What follows is not meant to be any kind of definitive statement on the Proac Response 2.5 clone, and I certainly don't claim to have "golden ears". In fact, I am firmly of the opinion that every speaker is a balance of strengths and weaknesses, and personal preferences and tolerances decide what we can or can't live with. A speaker can be "great", and we can recognise it as such - but there may still be things about it that lead to reservations. So, I hope any criticism I make of the 2.5 clone will be seen in that context.
I completed my clones back in August of last year. In fact, I still haven't lacquered the veneer - I just couldn't wait to hear them. Knowing they were renowned for their bass response, I tentatively tried a couple of recordings I knew would show what they could do in the lower end. My jaw dropped. The door to my room was rattling against its frame and I was feeling - not just hearing - bass notes from that tiny mid-woofer! Strangely enough given others' experiences, the bass seemed all there from the start; what occurred during the break-in period was that it tightened up markedly. At first, I found it was necessary to reduce the diameter of the port to prevent boominess becoming a problem, but after the first month I was able to restore the original diameter and was left with beautiful, tight, incredibly deep and tuneful lows. Remarkable!
All was not well elsewhere, however. I was disappointed to hear an intolerable glare on vocals, strings and brass, accompanied by rather excessive sibilance. On a very few recordings, it sounded great, but as for the rest . . . Ah well, I thought, the drivers are new and they have to break in. I played the clones almost constantly for many weeks, and there was only a marginal improvement in these areas, though they did develop more "body" and the tighter bass. I rechecked the crossover layout (constructed with Jacq's mods, 12 gauge inductors and high-quality polypropylene caps), tried different cables, amps and source components, but the problems remained. Scouring the Web, I found no reference to what I was hearing until I found some measurements and a report from Dennis Murphy on the Madisound forum to the effect that there was still a marked peak at 2 KHz, and it was clearly audible. That was kind of a relief in the circumstances!
I was desperate to try anything, and heard about the series crossover on http://audioclone.free.fr. I tried it and, voila, the glare was gone! In fact, I was so impressed by that one fact that it blinded me to the very real shortcomings of this crossover. As Troels Gravesen has shown in his excellent paper at http://members.chello.se/jpo/2_5_clone_measurements_v5.pdf, the series crossover has a far from acceptable frequency response and serious phase problems - and, yes, when compared with Troels' own mods to the parallel crossover, those faults are clearly audible. Nevertheless, despite its massive unevenness, I think this circuit does exhibit some of the subjective advantages of the series approach, and I still hope it will be developed further - though I suspect it would be a daunting task to adequately correct for the response anomalies of this combination of drivers with a series crossover.
At the same time, Troels introduced in his paper the initial version of his 2 KHz notch filter for the Jacq-modded crossover, together with an impressive set of measurements. What a revelation! Now I could understand what all the fuss was about with the clone! The midrange smoothed out, there was more space and depth, and it was possible to grasp what was really meant by that Proac "magic". This was one mighty impressive speaker, and for a while I was content to explore my vinyl and CD collections. The problem was that the sometimes excessive sibilance remained, and as time went on I started to realise that all was still not well in the midrange (more on that later).
Also, I agree with those who have reported a lack of lower midrange/upper bass energy. As it says in the "Stereophile" review, this is certainly caused by a room boundary problem due to the height of the woofer above floor level. I have tried the speaker in three different rooms and spent hours experimenting with positioning, but the problem can only be minimised, not eliminated. If a recording lacks energy in this area, the clone can sound too "dry". This is far more obvious with solid state than valves, so if you're going to use a solid state amp, my opinion is: choose one with an uncharacteristically warm midrange. I use a Dynaco PAS3X/Stereo 70 valve preamp and amp most of the time. My lovely old, warm-sounding Sugden C51/P51 solid state combo also works well. Still, the tendency is always there - depending on the recording.
