They did not fail!...I still use them today...and will keep until I built something better (hasn't happened yet). They have their faults like most speakers. Love the SS 8535 midrange, the percussion pop, 3D soundstage is best I have in the house. The main fault I perceive is the somewhat loose bass, definitely not the tightest.
Apparently the woofer response peak rising at 2-2.5k was the problem and it was not addressed very well in the crossover (based on plots and e-mail with D. Murphy ca. 2005). However i am convinced in my case it is not the problem. I bought drivers directly from Europe...there were rumors they had changed some in production design ??. So maybe I got lucky and got a pair that are well behave (sorry I do not have mic to measureand confirm).
Furthermore, I remember when I built mine, I used large copper foil inductors and good Caps (Sonicap) I also remember reversing polarity on the Caps and the midrange clarity changed for the better. As for the sibilance I ended using two resistor in parallel with tweeter for less current/inductance and it helped.
Apparently the woofer response peak rising at 2-2.5k was the problem and it was not addressed very well in the crossover (based on plots and e-mail with D. Murphy ca. 2005). However i am convinced in my case it is not the problem. I bought drivers directly from Europe...there were rumors they had changed some in production design ??. So maybe I got lucky and got a pair that are well behave (sorry I do not have mic to measureand confirm).
Furthermore, I remember when I built mine, I used large copper foil inductors and good Caps (Sonicap) I also remember reversing polarity on the Caps and the midrange clarity changed for the better. As for the sibilance I ended using two resistor in parallel with tweeter for less current/inductance and it helped.
I have the R2.5 clones in my room now, I'm holding them for a friend.
The integration of the drivers is very good, exposing recorded detail that supports a good soundstage, but my 2way speakers with physical alignment of acoustic centers, spherical cabinet shapes and felt surfaces, are much better at unmasking details, Hence, even better imaging.
Looking at bass primarily, here is R2.5 clone compared to 2 other speakers - one ported and one sealed. Box/port sims and in room FR.
The integration of the drivers is very good, exposing recorded detail that supports a good soundstage, but my 2way speakers with physical alignment of acoustic centers, spherical cabinet shapes and felt surfaces, are much better at unmasking details, Hence, even better imaging.
Looking at bass primarily, here is R2.5 clone compared to 2 other speakers - one ported and one sealed. Box/port sims and in room FR.
Attachments
Thanks, Boswald.
I just had a quick look at REW and see I need a calibrated microphone. I don't have one, but do have what might be the next best thing - an Audyssey microphone, which are all designed to be similar to one another, and someone else's calibration curve from the internet. I won't cross link to another forum here - it seems bad manners.
It'll give me something to play with this afternoon when the family goes out
[Following up for politeness.]
So, I played around a bit. In all reality, I can buy used 2.5's on eBay for less money and less work than I can make some, and there's a real chance they'll be a better match visually and audibly for my existing 2.5's than something I make myself. Until a matching pair appears, I'm going to make surround speakers from Dayton Audio exciters. Will try onto sheetrock, the window, and/or acrylic. May need to add a tweeter.
Old thread but still very good and relevant even now, so I thought I'd join in. Cloning speakers I think is a possibility but for your average DIY'er I think maybe not. Although you will be able to build some speakers but getting it near ProAcs standards I think not from where I see it now anyway.
I would love to hear the best clone and a genuine 2.5 side by side but its probably never going to happen. And its not about building better its about building exact I find interesting.
The speakers build itself we can replicate fairly straight forward even if its not perfect it'll do, but as has been said here creating that sound signature is another matter. ProAc are world known and respected speakers. They are used in high end domestic and studio use worldwide. To me they have an aspect of realism in the sound, tonal accuracy and realistic instrument and vocal timbre which most speakers just don't have. In general they use a wide range of general off the shelf and available 'good' drive units such as the like of Scan Speak, yet if I copied what they did I don't think I would get a ProAc sounding speaker.
Stewart Tyler (ProAc's father) has told me that he puts more effort into the crossover than any other part of the speaker, spending as much as 2 years just developing that alone on some designs.
I don't like what these speakers cost so I try a DIY alternatives but it usually falls short. Do you really think me learning something like Xsim will get me to build a perfect copy?
I would love to hear the best clone and a genuine 2.5 side by side but its probably never going to happen. And its not about building better its about building exact I find interesting.
The speakers build itself we can replicate fairly straight forward even if its not perfect it'll do, but as has been said here creating that sound signature is another matter. ProAc are world known and respected speakers. They are used in high end domestic and studio use worldwide. To me they have an aspect of realism in the sound, tonal accuracy and realistic instrument and vocal timbre which most speakers just don't have. In general they use a wide range of general off the shelf and available 'good' drive units such as the like of Scan Speak, yet if I copied what they did I don't think I would get a ProAc sounding speaker.
