blogged it all here:
mending things: Kef Cresta speaker renovation
It's my personal opinion that people get too prissy about restore projects, paying huge sums on eBay for old driver replacements. The KEF T27 and Celestion HF 2000 weren't all that good really. Just the best around at the time. The Concerto's doubtless like amps with good current reserves being heavy reflex bass units, that's how it works.
Vintage audio is new to me, although I loved that kind of equipment growing up. The realities at the time were that I couldn't afford any of this stuff then, being young, and then young and in a relationship, and then young with 3 kids. I had to wait until my kids grew up before I returned to this passion.
I agree, the Concerto's do sound a little dull at first after listening to Celestion Ditton's. However it doesn't take long to realize it isn't dull at all. It is just your ears tuning to a different ... feeling? I ended up picking the Kef's over the Dittons. And I have listened to many many other different speakers since. I am cursed with the golden ear, and the majority of speakers I've listened to don't sound anything special. I have also had the pleasure of listening to some really excellent speakers. Top of the line Missions, Polk SBAs, and Sound Lab A-3s! The A3s were astounding! However, I have to be realistic, and the A3s are way out of my league.
And I love the sound and look of vintage audio.
I did read that thread. It was quite interesting, and I went on to look at the Mr. Ives site. I think it was that one anyway. Sometimes I read way too much way too quickly and get confused on what I've read and where it came from. Another part of the fun is the research!
Has anyone seen any Concerto crossovers that were different from the schematics? Just curious if they did adjustments like Celestion did in their crossovers..
I agree, the Concerto's do sound a little dull at first after listening to Celestion Ditton's. However it doesn't take long to realize it isn't dull at all. It is just your ears tuning to a different ... feeling? I ended up picking the Kef's over the Dittons. And I have listened to many many other different speakers since. I am cursed with the golden ear, and the majority of speakers I've listened to don't sound anything special. I have also had the pleasure of listening to some really excellent speakers. Top of the line Missions, Polk SBAs, and Sound Lab A-3s! The A3s were astounding! However, I have to be realistic, and the A3s are way out of my league.
And I love the sound and look of vintage audio.
I did read that thread. It was quite interesting, and I went on to look at the Mr. Ives site. I think it was that one anyway. Sometimes I read way too much way too quickly and get confused on what I've read and where it came from. Another part of the fun is the research!
Has anyone seen any Concerto crossovers that were different from the schematics? Just curious if they did adjustments like Celestion did in their crossovers..
Unless you are a filter specialist, these may not mean a lot to you, but KEF did much more complex things when they used computer modelling on filters. I think they were getting a bit too obsessed with perfecting/flattening their curves really. Lynn Olson talks bout this stuff:
The Art of Speaker Design
The KEF R101 was the best small speaker KEF made at the time. Almost LS3/5A in concept. The KEF 104AB (acoustic butterworth) used the 8" bass unit.
Bigger improvements were found by Spendor and Harbeth with more advanced speaker materials IMO.
The Art of Speaker Design
The KEF R101 was the best small speaker KEF made at the time. Almost LS3/5A in concept. The KEF 104AB (acoustic butterworth) used the 8" bass unit.
Bigger improvements were found by Spendor and Harbeth with more advanced speaker materials IMO.
Attachments
I can read them no problem, but no, I am not a filter specialist. Just learning. The second looks like the 104aB filter network. I used to have a pair of these, but I much preferred the Concerto's. I know they aren't the best, but I just really like how they sound. Interestingly, I found the 104aB's complimented the Concerto's, only the Concerto's have a much deeper bass! Much deeper! Most music types shine on these speakers, even Hip Hop!
I have very eclectic music tastes.
I also have a pair of ESS AMT 1aM towers, and they are influencing me a great deal. I first got a pair of ESS AMT 1 pedestals (10 inch Alnico bass reflex ported out the back) and I loved that Heil Transformer! I then auditioned the 1aM towers and found my sound. These speakers are awesome! They aren't perfect, and a future project of mine will be to tweak their sound more to my liking, but my obsession with finding that 'sound' stopped when I bought them. I also love the way they look. The imaging and the sound field is superb, and the clarity and airiness of the mids to highs is very addicting!
And I still love my Concerto's...
I have very eclectic music tastes.