Troels has since introduced his own tweaks to the basic crossover, with arguably further improvement. The midrange is a little cleaner, and I find the sibilance problem is also better dealt with. Vocals are more natural as a result. Nevertheless, to my ears his latest version marks a slight move away from the appealing "technicolour" sound of the clone. I found that I needed to reduce the tweeter attenuating resistor back to 5 ohms (Troels recommends 5.6 ohms) in order to restore that Proac magic to the sound. In the most recent revision of his paper, Troels has changed his recommendation to 8.2 ohms for this resistor. His measurements show an impressively flat response - but in the context of my system, reducing the highs to this level simply saps the life from the speaker, making it dull and uninteresting with diminished detail. (Troels is using a solid state amp, so this may explain the difference in what we hear.) However, this reduction does deal well with the sibilance problem.
Reducing tweeter output also shows that all is still not well at the top end of the mid-woofer's response, especially with vocals, Breaking through all the lush smoothness and transparency, there is still a slight but definite hard edge, together with a sound that is not as clean as it could be. I think the highs need to be kept slightly elevated in order to mask this. Nevertheless, this highlights my main problem with the clones. The tweeter's tendency to sibilance and the remaining problems in the midrange make this a very fussy speaker - of amplification, of source components and, most of all, of recording quality and balance. I find that as time has gone on, I am avoiding a fair amount of the music I once enjoyed. If everything in a recording suits the clones, listening is a treat. If not . . .
Now some may argue that the clones are simply being honest to the source, but I can't totally accept that. I do think that much can be explained by the fact that both tweeter and mid-woofer are operating at the very extremes of their working ranges around the crossover point. The "nasties" I hear from the 8535 sound very much like cone break-up to me. (Incidentally, Troels has recently identified a 3 KHz peak resulting from resonance in the 8535's dust cap, and is experimenting with damping techniques.)
Now, before the flak starts coming in, I want to reiterate that I do consider the clone a great speaker, and I still enjoy it much of the time. The problem is that it is so good in so many areas that I have found it increasingly harder to forgive its few faults - a real love/hate relationship! My experience has been that as the initial attraction and wonder wear off, those faults become harder and harder to live with - and I have done a lot of listening since last commenting (I think rather prematurely) in this forum. However . . . and it's a big "however", I do my listening with my ears and no-one else's. What one person finds intolerable or irritating, another may not even notice, so please don't be put off by anything I've said.
My own advice to prospective clone-builders is to seek out the commercial Response 2.5 if you can find it, and have a long, hard listen before you embark on this project. Preferably, you should hear it with your own amp and source equipment, and a selection of your favourite recordings. In my opinion, this is a highly idiosyncratic speaker, and may not suit everyone.
In conclusion, I would like to thank Al.M, Jacq, Troels and all others who have contributed to this project for all their hard work. They have made this quite an adventure!
I completed my clones back in August of last year. In fact, I still haven't lacquered the veneer - I just couldn't wait to hear them. Knowing they were renowned for their bass response, I tentatively tried a couple of recordings I knew would show what they could do in the lower end. My jaw dropped. The door to my room was rattling against its frame and I was feeling - not just hearing - bass notes from that tiny mid-woofer! Strangely enough given others' experiences, the bass seemed all there from the start; what occurred during the break-in period was that it tightened up markedly. At first, I found it was necessary to reduce the diameter of the port to prevent boominess becoming a problem, but after the first month I was able to restore the original diameter and was left with beautiful, tight, incredibly deep and tuneful lows. Remarkable!
All was not well elsewhere, however. I was disappointed to hear an intolerable glare on vocals, strings and brass, accompanied by rather excessive sibilance. On a very few recordings, it sounded great, but as for the rest . . . Ah well, I thought, the drivers are new and they have to break in. I played the clones almost constantly for many weeks, and there was only a marginal improvement in these areas, though they did develop more "body" and the tighter bass. I rechecked the crossover layout (constructed with Jacq's mods, 12 gauge inductors and high-quality polypropylene caps), tried different cables, amps and source components, but the problems remained. Scouring the Web, I found no reference to what I was hearing until I found some measurements and a report from Dennis Murphy on the Madisound forum to the effect that there was still a marked peak at 2 KHz, and it was clearly audible. That was kind of a relief in the circumstances!
