mswlogo;545306 Wrote: > Not really. It's not a digital amp. It's not a class D amp. > > Tuning amps to each frequencies is applicable in both. > > But the power needs using passive crossovers is the same in active and > passive. > > Some actives convert to digital, do crossovers, then back to analog. > But adding a to d and d to a has other issues.
Not sure what you mean by "power needs" here. One of the (many) advantages of active vs. passive is that active is much more efficient because there are no lossses in the (passive) crossover network and the load is much more predictable in terms of damping factor/impedance/current draw. All of this means smaller power amps can be used for the same delivered sound level. It also means that at high power levels there is less stress on the power amps. Active also buys you a usable frequency response that is far less constrained by the speaker cabinet than passive designs. All of the above is true regardless of the x-over being digital or analogue. The main reason for using digital x-overs is so that filter slopes and other funkier things like bass shaping, driver time alignment, phasing etc can be made as complex/precise as required much more easily (and at much less cost) than analogue line-level x-overs. High-quality analogue line-level crossovers are expensive. However, to give the digital x-over (which is simply a bunch of clever DSP) the best circumstances to work in, level control needs to be placed AFTER the x-overs for all of the reasons (SNR etc) discussed in this and related threads. Hence Meridians "speaker link" interface that sends "volume" meta data (control sgnals) to an electronically controlled analogue gain stage located post-DAC, just prior to each power amp. This is their "hybrid" solution. This is how the DSP speakers and the G91 all-in-one device work. The G68 is something different. When connected to Meridian DSP speakers it will behave as described above, sending meta data rather than manipulating the digital bitstream. However, if a normal "amp" is connected to its analogue outputs, volume control is achieved using DSP alone.... UNLESS Meridian have included a similar analogue gain circuit after the output DAC(s) - which is possible, although the datasheet implies otherwise. If the s/pdif output from the G68 has a variable level, this must be accomplished by DSP alone. When connected to DSP speakers via "speaker link", the s/pdif must be fixed level. -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... Touch(wired/XP) - TACT 2.2X (Linear PSU) + Good Vibrations S/W - MF Triplethreat(Audiocom full mods) - Linn 5103 - Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Townsend Supertweeters, Blue Jeans Digital,Kimber Speaker & Chord Interconnect cables Kitchen Boom, Outdoors: SB Radio ------------------------------------------------------------------------ Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=78477 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
