Hello Folks.
Intro:
These are the Abacus C-Box 3 speakers, sold in the EU, usually for 990 Euros (1105 USD / 1493 CAD) for a pair: https://www.abacus-electronics.de/produkte/aktivlautsprecher/c-box/c-box3.html. Abacus C-Box 3 speakers are 4" active speakers (they have active crossovers) with ring tweeters and 25W RMS amplification per channel. They use proprietary "DOLIFET" amplifiers with active crossover and with compensation for electromotive force. Speaker cabinets are sealed (acoustic suspension), the only input is one RCA Line level per box (they can be used as passive speakers with input adapters) and they are completely analog. They also come in slightly larger version (C-Box 4 with identical amplification module and 5" mid-woofer) and there is also matching active subwoofer (C-Bass 10). Abacus C Boxes are originally developed as high-end hi-fi desktop speakers, but they are also used in some professional studios for mixing and mastering. All models are developed and produced in-house by Abacus Electronics UG in Nordenham Germany. The company was founded in 1983. by Mr. Karl-Heiz Sonder and today is run by him and his son, Mr. Hanno Sonder. Today the company, besides active speakers, produces a line of preamps and amps, as well as couple of streaming devices. I have had speakers for more than 3 months and I have been listening to them almost daily with a variety of music, mostly electronic and classical, some jazz and pop/rock and a bit of metal (SACDs, CDs, Blu-ray DVDs, lossy streaming).
User experiences:
-Speakers are quite small. They are also not very heavy, but thanks to the small size and good build, they feel sturdy. When knocked on, housing does not resonate noticeably. Power rocker has good feel to it and two rotating pots feel plasticky (Volume and Bass EQ), but they turn smoothly. The box is completely sealed (acoustic suspension). They are not vinyl-wrapped, but have structural paint on, wich looks and feels a bit utilitarian but high-quality. LED is purple, moderately bright, but offers no info about clipping. Speakers were delivered with two-pin power cables and one wall socket adapter (1 in, 2 out). They came neatly packed in a carefully measured box, wich should be kept for safe transport of the speakers (ring tweeters stick out a few mm out of the speaker cabinets).
-I have the boxes positioned on Stagg budget stands and isolation foam, toed in, distanced about 25cm from the front wall. Distance between the speakers is slightly less than 2m, and listening distance is slightly less than 2.5m. Sidewalls and windows are more than 2m away on both sides. In this setting, speakers sound natural, free of excessive room coloration and the sound stage does not extend much beyond them. Imaging is fairly precise and there is also some hint of third dimension (big screen TV between them works against holography). I had no trouble optimising their placement with small changes, but they do sound horizontally directional though, so no "room filing" sound from these. On the other hand, having ears a bit above or below tweeter level, does not change my sonic experience much.
-They do not get very loud (at least not without bass distortion), so listening above roughly 80dB, even in near to mid-field, is simply not realistic. When the bass EQ is turned on max, which is the default setting for flat response, testing with sine wave generator gives me sensation of usable bass down to about 41-42Hz. Maximum low extension seems to be around 36-37Hz. If one wants to listen at about 75dB to 80dB, it is possible to sacrifice bass extension for SPL by turning the bass EQ down to the minimum. In order to avoid distortion, main volume control also should not to go past half position, unless there is a preamp volume control. Since I have been using them with a preamp, they do not seem to be fussy about being fed with low vs high level signal and having their own volume control higher vs lower.
-Despite a good bass extension for their size, they do not sound like large speakers. They sound like 4" speakers, yet ones supported with a small, extremely well integrated, 5 or 6 inch subwoofer (provided listening levels remain bellow 80dB). It sounds almost as if additional bass drivers are mounted on the back of the speaker cabinets. The bass is fairly deep, if not strong, it is very well defined (fast and distortion-free) and amazingly rich in texture. I can tell a difference between bass guitar and double bass as a difference between night and day. Some bass punch can be heard, certainly not felt, but the best thing about bass is that it does not smear the lower mids (or any other frequency range). Sound of this speaker is complete opposite of being "boomy".
-Mids sound pretty much more natural and correct than any small speaker I have ever heard (Genelec and Neuman included). Female voices sound better than male voices, since the mid-woofer is small. Dynamics of small scale are good, response is very fast, so transients sound very good at lower listening levels. Sound, in general, is open, direct, and the separation of instruments within mid-frequencies is especially good. Smaller instruments simply sound correct, yet pianos sound small, just like symphonic music does not reach much of it's scale, but that is the way it must be with very small speakers. With some distorted and overdriven rock/metal guitars, they do sometimes sound a bit "shouty", but not overly unpleasant.