I was desperate to try anything, and heard about the series crossover on http://audioclone.free.fr. I tried it and, voila, the glare was gone! In fact, I was so impressed by that one fact that it blinded me to the very real shortcomings of this crossover. As Troels Gravesen has shown in his excellent paper at http://members.chello.se/jpo/2_5_clone_measurements_v5.pdf, the series crossover has a far from acceptable frequency response and serious phase problems - and, yes, when compared with Troels' own mods to the parallel crossover, those faults are clearly audible. Nevertheless, despite its massive unevenness, I think this circuit does exhibit some of the subjective advantages of the series approach, and I still hope it will be developed further - though I suspect it would be a daunting task to adequately correct for the response anomalies of this combination of drivers with a series crossover.
At the same time, Troels introduced in his paper the initial version of his 2 KHz notch filter for the Jacq-modded crossover, together with an impressive set of measurements. What a revelation! Now I could understand what all the fuss was about with the clone! The midrange smoothed out, there was more space and depth, and it was possible to grasp what was really meant by that Proac "magic". This was one mighty impressive speaker, and for a while I was content to explore my vinyl and CD collections. The problem was that the sometimes excessive sibilance remained, and as time went on I started to realise that all was still not well in the midrange (more on that later).
Also, I agree with those who have reported a lack of lower midrange/upper bass energy. As it says in the "Stereophile" review, this is certainly caused by a room boundary problem due to the height of the woofer above floor level. I have tried the speaker in three different rooms and spent hours experimenting with positioning, but the problem can only be minimised, not eliminated. If a recording lacks energy in this area, the clone can sound too "dry". This is far more obvious with solid state than valves, so if you're going to use a solid state amp, my opinion is: choose one with an uncharacteristically warm midrange. I use a Dynaco PAS3X/Stereo 70 valve preamp and amp most of the time. My lovely old, warm-sounding Sugden C51/P51 solid state combo also works well. Still, the tendency is always there - depending on the recording.
Troels has since introduced his own tweaks to the basic crossover, with arguably further improvement. The midrange is a little cleaner, and I find the sibilance problem is also better dealt with. Vocals are more natural as a result. Nevertheless, to my ears his latest version marks a slight move away from the appealing "technicolour" sound of the clone. I found that I needed to reduce the tweeter attenuating resistor back to 5 ohms (Troels recommends 5.6 ohms) in order to restore that Proac magic to the sound. In the most recent revision of his paper, Troels has changed his recommendation to 8.2 ohms for this resistor. His measurements show an impressively flat response - but in the context of my system, reducing the highs to this level simply saps the life from the speaker, making it dull and uninteresting with diminished detail. (Troels is using a solid state amp, so this may explain the difference in what we hear.) However, this reduction does deal well with the sibilance problem.
Reducing tweeter output also shows that all is still not well at the top end of the mid-woofer's response, especially with vocals, Breaking through all the lush smoothness and transparency, there is still a slight but definite hard edge, together with a sound that is not as clean as it could be. I think the highs need to be kept slightly elevated in order to mask this. Nevertheless, this highlights my main problem with the clones. The tweeter's tendency to sibilance and the remaining problems in the midrange make this a very fussy speaker - of amplification, of source components and, most of all, of recording quality and balance. I find that as time has gone on, I am avoiding a fair amount of the music I once enjoyed. If everything in a recording suits the clones, listening is a treat. If not . . .
Now some may argue that the clones are simply being honest to the source, but I can't totally accept that. I do think that much can be explained by the fact that both tweeter and mid-woofer are operating at the very extremes of their working ranges around the crossover point. The "nasties" I hear from the 8535 sound very much like cone break-up to me. (Incidentally, Troels has recently identified a 3 KHz peak resulting from resonance in the 8535's dust cap, and is experimenting with damping techniques.)
Now, before the flak starts coming in, I want to reiterate that I do consider the clone a great speaker, and I still enjoy it much of the time. The problem is that it is so good in so many areas that I have found it increasingly harder to forgive its few faults - a real love/hate relationship! My experience has been that as the initial attraction and wonder wear off, those faults become harder and harder to live with - and I have done a lot of listening since last commenting (I think rather prematurely) in this forum. However . . . and it's a big "however", I do my listening with my ears and no-one else's. What one person finds intolerable or irritating, another may not even notice, so please don't be put off by anything I've said.
