
TheCBM-170’scrossoveremploysair-coreinductors and polyester film bypassinductors.Allsectionsaresecond
order,andtheyformfourth-orderhigh-passandlow-passfilterswhencombinedwiththenaturalrolloffofthedrivers.
The electrical crossover frequency is 2.2 kHz, with the actual, acoustic point being somewhat lower in frequency. The
tweeter also has a Zobel network and the woofer has an additional second-order, low-pass filter, forming a true
fourth-order electrical low-pass filter that only has an effect well above the crossover point. This is pretty serious
crossover work for a system in this price category.
Therated response is74 Hzto20kHz (+/- 2dB), theminus3dB point issaidtobe 69 Hz,the nominalimpedance
isabitunder 8 ohms(4.1-ohmminimumat200Hz),andthe input sensitivity(2.83voltsapplied)isatypicallyaverage
89 dB. The speaker can get along with amplifiers as low in output as 35 watts per channel (it would be hard to finda
decent, modern amp with that little power, of course), and it can handle momentary program peaks of up to 200
watts.Theconnectionsontherearmakeuseofgold-plated,5-waybindingpostsandthereisapairof_-inch,number-
20, threaded inserts on the back that will allow the system to be attached to a sturdy wall bracket. To insure that the
wall bracket will probably not pull loose, the CBM-170 weighs in at a modest 13 pounds. The speaker has a limited
five-year, transferable warranty.
Thesystemwouldnormallybepositionedvertically,with the tweeter above the woofer/midrange. However,for
center-channel use it can be placed on its side. The standard version has the company logo on the narrow end of the
grill screen, but the version configured for center use has it on the long edge and turned so that it does not look odd
withthespeakerplacedhorizontally.Otherthanthegrill-logodifferenceandthedifferentpositionoftheidentification
sticker on the back, the center version of the CBM-170 is identical to systems designated for left-right main and left-
right surround use.
Horizontal positioning with a speaker of this kind eliminates some of the more obnoxious interference-effect
problems you would get with all-too-common, horizontally positioned MTM center speakers. However, you would
stillgetsomelobingat certain off-axisangles.Forthebestcenter-channelperformance,theusermight try toorientthe
system vertically to see if it offers a significant improvement over horizontal placement. You would want to use the
vertical-oriented version of the grill if you placed the unit that way permanently.
NormallyIlistentospeakersbeforeIdoanymeasuring.However,myfirstexperiencewiththesespeakersinvolved
settingupa stereo pairof themin combinationwith aHsu VTF-2in myroughly 18x 22x 8.5-footmain listeningroom
and doing my usual series of moving-microphone, 20-second integration curves with my AudioControl SA-3051
RTA.For this session,I usedtheOnkyoTX-DS787 receiver I reviewedinissue86 and madeuse ofitssub-outjack and
internal,80-Hzcrossover.TheDVDplayerusewiththeDelosSurroundSpectaculartestdiscwasadiscontinuedSamsung
unit.Giventhecleandesignandminimalistapproach,Iexpectedtoseedecentperformancefromthesystems.However,
IwaspleasantlysurprisedtodiscoverthattheydeliveredsomeofthemostattractiveroomcurvesIhaveevermeasured
in that particular room.
After placing them on 28-inch-high stands about 2.5 feet from the front wall and centered 9 feet apart (about 6.5
feet from the side walls), I got a best-curve measurement that was +/- 3 dB from 63 Hz on up to 18 kHz. Better yet,
overthecritical midrange between250 Hzand 2.5kHz thevariationwasonly+/- 2 dB,which wouldbe aremarkable
achievement for even a considerably more expensive speaker.
Inaddition,whilemosttwo-waysystemsexhibit a dip of some sortsatthecrossoverpoint(insomecases,thisdip
can be substantial), the transition from woofer/mid to tweeter with the CBM-170 was considerably smoother than
most. Indeed, of the two-way systems I have reviewed, only the Waveform MC satellite, Dunlavy SC-II, and Atlantic
Technology 271LR satellite have surpassed the Ascend in that area – but not by much. And all of these systems cost
more than the Ascend model, with the first two costing a great deal more.
Indeed, the overall response-curve uniformity of the Ascend/Hsu combination was comparable to that of the
Waveform MC/MC.1 sub/sat package that I reviewed in issue 84, and even to the Dunlavy Cantatas I reviewed in
issue87. Kids, thissub/satpackageis right upthereplaying in thebigleagueswhen it comestolinearpower input to
a typical listening room.
A few days after doing the measurements I did a series of single-presentation auditions with a number of fine
recordings that have recently come my way. I used a different package of ancillary gear for these listening sessions,
including a Pioneer DVL-700 super-combi player (reviewed by me in issue 66), a pair of Sherbourn 1/300MB power
amps,avintageCarverC-1 preamp, and the AudioControlPhase Coupled Activator (thatI reviewed in issue68). The
PCA, in addition to its bass-synthesizing abilities, incorporates a separate, Linkwitz-Riley crossover with fourth-
order filters set at 90 Hz. The crossover was used to separate the sub input from that to the satellites.
Particularly impressive was a recording ofCantiones Sacrae Quinis Vocibus, by Peter Philips, as performedby the
Tudor Consort (Naxos 8.555056). The sound was absolutely superior and the performance was utterly profound. The
CBM-170 pair managed to bring out all the fine technical qualities of this presentation. Just as impressive sounding
with the speakers was a recording of An American Requiem, by Richard Danielpour (Reference Recordings RR97CD),
which is as fine an example of a massed choral group recording as I have ever heard.
A bit livelier was Danzón, performed by the Turtle Island String Quartet (Koch 7529). This mix of jazz and Latin
musical themes, with a bit of classical thrown in, exhibited very good detail, imaging, and clarity and it helped to
showcase the ability of the Ascend systems to delineate those qualities. The result was very impressive.