-Highs are not extremely extended, but what is there is very informative and pleasant sounding, "airy" and nicely rounded (there is no piercing or sibilance). I do not remember I have ever heard subjectively better balance between high-end resolution and absence of listening fatiguing. Even though ring tweeters looks a bit funny in theirs shallow (kind of) waveguides, highs sound as continuous part of the whole frequency spectrum. Cymbals sound like metal discs struck with wooden sticks, not like small air compressors letting out pressurised air, and sure not like someone is rubbing quickly something agains metal. Another good thing about top frequencies is that they are extremely clean, there is not a trace of any hiss, no matter how close I put my ear to the tweeter.
Summary:
It is no surprise that these tiny speakers cannot handle big dynamics good, but fine dynamics are very good. Accordingly, they do not make a great listening tool for big scale orchestral music or epic rock/prog/metal works. Acoustic and vocal music sounds decent enough. What is a bit surprising is that they seem to sound great when reproducing well produced bassy mixture of electronic and non-electronic instruments or progressive electronica (as long as the mix is not extremely busy). Jazz recordings tend to sound particularly exciting, especially if recorded live. Things sound rhythmical and in correct phase, there is no hiss, no hum, and as long the volume is in check, there are no noticeable distortions. Staging and imaging are good and even holographic. Frequencies are reproduced naturally and even smaller details in music are present. Still, beware, these small Abacus boxes are not very forgiving of bad sources. They do not go out of their way to make music sound horrible (or "clinically" analytical), but they also do not give music "make-up" and they pick up electrical noises easily. So, give them decent cables and decent sources with decently produced music and the sound becomes enough "musical" and simply fun and enjoyable that you can forget that you are listening to a pair of 4" two-way active speakers with only 25W per channel at low(ish) living-room levels. They are not cheap, they are spartan, but they are well built and they sound great. If I would to describe Abacus C-Box 3 in 3 words, they would be (in no particular order): Engineered, Natural, Precise. Would I buy them again: Yes. Would I recommend them? Well, if you are into quiet(er) listening of electronica and jazz and do not mind the lack of connectivity, or you simply want "end-game" small desktop speakers, Abacus C-Box 3 speakers are probably the way to go.
Paired equipment: Pioneer DV-575A DVD/SACD Player; Abacus Linetreiber 2020 Variabel Preamp; Acoustic Tuning Cables.
Additional equipment: Sony PS4 Game Console; FiiO BR13 Bluetooth Receiver/DAC.
Pictures:
Cheers.
Intro:
These are the Abacus C-Box 3 speakers, sold in the EU, usually for 990 Euros (1105 USD / 1493 CAD) for a pair: https://www.abacus-electronics.de/produkte/aktivlautsprecher/c-box/c-box3.html. Abacus C-Box 3 speakers are 4" active speakers (they have active crossovers) with ring tweeters and 25W RMS amplification per channel. They use proprietary "DOLIFET" amplifiers with active crossover and with compensation for electromotive force. Speaker cabinets are sealed (acoustic suspension), the only input is one RCA Line level per box (they can be used as passive speakers with input adapters) and they are completely analog. They also come in slightly larger version (C-Box 4 with identical amplification module and 5" mid-woofer) and there is also matching active subwoofer (C-Bass 10). Abacus C Boxes are originally developed as high-end hi-fi desktop speakers, but they are also used in some professional studios for mixing and mastering. All models are developed and produced in-house by Abacus Electronics UG in Nordenham Germany. The company was founded in 1983. by Mr. Karl-Heiz Sonder and today is run by him and his son, Mr. Hanno Sonder. Today the company, besides active speakers, produces a line of preamps and amps, as well as couple of streaming devices. I have had speakers for more than 3 months and I have been listening to them almost daily with a variety of music, mostly electronic and classical, some jazz and pop/rock and a bit of metal (SACDs, CDs, Blu-ray DVDs, lossy streaming).
User experiences:
-Speakers are quite small. They are also not very heavy, but thanks to the small size and good build, they feel sturdy. When knocked on, housing does not resonate noticeably. Power rocker has good feel to it and two rotating pots feel plasticky (Volume and Bass EQ), but they turn smoothly. The box is completely sealed (acoustic suspension). They are not vinyl-wrapped, but have structural paint on, wich looks and feels a bit utilitarian but high-quality. LED is purple, moderately bright, but offers no info about clipping. Speakers were delivered with two-pin power cables and one wall socket adapter (1 in, 2 out). They came neatly packed in a carefully measured box, wich should be kept for safe transport of the speakers (ring tweeters stick out a few mm out of the speaker cabinets).