My own advice to prospective clone-builders is to seek out the commercial Response 2.5 if you can find it, and have a long, hard listen before you embark on this project. Preferably, you should hear it with your own amp and source equipment, and a selection of your favourite recordings. In my opinion, this is a highly idiosyncratic speaker, and may not suit everyone.
In conclusion, I would like to thank Al.M, Jacq, Troels and all others who have contributed to this project for all their hard work. They have made this quite an adventure!
Nadir,
I think you pretty well described the sonic character of the clone. I have also built one and when first hooked up the drivers with the XO in a scrappy box i was also amazed on how nice it sounds.
Later on in the Proac box, after many hours of listening I also started to discover the weaknesses.
Even with the 2Khz bump present the midrange seemed somewhat recessed and the highs were overemphasized, so that is the sibilance you are referring to.
I think Troels made enermous effort to linearize the reponse and make the XO better , but didn't address the main point in the HF filter.
With this type of network topology there always will be a slightly rising response from 5Khz to 10 Khz and onward. It is about +2-3dB at 10Khz and i think it is partially repsonsible for the sibilance.
I have modified the HF part, so that left out the 5 and 47ohm resistors and placed a normal L pad between the LC network and the tweeter.
In my opinion it is much better now and I have no problems with the sibillance.
I am not saying that is perfect now and probably it will never be, because of the tweeter, but I think the XO still can be made better and not necessarily by replacing the tweeter.
I will probably publish this mod on my website when will have some time.
Zozo
http://diyproac25.fw.hu
I think you pretty well described the sonic character of the clone. I have also built one and when first hooked up the drivers with the XO in a scrappy box i was also amazed on how nice it sounds.
Later on in the Proac box, after many hours of listening I also started to discover the weaknesses.
Even with the 2Khz bump present the midrange seemed somewhat recessed and the highs were overemphasized, so that is the sibilance you are referring to.
I think Troels made enermous effort to linearize the reponse and make the XO better , but didn't address the main point in the HF filter.
With this type of network topology there always will be a slightly rising response from 5Khz to 10 Khz and onward. It is about +2-3dB at 10Khz and i think it is partially repsonsible for the sibilance.
I have modified the HF part, so that left out the 5 and 47ohm resistors and placed a normal L pad between the LC network and the tweeter.
In my opinion it is much better now and I have no problems with the sibillance.
I am not saying that is perfect now and probably it will never be, because of the tweeter, but I think the XO still can be made better and not necessarily by replacing the tweeter.
I will probably publish this mod on my website when will have some time.
Zozo
http://diyproac25.fw.hu
Dan:
The clone's crossover has evolved and improved dramatically, but I think we are probably reaching the limits on what can be done, given the nature of the drivers. Even with 18dB/octave slopes and the notch filter, it is a big ask to cross a mid-woofer of the 8535's diameter over to a 19mm tweeter like the 8513 and not expect some problems in the crossover region. In fact, all things considered, the combination works far better that one might expect. While there may well be more small improvements via xo tweaks, I suspect mechanical damping (through coating of the 8535) will be the main direction as the clone evolves in the future. Just don't be tempted to experiment with this yourself - leave it to guys like Troels. You could easily wreck your drivers! There will probably be more news on this shortly.
Zozo:
Glad you agree! It's worth noting that the 8513 - good though it is - is not Scan-Speak's best tweeter. Another direction future development may take is its replacement by something like the Hiquphon OW1, but this would require a radical xo redesign. It will be interesting to see what happens.
The clone's crossover has evolved and improved dramatically, but I think we are probably reaching the limits on what can be done, given the nature of the drivers. Even with 18dB/octave slopes and the notch filter, it is a big ask to cross a mid-woofer of the 8535's diameter over to a 19mm tweeter like the 8513 and not expect some problems in the crossover region. In fact, all things considered, the combination works far better that one might expect. While there may well be more small improvements via xo tweaks, I suspect mechanical damping (through coating of the 8535) will be the main direction as the clone evolves in the future. Just don't be tempted to experiment with this yourself - leave it to guys like Troels. You could easily wreck your drivers! There will probably be more news on this shortly.