I also have a pair of ESS AMT 1aM towers, and they are influencing me a great deal. I first got a pair of ESS AMT 1 pedestals (10 inch Alnico bass reflex ported out the back) and I loved that Heil Transformer! I then auditioned the 1aM towers and found my sound. These speakers are awesome! They aren't perfect, and a future project of mine will be to tweak their sound more to my liking, but my obsession with finding that 'sound' stopped when I bought them. I also love the way they look. The imaging and the sound field is superb, and the clarity and airiness of the mids to highs is very addicting!
And I still love my Concerto's...
Picture of my living room with Concerto's
This photo shows, although very poorly, my living room layout with the Kef's. As you can see, I am very limited in speaker placement. I have my 4 year old grand son living with me, so I can't leave the speakers in an exposed area. Behind the side tables is the safest.
This photo shows, although very poorly, my living room layout with the Kef's. As you can see, I am very limited in speaker placement. I have my 4 year old grand son living with me, so I can't leave the speakers in an exposed area. Behind the side tables is the safest.
Attachments
I must be a world expert on KEF speakers. Either that or
I'm just plain talented, you have hit paydirt anyway...
Hi,
Or just deluded and overrating your opinionated "knowledge".
I think its fair to say your expertise doesn't match your opinion.
rgds, sreten.
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Last night I pulled my Kef Concerto's from their home over the last 10 months and put my ESS AMT 1's in their place. Interesting how the character of the sound changed for the AMTs from being in the middle of the room, to being stuck in the corners. No flexibility on where I can place them. I now notice how little midrange the AMTs have. I guess before, with the bass being less emphasized, the lack of mids didn't stand out.
Don't get me wrong. They sound very good, but nearly as good as the concerto's in that same place. I placed some concrete slabs underneath them. Not sure if that was a good thing or not, but I am not about to take them out now. It is a pain to get there.
The Kef's are Bass reflex ported to the front, and the AMTs are Bass reflex ported at the bottom rear. I'm not really surprised that the Kefs outperform the AMTs in that location just because with a front ported speaker, being placed in the corners has less of an impact to the sound. At least that is why I think it is like that.
Next week I will be starting on the Kef's.
Don't get me wrong. They sound very good, but nearly as good as the concerto's in that same place. I placed some concrete slabs underneath them. Not sure if that was a good thing or not, but I am not about to take them out now. It is a pain to get there.
The Kef's are Bass reflex ported to the front, and the AMTs are Bass reflex ported at the bottom rear. I'm not really surprised that the Kefs outperform the AMTs in that location just because with a front ported speaker, being placed in the corners has less of an impact to the sound. At least that is why I think it is like that.
Next week I will be starting on the Kef's.
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Those crossovers show 2 unique features that KEF pioneered. The bridged T of the tweeter was integral to the Acoustic Butterworth approach. It allowed a controllable notch in the tweeter drive that let you get a combination of electrical and acoustical that were still straight Butterworth rather than having a strong inflection point in the curve at the electrical resonance.
The series capacitance was part of the overall LF shaping. The rule of thumb was to start with a sealed box with an overall Q of 0.9 and size the capacitors to create a flat third order. Works quite well and actually flattens and extends response slightly, plus helps power handling.
The R101 was meant to be an "LS3/5a done right" but it never had the prominance in the market that the BBC unit had. A couple of years later we redesigned the LS3/5a, but that is another story.
David S
Always enjoy discussions with you, speaker dave. For people who don't know, Dave used to work for KEF and is rather knowledgeable about them.
I have been dabbling with some vintage 8" bextrene plus 1" tweeter Audiomaster MLS4 jobbies lately, designed by Robin Marshall in THE TRADITION apparently:
Are these speakers worth refurbing? - Page 8
The whole plastic cone thing is fascinating. Joachim Gerhard likes metal and reed cones currently, rightly pointing out that they have about a third of the stored energy, but for all that a LOT of people like heavily damped cones. It's almost like you either build the damping into the crossover or into the drive unit. You're going to need it one way or another for the smooth, sweet sound.
Students of plastic cones might also find these pages interesting. Rogers speakers which were using polypropylene cones IIRC, superbly documented by Mark Hennessy:
Rogers Speakers - BBC LS5/9
TechnoDweeb mentioned he liked the Concerto's. 3-ways just work better than 2-ways for various reasons, the main ones being that the mid is spared excursion into non-linearity and dispersion is better in the midrange.
