pete_mac
26-04-2012, 01:11
Howdy,
I hope this doesn't strike a nerve due to the 'clone' nature of these speakers, but I thought I'd share some info anyway.
I bought a pair of these ProAc 1S clones in early April. The feature genuine SEAS and Scan-Speak drivers in a nicely made and very solid cabinet, and are quite the bargain at around $AUD580 landed.
The original crossovers are based on a hybrid of the 1S and 1SC crossovers, with a few alterations here and there by the Chinese manufacturers. They seemed to sound OK at first listen but were a bit veiled and thick, even after about 200 hours in my 'burn-in rig'.
The burn-in rig lives in my garage and consists of an old Marantz amp switched to mono, with one speaker wired out of phase and both speakers facing each other to reduce the volume level, then many many heavy blankets on top.
I figured that improved crossover components would help, and returning to the original 1S crossover (or Troels Gravesen's slightly tweaked crossover design as per his website) would be the way to go, especially as these are not the same 'special' drivers as found in the 1SC.
http://i535.photobucket.com/albums/ee359/petemacozfoz/1sc1.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/1sc2.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/1sc3.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/1scvslenehan2.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/1Sclonedrivers.jpg
The new crossover components - Jantzen inductors, Jantzen MOX resistors and some AXON caps. The AXON caps in the tweeter circuit were temporary untill I could secure some Clarity Cap ESAs for this part of the crossover.
http://i535.photobucket.com/albums/ee359/petemacozfoz/jantzen1.jpg
The original crossovers - electrolytic and polyester capacitors, and fairly small-gauge inductors:
http://i535.photobucket.com/albums/ee359/petemacozfoz/cloneoriginalcrossover.jpg
Inductor comparison:
http://i535.photobucket.com/albums/ee359/petemacozfoz/cloneinductorsoldvsnew.jpg
Crossovers before an after:
http://i535.photobucket.com/albums/ee359/petemacozfoz/clonecrossoversoldvsnew.jpg
Two completed crossovers, including new wiring for the woofer (some Synergistic Research copper/silver alloy wire that I had lying around):
http://i535.photobucket.com/albums/ee359/petemacozfoz/clonecrossoverstwonewcompleted.jpg
After fitting the new components the sound was improved straight away - more open, more detail, tighter bass. The speakers were placed back into the burn-in rig for another 200 hours or so.
The last piece of the puzzle is the aforementioned Clarity Cap ESAs in the tweeter circuit. They are MUCH larger than the smaller 250V AXONs:
http://i535.photobucket.com/albums/ee359/petemacozfoz/clarity2.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/clarity1.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/clarity4.jpg
I'm about to go away for a short holiday so I'll again put the speakers back into the burn-in rig, and will have a good listen to them upon my return. By that stage the drivers will have around 600 hours on them (well and truly loosened up!) and the capacitors and inductors will have between 200-400 hours on them.
One point to note is that the oringal ProAcs had a 5.6ohm resistor in the tweeter circuit, whereas the clones came with a 6.8ohm and Troels Gravesen recommends an 8.2ohm resistor. I found the 8.2ohm to be a little dark when originally fitted with the AXON caps, so I fitted a 6.8ohm instead. I'm experimenting with 0.33ohm and 0.56ohm resistors between the binding posts to slightly attenuate the tweeter, and so far I'm quite liking the 0.56 ohm. I'll muck around further upon my return from holidays.
Watch this space for further listening impressions.
I hope this doesn't strike a nerve due to the 'clone' nature of these speakers, but I thought I'd share some info anyway.
I bought a pair of these ProAc 1S clones in early April. The feature genuine SEAS and Scan-Speak drivers in a nicely made and very solid cabinet, and are quite the bargain at around $AUD580 landed.
The original crossovers are based on a hybrid of the 1S and 1SC crossovers, with a few alterations here and there by the Chinese manufacturers. They seemed to sound OK at first listen but were a bit veiled and thick, even after about 200 hours in my 'burn-in rig'.
The burn-in rig lives in my garage and consists of an old Marantz amp switched to mono, with one speaker wired out of phase and both speakers facing each other to reduce the volume level, then many many heavy blankets on top.
I figured that improved crossover components would help, and returning to the original 1S crossover (or Troels Gravesen's slightly tweaked crossover design as per his website) would be the way to go, especially as these are not the same 'special' drivers as found in the 1SC.
http://i535.photobucket.com/albums/ee359/petemacozfoz/1sc1.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/1sc2.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/1sc3.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/1scvslenehan2.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/1Sclonedrivers.jpg
The new crossover components - Jantzen inductors, Jantzen MOX resistors and some AXON caps. The AXON caps in the tweeter circuit were temporary untill I could secure some Clarity Cap ESAs for this part of the crossover.
http://i535.photobucket.com/albums/ee359/petemacozfoz/jantzen1.jpg
The original crossovers - electrolytic and polyester capacitors, and fairly small-gauge inductors:
http://i535.photobucket.com/albums/ee359/petemacozfoz/cloneoriginalcrossover.jpg
Inductor comparison:
http://i535.photobucket.com/albums/ee359/petemacozfoz/cloneinductorsoldvsnew.jpg
Crossovers before an after:
http://i535.photobucket.com/albums/ee359/petemacozfoz/clonecrossoversoldvsnew.jpg
Two completed crossovers, including new wiring for the woofer (some Synergistic Research copper/silver alloy wire that I had lying around):
http://i535.photobucket.com/albums/ee359/petemacozfoz/clonecrossoverstwonewcompleted.jpg
After fitting the new components the sound was improved straight away - more open, more detail, tighter bass. The speakers were placed back into the burn-in rig for another 200 hours or so.
The last piece of the puzzle is the aforementioned Clarity Cap ESAs in the tweeter circuit. They are MUCH larger than the smaller 250V AXONs:
http://i535.photobucket.com/albums/ee359/petemacozfoz/clarity2.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/clarity1.jpg
http://i535.photobucket.com/albums/ee359/petemacozfoz/clarity4.jpg
I'm about to go away for a short holiday so I'll again put the speakers back into the burn-in rig, and will have a good listen to them upon my return. By that stage the drivers will have around 600 hours on them (well and truly loosened up!) and the capacitors and inductors will have between 200-400 hours on them.
One point to note is that the oringal ProAcs had a 5.6ohm resistor in the tweeter circuit, whereas the clones came with a 6.8ohm and Troels Gravesen recommends an 8.2ohm resistor. I found the 8.2ohm to be a little dark when originally fitted with the AXON caps, so I fitted a 6.8ohm instead. I'm experimenting with 0.33ohm and 0.56ohm resistors between the binding posts to slightly attenuate the tweeter, and so far I'm quite liking the 0.56 ohm. I'll muck around further upon my return from holidays.
Watch this space for further listening impressions.