The above discussions of bridging SS amps are pretty good, but to make a point--bridged amps are NOT 'high-current' amps. Only if an amp has a 4-Ohm rating that's double its 8-Ohm rating will it be able to drive FOUR times the power into 8 Ohms--and four times is the theoretical amount. So if your speakers are 4-Ohm rated or are relatively insensitive...say below 90dB...don't look for a bridged amp. However, the channels of any SS amp can be paralleled, just as the channels of a tubed amp can. Simply drive both inputs with a Y-connector and wire the output terminals in parallel and you have a mono amp with the combined power of the 2 channels. IOW, if you had a 125-into-8 stereo amp, when paralleled it becomes a 250-into-8 amp.
I think passive biamping makes sense only when you intend to use amps that are (more or less) well suited to driving parts of the audio spectrum. Let's say you have a overall sweet-sounding amp that just doesn't have enough power to produce the bass 'slam' diddeeboppers love. Connect it to the MR/treble part of your 3-ways and buy a SS amp noted for its bass performance. After level matching, you have what MAY turn out to be a QUITE-fine-sounding amp system.
IMO, biamping AND biwiring benefit equally from using speakercable selected to carry parts of the audio spectrum, same as amps. If driving bass only, select a cable with lots of material for low resistance but that's still inexpensive, such as AQ's Type 6. For MR/treble, select a cable that has excellent material and geometry for critical listening but that's not too high in gage or expensive. For this, I'd use AQ's DBS-type CV-6 or KE-6, both using 4 pairs of 4-different-size conductors. If driving treble only, I'd use AQ's all-silver, DBS-type KE-4 at half the price of KE-6.
All of this is controversial, but my experience over the decades supports it. As always, listen carefully and be cautious.
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I think passive biamping makes sense only when you intend to use amps that are (more or less) well suited to driving parts of the audio spectrum. Let's say you have a overall sweet-sounding amp that just doesn't have enough power to produce the bass 'slam' diddeeboppers love. Connect it to the MR/treble part of your 3-ways and buy a SS amp noted for its bass performance. After level matching, you have what MAY turn out to be a QUITE-fine-sounding amp system.
IMO, biamping AND biwiring benefit equally from using speakercable selected to carry parts of the audio spectrum, same as amps. If driving bass only, select a cable with lots of material for low resistance but that's still inexpensive, such as AQ's Type 6. For MR/treble, select a cable that has excellent material and geometry for critical listening but that's not too high in gage or expensive. For this, I'd use AQ's DBS-type CV-6 or KE-6, both using 4 pairs of 4-different-size conductors. If driving treble only, I'd use AQ's all-silver, DBS-type KE-4 at half the price of KE-6.
All of this is controversial, but my experience over the decades supports it. As always, listen carefully and be cautious.
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