Zozo:
Glad you agree! It's worth noting that the 8513 - good though it is - is not Scan-Speak's best tweeter. Another direction future development may take is its replacement by something like the Hiquphon OW1, but this would require a radical xo redesign. It will be interesting to see what happens.
First of all, thank you Nadir and the ProAc cloners for their testing and posts on the forum.
I've been reading about everyone's experiences and I must say, I'm still a bit confused about what builders consider the Proac's main weakness. That is, the speaker's 2 Khz peak.
Nadir says he is "disappointed to hear an intolerable glare on vocals, strings and brass, accompanied by rather excessive sibilance." This blows my mind given that the 2.5 cost $4500, and for any of its properties to be intolerable is pretty insane. Simiarly, Proacs really excel when driven by tubes, but for $4500 it better sound great on any equipment! Nadir, are you judging in relative terms?
Secondly, I think the LCR filter for the 2.5 is widely approved by cloners. I recall someone asking why ProAc didn't just include an LCR filter if it made a big difference, without getting a reply. Can someone comment on this? It will give confidence to future cloners knowing that that a basic 2.5 clone will sound amazing, and by adding the LCR, it sounds even better!
I've been reading about everyone's experiences and I must say, I'm still a bit confused about what builders consider the Proac's main weakness. That is, the speaker's 2 Khz peak.
Nadir says he is "disappointed to hear an intolerable glare on vocals, strings and brass, accompanied by rather excessive sibilance." This blows my mind given that the 2.5 cost $4500, and for any of its properties to be intolerable is pretty insane. Simiarly, Proacs really excel when driven by tubes, but for $4500 it better sound great on any equipment! Nadir, are you judging in relative terms?
Secondly, I think the LCR filter for the 2.5 is widely approved by cloners. I recall someone asking why ProAc didn't just include an LCR filter if it made a big difference, without getting a reply. Can someone comment on this? It will give confidence to future cloners knowing that that a basic 2.5 clone will sound amazing, and by adding the LCR, it sounds even better!
Proac reduce the peak through their use of a modified 8535 (unavailable to cloners). While I haven't personally compared any version of the clone side by side with the commercial model, I would be surprised if the latter would have as severe a problem with 2 KHz glare as the earliest clones (minus notch filter). Even so, Troels has now achieved a much more linear response than the commercial model and has completely eliminated the peak, so I would be surprised if his version didn't sound superior. As for whether the Proac original is worth its asking price, there has been much debate on this and I won't comment further.
My comments on the clone before the notch filter apply to both SS and valve amps of varying quality, from mid-fi to high end. I begged and borrowed quite a bit of equipment in the early stages, thinking it must be my gear causing the problem. It wasn't. The glare was there in varying degrees with every amp and source component I tried, and it stayed till I inserted the notch filter.
My comments on the clone before the notch filter apply to both SS and valve amps of varying quality, from mid-fi to high end. I begged and borrowed quite a bit of equipment in the early stages, thinking it must be my gear causing the problem. It wasn't. The glare was there in varying degrees with every amp and source component I tried, and it stayed till I inserted the notch filter.
Is this the XO to go for?
An externally hosted image should be here but it was not working when we last tested it.
Now I'm REALLY confused about which crossover I should build. I made one last night, and this morning, I called Meniscus Audio (these guys rock) and ordered the parts to build this one...
So I just called them back and ordered the parts to build the one in Jadde's pic.
I wish someone would make up their mind on which one is best.
An externally hosted image should be here but it was not working when we last tested it.
So I just called them back and ordered the parts to build the one in Jadde's pic.
I wish someone would make up their mind on which one is best.
Listening test: clone vs ProAc
Last june, I had an opportunity to listen to Jacq's clone and real ProAc 2.5. Jacq's clone had more bitumen felt and little Dacron damping. He told me that the brand of capacitor affect the midrange with some projecting it into the room. The version I listened to was brighter than the real ProAc which were darker in sound. French horn was a bit unatural, female voices were beatiful as was violin, guitar was better on the clone. I found the version of Jacq too bright to my taste. I liked the real ProAc.