Stewart Tyler (ProAc's father) has told me that he puts more effort into the crossover than any other part of the speaker, spending as much as 2 years just developing that alone on some designs.
I don't like what these speakers cost so I try a DIY alternatives but it usually falls short. Do you really think me learning something like Xsim will get me to build a perfect copy?
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Well, you don't actually need to learn how to use Xsim or any other design software for a 2.5 clone since all of the crossover details are available online. Same goes for the boxes, even down to the damping material & internal wire. There is no such thing as an absolutely 'perfect' copy as you may not be using exactly the same caps, coils etc. but you can certainly use the same general type & values thereof. The Scan drivers were produced for ProAc but we already know the similarity in baseline response and the fact that some have A/B compared & found them more or less identical, so those changes may have been down to something as simple as a different connector or label. Drivers can change a little over the years, but you should end up with something very close.
Funny, I was thinking just the other day about the possible marketing ideas of Proac. At the time R2.5 was released was there a trend for tall slim 2way speakers with with heavy colored bass? Was it different and unusual to have a speaker with 3/4 dome tweeter to create a buss with the ads and reviews? Was it cool to offset the tweeter to the side and space it a little further from the woofer? All of this, a little sexy maybe? Accurate reproduction, Meaningless!
Edit: 2.5 is rear ported and is a big part of the bass color - room interaction, etc!
Edit: 2.5 is rear ported and is a big part of the bass color - room interaction, etc!
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Funny, I was thinking just the other day about the possible marketing ideas of Proac. At the time R2.5 was released was there a trend for tall slim 2way speakers with with heavy colored bass? Was it different and unusual to have a speaker with 3/4 dome tweeter to create a buss with the ads and reviews? Was it cool to offset the tweeter to the side and space it a little further from the woofer? All of this, a little sexy maybe? Accurate reproduction, Meaningless!
Edit: 2.5 is rear ported and is a big part of the bass color - room interaction, etc!
Accurate reproduction you say. Perhaps they don't measure well I don't even know but to me ProAc are one of the most realistic sounding speakers one can buy imo. If there are few speakers that can capture the sound of the event I would put ProAc near the top in my long experience of being an audiophile. And the 2.5 did it in a neat package while being relatively full scale with it I thought.
Well... for you at least !
My own experience as an ex Proac owner is not that. I still think for the more demanding of us their two way are limited as their ribbon models. Their 3 ways Pro are in an other league though
It's not the 2 ways are bad, clearly they ar not, but they are too straight spl by choice and not acurate to my ears because of that : it's a mrketing choice many brands made in the 80s'. Luckilly things evolved.
My own experience as an ex Proac owner is not that. I still think for the more demanding of us their two way are limited as their ribbon models. Their 3 ways Pro are in an other league though
It's not the 2 ways are bad, clearly they ar not, but they are too straight spl by choice and not acurate to my ears because of that : it's a mrketing choice many brands made in the 80s'. Luckilly things evolved.
Going through the questions in order:
There are two separate matters here. Firstly, yes, slim column speakers became increasingly popular from the 1980s, especially with UK manufacturers, so the 2.5 was and remains perfectly normal in this regard. As far as bass alignment goes, the 2.5 basically had a flat cabinet alignment, but the general response trend was gently lifted at each frequency extreme so it could be used effectively in larger spaces and away from boundaries. This is quite common for smaller speakers like the 2.5 since a flat or slightly down-tilting response can sound slightly lost if used in large rooms for reasons sufficiently well-known not to need any explanation here.
Not as far as I know. 3/4in dome tweeters aren't particularly unusual, then or now, and to use the contemporary Stereophile review as an example, the midbass seemed to get more attention than the tweeter.
Just a common-sense engineering solution to help reduce on-axis diffraction effects. Since ProAc do not use chamfers or roundovers on their baffle edges, a lateral offset can be especially useful in these cases, the degree being determined by measurement.
Quickly referring to a saved plan of the box, it appears to have been 12mm between the basket edges. A bit more than I'd use, but not particularly large. They could probably have packed it a few mm closer but these aren't large differences, and a slightly more conservative spacing may have allowed a reduced production QC failure rate. It only takes a glue-pocket or similar in the wrong place to cause problems when you're cutting two large holes in close proximity.