-I have the boxes positioned on Stagg budget stands and isolation foam, toed in, distanced about 25cm from the front wall. Distance between the speakers is slightly less than 2m, and listening distance is slightly less than 2.5m. Sidewalls and windows are more than 2m away on both sides. In this setting, speakers sound natural, free of excessive room coloration and the sound stage does not extend much beyond them. Imaging is fairly precise and there is also some hint of third dimension (big screen TV between them works against holography). I had no trouble optimising their placement with small changes, but they do sound horizontally directional though, so no "room filing" sound from these. On the other hand, having ears a bit above or below tweeter level, does not change my sonic experience much.
-They do not get very loud (at least not without bass distortion), so listening above roughly 80dB, even in near to mid-field, is simply not realistic. When the bass EQ is turned on max, which is the default setting for flat response, testing with sine wave generator gives me sensation of usable bass down to about 41-42Hz. Maximum low extension seems to be around 36-37Hz. If one wants to listen at about 75dB to 80dB, it is possible to sacrifice bass extension for SPL by turning the bass EQ down to the minimum. In order to avoid distortion, main volume control also should not to go past half position, unless there is a preamp volume control. Since I have been using them with a preamp, they do not seem to be fussy about being fed with low vs high level signal and having their own volume control higher vs lower.
-Despite a good bass extension for their size, they do not sound like large speakers. They sound like 4" speakers, yet ones supported with a small, extremely well integrated, 5 or 6 inch subwoofer (provided listening levels remain bellow 80dB). It sounds almost as if additional bass drivers are mounted on the back of the speaker cabinets. The bass is fairly deep, if not strong, it is very well defined (fast and distortion-free) and amazingly rich in texture. I can tell a difference between bass guitar and double bass as a difference between night and day. Some bass punch can be heard, certainly not felt, but the best thing about bass is that it does not smear the lower mids (or any other frequency range). Sound of this speaker is complete opposite of being "boomy".
-Mids sound pretty much more natural and correct than any small speaker I have ever heard (Genelec and Neuman included). Female voices sound better than male voices, since the mid-woofer is small. Dynamics of small scale are good, response is very fast, so transients sound very good at lower listening levels. Sound, in general, is open, direct, and the separation of instruments within mid-frequencies is especially good. Smaller instruments simply sound correct, yet pianos sound small, just like symphonic music does not reach much of it's scale, but that is the way it must be with very small speakers. With some distorted and overdriven rock/metal guitars, they do sometimes sound a bit "shouty", but not overly unpleasant.
-Highs are not extremely extended, but what is there is very informative and pleasant sounding, "airy" and nicely rounded (there is no piercing or sibilance). I do not remember I have ever heard subjectively better balance between high-end resolution and absence of listening fatiguing. Even though ring tweeters looks a bit funny in theirs shallow (kind of) waveguides, highs sound as continuous part of the whole frequency spectrum. Cymbals sound like metal discs struck with wooden sticks, not like small air compressors letting out pressurised air, and sure not like someone is rubbing quickly something agains metal. Another good thing about top frequencies is that they are extremely clean, there is not a trace of any hiss, no matter how close I put my ear to the tweeter.
Summary:
It is no surprise that these tiny speakers cannot handle big dynamics good, but fine dynamics are very good. Accordingly, they do not make a great listening tool for big scale orchestral music or epic rock/prog/metal works. Acoustic and vocal music sounds decent enough. What is a bit surprising is that they seem to sound great when reproducing well produced bassy mixture of electronic and non-electronic instruments or progressive electronica (as long as the mix is not extremely busy). Jazz recordings tend to sound particularly exciting, especially if recorded live. Things sound rhythmical and in correct phase, there is no hiss, no hum, and as long the volume is in check, there are no noticeable distortions. Staging and imaging are good and even holographic. Frequencies are reproduced naturally and even smaller details in music are present. Still, beware, these small Abacus boxes are not very forgiving of bad sources. They do not go out of their way to make music sound horrible (or "clinically" analytical), but they also do not give music "make-up" and they pick up electrical noises easily. So, give them decent cables and decent sources with decently produced music and the sound becomes enough "musical" and simply fun and enjoyable that you can forget that you are listening to a pair of 4" two-way active speakers with only 25W per channel at low(ish) living-room levels. They are not cheap, they are spartan, but they are well built and they sound great. If I would to describe Abacus C-Box 3 in 3 words, they would be (in no particular order): Engineered, Natural, Precise. Would I buy them again: Yes. Would I recommend them? Well, if you are into quiet(er) listening of electronica and jazz and do not mind the lack of connectivity, or you simply want "end-game" small desktop speakers, Abacus C-Box 3 speakers are probably the way to go.
Paired equipment: Pioneer DV-575A DVD/SACD Player; Abacus Linetreiber 2020 Variabel Preamp; Acoustic Tuning Cables.
Additional equipment: Sony PS4 Game Console; FiiO BR13 Bluetooth Receiver/DAC.
Pictures:
Cheers.
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