I am building a pair now and will use Troels' last modifications and the 8.2 (I am not sure I remember the value) resistor to have as flat a response curve as possible.
Last june, I had an opportunity to listen to Jacq's clone and real ProAc 2.5. Jacq's clone had more bitumen felt and little Dacron damping. He told me that the brand of capacitor affect the midrange with some projecting it into the room. The version I listened to was brighter than the real ProAc which were darker in sound. French horn was a bit unatural, female voices were beatiful as was violin, guitar was better on the clone. I found the version of Jacq too bright to my taste. I liked the real ProAc.
I am building a pair now and will use Troels' last modifications and the 8.2 (I am not sure I remember the value) resistor to have as flat a response curve as possible.
so which caps are best???
been wanting to build these speakers myself but am kind of waiting to see just how the crossover values will settle out. also being a newbie to all of this i have been trying to get a good feel for just which cap's are best for this speaker and design.
what brands seem to be the most popular and best sounding for these drivers??? tried and test idea would be very very welcome.
thank you,
gary
been wanting to build these speakers myself but am kind of waiting to see just how the crossover values will settle out. also being a newbie to all of this i have been trying to get a good feel for just which cap's are best for this speaker and design.
what brands seem to be the most popular and best sounding for these drivers??? tried and test idea would be very very welcome.
thank you,
gary
On the question of the different crossovers, as Troels Gravesen says in his v5 PDF, a lot of clone builders want solutions, not options. Not all of us want to spend hours experimenting! Nevertheless, I think it's worthwhile trying the different crossover options (if you have the time, patience and money), as you may find one or the other works better in the context of your own system. But you may not want to bother with experiments, so . . .
If you want the nearest thing to the original, but with the advantage of the notch filter, then build the Jacq crossover with the addition of the notch filter as in the schematic Jadde shows, which was downloaded from http://www.geocities.com/diyproac25/crossover.htm (Al.M's Web site). (Note that there is some argument over whether to use 7.0 or 7.4uF in the woofer leg, and this schematic shows 7.0. On Al.M's site, the sections regarding Jacq's mods refer to 7.0uF, but others say 7.4 is correct. This is only about a 6 per cent increase, and to my ears is all but inaudible. Troels, however, does say the 7.4 value is critical.)
The schematic CptTripps' has included is Troels' latest tweaked version, and includes value changes to some basic components, as well as to the capacitor value in the notch filter. This is the xo I am using, and I do think it sounds better - but others may disagree. It certainly measures flatter.
It is worthwhile also experimenting with the value of the attenuating resistor on the tweeter. Try 5, 5.6, 6.8 and 8.2 ohms. There is much difference of opinion on which sounds best, and much will depend on your own system.
To understand the differences if you're confused about the various options, make sure you download Troels' PDF at http://members.chello.se/jpo/2_5_clone_measurements_v5.pdf, and read carefully what he has to say. I really think all cloners should do this. It includes the most comprehensive set of measurements and commentary I have seen published on the clone. (I just noticed that the link is being truncated here, so where it says cl..rements, type in clone_measurements in your browser.)
As far as capacitor quality goes, I used Solens, but the improvements over good-quality, off-the-shelf caps from Jaycar (an Australian electronics store) were not really all that great. I'm not really convinced this project justifies ultra-expensive xo components.
I shall be tied up till Monday or Tuesday of next week, so will not return to this thread till then.
If you want the nearest thing to the original, but with the advantage of the notch filter, then build the Jacq crossover with the addition of the notch filter as in the schematic Jadde shows, which was downloaded from http://www.geocities.com/diyproac25/crossover.htm (Al.M's Web site). (Note that there is some argument over whether to use 7.0 or 7.4uF in the woofer leg, and this schematic shows 7.0. On Al.M's site, the sections regarding Jacq's mods refer to 7.0uF, but others say 7.4 is correct. This is only about a 6 per cent increase, and to my ears is all but inaudible. Troels, however, does say the 7.4 value is critical.)
The schematic CptTripps' has included is Troels' latest tweaked version, and includes value changes to some basic components, as well as to the capacitor value in the notch filter. This is the xo I am using, and I do think it sounds better - but others may disagree. It certainly measures flatter.