Well, the enclosure alignment dominates rather than the position of the vent on the front or rear baffle as such. With the wavelengths in question, it will interact with boundaries whereever the vent is placed. A rear vent may have a slightly different coupling, but in the 2.5 it's positioned relatively high up, which tends to reduce that effect compared to a duct placed closer to the floor. As JA noted in his Stereophile measurements, an advantage is that the 1/2 wave self-resonance of the duct will be rendered largely inaudible with the rear vent position. The overall response trend of the 2.5 looks to be quite well-suited to use in larger spaces, or for those who like a greater bias toward the frequency extremes in smaller spaces. It's not above criticism, and it won't suit all requirements, but I can't see much in the form-factor, cabinet alignment, driver spacing & offset to draw much objection from an engineering POV. Most critiques tend to centre around the crossover & driver choices. The former is fair comment; we all prioritise different things. The latter is fair enough too but that also means anything resulting is an inherently different speaker.
There are two separate matters here. Firstly, yes, slim column speakers became increasingly popular from the 1980s, especially with UK manufacturers, so the 2.5 was and remains perfectly normal in this regard. As far as bass alignment goes, the 2.5 basically had a flat cabinet alignment, but the general response trend was gently lifted at each frequency extreme so it could be used effectively in larger spaces and away from boundaries. This is quite common for smaller speakers like the 2.5 since a flat or slightly down-tilting response can sound slightly lost if used in large rooms for reasons sufficiently well-known not to need any explanation here.
Not as far as I know. 3/4in dome tweeters aren't particularly unusual, then or now, and to use the contemporary Stereophile review as an example, the midbass seemed to get more attention than the tweeter.
Just a common-sense engineering solution to help reduce on-axis diffraction effects. Since ProAc do not use chamfers or roundovers on their baffle edges, a lateral offset can be especially useful in these cases, the degree being determined by measurement.
Quickly referring to a saved plan of the box, it appears to have been 12mm between the basket edges. A bit more than I'd use, but not particularly large. They could probably have packed it a few mm closer but these aren't large differences, and a slightly more conservative spacing may have allowed a reduced production QC failure rate. It only takes a glue-pocket or similar in the wrong place to cause problems when you're cutting two large holes in close proximity.
Well, the enclosure alignment dominates rather than the position of the vent on the front or rear baffle as such. With the wavelengths in question, it will interact with boundaries whereever the vent is placed. A rear vent may have a slightly different coupling, but in the 2.5 it's positioned relatively high up, which tends to reduce that effect compared to a duct placed closer to the floor. As JA noted in his Stereophile measurements, an advantage is that the 1/2 wave self-resonance of the duct will be rendered largely inaudible with the rear vent position. The overall response trend of the 2.5 looks to be quite well-suited to use in larger spaces, or for those who like a greater bias toward the frequency extremes in smaller spaces. It's not above criticism, and it won't suit all requirements, but I can't see much in the form-factor, cabinet alignment, driver spacing & offset to draw much objection from an engineering POV. Most critiques tend to centre around the crossover & driver choices. The former is fair comment; we all prioritise different things. The latter is fair enough too but that also means anything resulting is an inherently different speaker.
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Its simple to accomplish with measuring equipment, crossover modeling and lot of spare time to play
- Reasonably flat through the midrange, precise phase tracking smooth transition to off-axis and bingo, the sound of the event is captured.. With 2.5 the bass from the event is not captured very well unless moved out from the wall by a large amount- See post 23, where I measured 2.5 in room, appears much like Stereophile's measurement.
If you learn to design and build speakers from scratch using measuring equipment, a crossover simulator, and given enough time, you will produce better sounding speakers than R2.5. There will be no interest in cloning them..
The last one. It works in electrical domain with single loaded auxiliary response which is typically totally inadequate for designing crossover of loudspeaker.
I was unable to find Troels' excellent paper on his site so downloaded it from Wayback (2013):
Had to split it into PART 1 and 2 due to forum file size limits.
On page 19 he gives a summary (probably up to that point):
Version 1 is a clone of the original (not sure if this is a best guess or traced out from a real one)
Version 2 There is a noted 2 KHz bump, this adds an LCR to tame the bump.
Version 3 Is a crossover mod for an even smoother response than Version 2.
There are more versions that include modding the drivers and using a different tweeter,
read on in the document to learn about them.
Had to split it into PART 1 and 2 due to forum file size limits.
On page 19 he gives a summary (probably up to that point):
Version 1 is a clone of the original (not sure if this is a best guess or traced out from a real one)
Version 2 There is a noted 2 KHz bump, this adds an LCR to tame the bump.
Version 3 Is a crossover mod for an even smoother response than Version 2.
There are more versions that include modding the drivers and using a different tweeter,
read on in the document to learn about them.
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Well... for you at least !