I have been dabbling with some vintage 8" bextrene plus 1" tweeter Audiomaster MLS4 jobbies lately, designed by Robin Marshall in THE TRADITION apparently:
Are these speakers worth refurbing? - Page 8
The whole plastic cone thing is fascinating. Joachim Gerhard likes metal and reed cones currently, rightly pointing out that they have about a third of the stored energy, but for all that a LOT of people like heavily damped cones. It's almost like you either build the damping into the crossover or into the drive unit. You're going to need it one way or another for the smooth, sweet sound.
Students of plastic cones might also find these pages interesting. Rogers speakers which were using polypropylene cones IIRC, superbly documented by Mark Hennessy:
Rogers Speakers - BBC LS5/9
TechnoDweeb mentioned he liked the Concerto's. 3-ways just work better than 2-ways for various reasons, the main ones being that the mid is spared excursion into non-linearity and dispersion is better in the midrange.
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TechnoDweeb
I updated the crossovers on Kef 104'4, Concerto's and on the 101/2 some time ago.
I discussed with Kef ( they were still around then ) the possibility of replacing the electrolytic capacitors in the mid and treble sections with plastic capacitors. Kef replied that the Kef crossover calculations took account of the electrolytic capacitors series resistence and good electrolytics were recomended by Kef as the replacements. If I changed from electrolytic to plastic capacitor then I was advised to add a resistor in series with each changed capacitor. The value being 1 ohm per 10uf of capacitor. I did that and it worked well.
If you do not include the extra resistors I imagine you will change the crossover frequency/profile.
Don
I updated the crossovers on Kef 104'4, Concerto's and on the 101/2 some time ago.
I discussed with Kef ( they were still around then ) the possibility of replacing the electrolytic capacitors in the mid and treble sections with plastic capacitors. Kef replied that the Kef crossover calculations took account of the electrolytic capacitors series resistence and good electrolytics were recomended by Kef as the replacements. If I changed from electrolytic to plastic capacitor then I was advised to add a resistor in series with each changed capacitor. The value being 1 ohm per 10uf of capacitor. I did that and it worked well.
If you do not include the extra resistors I imagine you will change the crossover frequency/profile.
Don
I'm a bit behind on this project...
Thank you very much Don. That is very interesting. I was aware of the difference in ESR, but I never knew how they calculate it.
Well, once again, I am behind on my project, and I haven't even started it yet! It seems I keep spending too much money on equipment, and have none left for my projects. Right around the time I was planning on starting this, I got a call from my Audio Tech, and he had finished restoring my Bose 1801. I bought this unit in February as a dead unit, and it has been in his hands ever since. In the meantime, I was able to locate the 4401 preamp, that came with an 1801. So now I have my first 1801 back, and there is a really big difference between it and the 1801 I got in the summer. Amazing, the way my ESS AMT 1aM towers just disappear! I love it! So I have been listening to my collection all over again, in between building Lego creatures with my grandson and searching for cool bargains at thrift stores, estate sales, and on kijiji. Unfortunately, that eats up my spending money for parts and my time as I clean the cool things I've found.
I need to sell some of it. I'm trying, but the market seems to have slowed down, or maybe I have an inflated view of the value of these things. Anyway, it looks like this project will be on a pause until after Christmas. I'm getting back on track though.
Stay tuned....
Thank you very much Don. That is very interesting. I was aware of the difference in ESR, but I never knew how they calculate it.
Well, once again, I am behind on my project, and I haven't even started it yet! It seems I keep spending too much money on equipment, and have none left for my projects. Right around the time I was planning on starting this, I got a call from my Audio Tech, and he had finished restoring my Bose 1801. I bought this unit in February as a dead unit, and it has been in his hands ever since. In the meantime, I was able to locate the 4401 preamp, that came with an 1801. So now I have my first 1801 back, and there is a really big difference between it and the 1801 I got in the summer. Amazing, the way my ESS AMT 1aM towers just disappear! I love it! So I have been listening to my collection all over again, in between building Lego creatures with my grandson and searching for cool bargains at thrift stores, estate sales, and on kijiji. Unfortunately, that eats up my spending money for parts and my time as I clean the cool things I've found.
I need to sell some of it. I'm trying, but the market seems to have slowed down, or maybe I have an inflated view of the value of these things. Anyway, it looks like this project will be on a pause until after Christmas. I'm getting back on track though.
Stay tuned....
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