It is worthwhile also experimenting with the value of the attenuating resistor on the tweeter. Try 5, 5.6, 6.8 and 8.2 ohms. There is much difference of opinion on which sounds best, and much will depend on your own system.
To understand the differences if you're confused about the various options, make sure you download Troels' PDF at http://members.chello.se/jpo/2_5_clone_measurements_v5.pdf, and read carefully what he has to say. I really think all cloners should do this. It includes the most comprehensive set of measurements and commentary I have seen published on the clone. (I just noticed that the link is being truncated here, so where it says cl..rements, type in clone_measurements in your browser.)
As far as capacitor quality goes, I used Solens, but the improvements over good-quality, off-the-shelf caps from Jaycar (an Australian electronics store) were not really all that great. I'm not really convinced this project justifies ultra-expensive xo components.
I shall be tied up till Monday or Tuesday of next week, so will not return to this thread till then.
<< an intolerable glare on vocals, strings and brass, accompanied by rather excessive sibilance >>……
<< a lack of lower midrange/upper bass energy >>……
<< tweeter's tendency to sibilance and the remaining problems in the midrange make this a very fussy speaker >>…….
<< much can be explained by the fact that both tweeter and mid-woofer are operating at the very extremes of their working ranges around the crossover point >>……..
<< The "nasties" I hear from the 8535 sound very much like cone break-up to me. (Incidentally, Troels has recently identified a 3 KHz peak resulting from resonance in the 8535's dust cap, and is experimenting with damping techniques.) >>……..
I would like to thank nadir, Al.M, Jacq, Troels and all others who have contributed to this project for all their hard work. I am about to build my clone after a hard search on the web. It is kind of discouraging after reading nadir’s love/hate relationship with the clones. As a matter of fact, I sort of like that. I do not believe in a perfect speaker. We all have to compromise and settle with “the fewer faults the better speakers”.
Here is my questions…..
Did the glare went away with Jacq’s mod and Troels’ LCR XO?
For a few of you build 2.5 clones and also own or owned real 2.5, are these problems of clones only or are they also the problems of the real ones? Or, are clones having more severe in degree on these problem than the real thing?, by how much? If I can cope with the price difference, I would go for it…….
I think the 4500 price tag on the real 2.5 should have something there to match. The special mod to the woofer cone for ProAc 2.5 must have the real magic potion………
I believe these are questions not only in my mind.
Thanks
Chengs
<< a lack of lower midrange/upper bass energy >>……
<< tweeter's tendency to sibilance and the remaining problems in the midrange make this a very fussy speaker >>…….
<< much can be explained by the fact that both tweeter and mid-woofer are operating at the very extremes of their working ranges around the crossover point >>……..
<< The "nasties" I hear from the 8535 sound very much like cone break-up to me. (Incidentally, Troels has recently identified a 3 KHz peak resulting from resonance in the 8535's dust cap, and is experimenting with damping techniques.) >>……..
I would like to thank nadir, Al.M, Jacq, Troels and all others who have contributed to this project for all their hard work. I am about to build my clone after a hard search on the web. It is kind of discouraging after reading nadir’s love/hate relationship with the clones. As a matter of fact, I sort of like that. I do not believe in a perfect speaker. We all have to compromise and settle with “the fewer faults the better speakers”.
Here is my questions…..
Did the glare went away with Jacq’s mod and Troels’ LCR XO?
For a few of you build 2.5 clones and also own or owned real 2.5, are these problems of clones only or are they also the problems of the real ones? Or, are clones having more severe in degree on these problem than the real thing?, by how much? If I can cope with the price difference, I would go for it…….
I think the 4500 price tag on the real 2.5 should have something there to match. The special mod to the woofer cone for ProAc 2.5 must have the real magic potion………
I believe these are questions not only in my mind.
Thanks
Chengs
I built the original crossover, and I'll be building the one I pictured above today. That way I can "A-B" them and see which I like better. In all honesty, I LOVE the experimenting part, but I have almost NO electrical experience/understanding. I always try to understand it, but my ADD kicks in about 30sec after I start reading and I'm off to something else. =)
I used all Solon caps, and to build the crossovers I spent about $120 to build both versioins. I figure I could break the other down after I pic one and seal it in there. My next project is a ProAc Responce 2s clone for the office. So I'm starting to build crossovers for that too. (I'll be starting that thread later today.)