My own experience as an ex Proac owner is not that. I still think for the more demanding of us their two way are limited as their ribbon models. Their 3 ways Pro are in an other league though
It's not the 2 ways are bad, clearly they ar not, but they are too straight spl by choice and not acurate to my ears because of that : it's a mrketing choice many brands made in the 80s'. Luckilly things evolved.
Well as far as speakers go yes it is to me. I've had speakers of all shapes and sizes and they all pretty much sound like speakers, even some which some others say sound more like real music than hifi your Shainians et al. And I've spent considerable time with some of the most exotic at shows your big Focal Grand Utopias, Wilson Benesh, horns whatever.
I've played in live bands myself as a musician also and to me there is a tonality to ProAc like live sound but still very much about the music, drawn into it and enjoyment rather than hi-fi and overanalysing but still very detailed. They are some of the best I've ever heard at any price I've heard.
Cant say I've owned the 2.5s but heard plenty. I have owned 1.5 though and 1sc and a number of other models including fancy signature tablets and lots of others. They all seem to have a fairly consistent sound that I described. I even used to play my guitar at home along with my 1.5s the reproduction of drums at higher levels and vocals among other things it all just felt very lifelike.
Now I like this tweeter a lot, its one of my favourites that was used in ProAcs models. To me it had a very metal sounding edge to it, like on cymbal crashed steel guitar strings yet had none of the sometimes fatigue that is gotten from metal dome designs. Yet I really like metal dome tweeters when used well as well. However, why do they cost so much? These Scan Speakes are still in popular production and are around £70 each here in the UK.
Its simple to accomplish with measuring equipment, crossover modeling and lot of spare time to play
Here is that funny word again
'better', better will always be a totally subjective thing. But the idea anyway is replicate, I like the 2.5s just an exact clone would be very nice, if possible. Although I think the secret sauce is in the crossover as far as I can see it with ProAc designs. ok so here's another proposition. Can you model a crossover and sound characteristics more easily with an active crossover like a dayton audio, Wondom or miniDSP whatever and by using good measurement equipment like a Dayton Audio Omnimic V2?
I don't think I would be able to quickly master any art of working with coils and resistors to ProAcs standards to create a clone. However working with real time adjustable variables in software would be 'a lot' easier for me.
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More easily compared to what? On-line adjustment with active DSP device? That would be quite random, slow and more subjective method to produce anything universal which would work decently in different rooms and locations.
Anyway, gear should be able to measure timing so OmniMic v2 is not always good enough for capturing measurement data for crossover simulation with acoustical data in two planes (or full space) which is needed to design XO with directivity information. In addition, XSim supports axial only so designs with it are not plausible.
I wasn't talking about cloning. Personally I don't see enough reasons to clone anything if valid tools are available and knowledge about speakers+acoustics so my messages are kinda off topic.
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Excellent point made here. As there is no relative scale of audio quality better is exactly that, whatever you want it to be. If there was a relative scale in audio lots may aspire to it but it is all mainly subjective experience hence the infinite number of different favourites people have.
Yes the crossover is a tricky one to master.
I think making something that sounds better then to you may be an easier task than a complete exact clone of the 2.5 ProAc, unless you were involved in the design obviously or worked in the production or something. And I know Stewart Tyler at ProAc spends more time on his crossovers than any other component, sometimes up to 2 years adjusting he told me. I think the best we can expect is something that sounds similar if cloned. Although the Chinese seem to becoming increasingly better and better at copying things but not that others cant do it equally as well either.
Its an interesting thing trying to make exact replicas of things. I once watch some American factory / science lab (IIRC) try and make an exact replica of a classic Eric Clapton guitar 'Blackie', it was on youtube if anyone's interested. They took it apart piece by piece and analysed it and precision made it so everything was exact. I forget how that turned out now but most of the time we have a pretty easy time of spotting something slightly different, and to me lots of the clones I have seen of things particularly speakers are not quite as good 'to me' as if you would have bought a legit one from the manufacturer.
Compared to making a hand made passive crossover. With an active you can adjust more easily in real time and possibly model what another passive crossover may be doing to get a final end result that's all I'm saying. Just as guitar amp simulators modellers do digitally. They reproduce exact tones of the sometimes boutique analogue equipment to a high degree of accuracy. It used to be fairly crude in the earlier days but would get you some sort of near sound. However, modern technology has even taken that further and it is hard to distinguish the two all analogue components against purely digital generated signal.
Anyway what I am trying to say is can you mimic a crossover by adjusting manually an active one and using microphones to capture the frequency responses and timing etc to match the characteristics of a hard wired passive crossover?