I used all Solon caps, and to build the crossovers I spent about $120 to build both versioins. I figure I could break the other down after I pic one and seal it in there. My next project is a ProAc Responce 2s clone for the office. So I'm starting to build crossovers for that too. (I'll be starting that thread later today.)
Just to reiterate:
With the very original Chinese crossover (which you'll find on Al.M's site), there was a very marked peak around 2 KHz. Jacq's mods reduced this peak to some extent, but it was still there and led to a degree of "glare" on vocals, strings and brass in particular - in the opinion of a number of us, anyway.
The addition of Troels Gravesen's notch filter (LCR) to the Jacq-modded xo (also on Al.M's site or in Troels' PDF) flattens out the peak, and the glare disappears . . . gone . . . finito. Troels' own later version of the xo also includes a notch filter and produces an even flatter response in the crossover region. Once again, there is no problem with glare.
While it is arguable that the 2.5 clone is still not perfect (no speaker is), the removal of the glare was a major breakthrough and IMO we all owe Troels a huge debt of gratitude for his work.
Glad to see there are more than a few cloners out there who are happy to experiment. The 2.5 clone is very much a work in progress and I have a sneaky feeling we are going to hear more from folks like Troels.
With the very original Chinese crossover (which you'll find on Al.M's site), there was a very marked peak around 2 KHz. Jacq's mods reduced this peak to some extent, but it was still there and led to a degree of "glare" on vocals, strings and brass in particular - in the opinion of a number of us, anyway.
The addition of Troels Gravesen's notch filter (LCR) to the Jacq-modded xo (also on Al.M's site or in Troels' PDF) flattens out the peak, and the glare disappears . . . gone . . . finito. Troels' own later version of the xo also includes a notch filter and produces an even flatter response in the crossover region. Once again, there is no problem with glare.
While it is arguable that the 2.5 clone is still not perfect (no speaker is), the removal of the glare was a major breakthrough and IMO we all owe Troels a huge debt of gratitude for his work.
Glad to see there are more than a few cloners out there who are happy to experiment. The 2.5 clone is very much a work in progress and I have a sneaky feeling we are going to hear more from folks like Troels.
I just finished reading all the above comments on the proac clones. I finished mine 6 weeks ago and ran them 100 hours in the first week and have listened to them every day since. I'm using audible illusions 3a and bryston 3bsst. Everything stated above about the sound closely resembles what I hear but I find the midrange will keep me from wanting to have them as a main speaker(I can't imagine the originals sounding this way).
I owned a pair of the original response 2 loudspeaker for 3 years but sold them after a break-up. The midrange purity and dynamics of the 2's is unbelievable. I understood that all proac's have that seemless, open and natural midrange(the 1sc does).
None of this was to complain. I enjoyed the project(the veenering worked out amazingly) and will hope that future changes may fix the problem and will gladly experiment with mine. Thank's, jacq and troels and eveyone involved.
I will now look for new/used speakers. Anyone want to sell there response 2's.
Joel
I owned a pair of the original response 2 loudspeaker for 3 years but sold them after a break-up. The midrange purity and dynamics of the 2's is unbelievable. I understood that all proac's have that seemless, open and natural midrange(the 1sc does).
None of this was to complain. I enjoyed the project(the veenering worked out amazingly) and will hope that future changes may fix the problem and will gladly experiment with mine. Thank's, jacq and troels and eveyone involved.
I will now look for new/used speakers. Anyone want to sell there response 2's.
Joel
I finally got mine together last night, and I've got to tell you...I'm REAL happy with the standard crossover design. I've got the parts to add the notch filter later if I want. But I'm not going to bother listening to the "V3" crossover.
I've got all the parts to build the V3 crossovers, if anyone is interested, I'll be happy to sell them.
-Doug
I've got all the parts to build the V3 crossovers, if anyone is interested, I'll be happy to sell them.
-Doug
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