My open baffle journey

@nicoch58 sadly, I don't like the 15OB350, because of the weak bass. But the low Qts tells everything. They sound great down to 100 Hz, really gorgeous, but then the fun ends. With EQ they could be fine, but I'm going passive. So... I will sell them.
Have you heard the SB 15OB350s in an active system and liked the bass driven that way? Just curious since it's been used in a fair number of active builds, and OB bass seems a natural candidate for being driven actively.
 
I have a feeling that a Zenductor 1, with 19V power supply and a higher bias (2A, thus hefty heatsink) will have no problem driving a 4 ohm load. But yes, sonically it would be inferior to the SIT amps. Nevertheless, ir would be interesting to try it out, just for fun...
 
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You do not even need to make active crossover per se. Just add two plate amps behind the woofers. Your signal can go from source through pre and amp without change to fullrange speaker (with cap for high path if it needs it). Plate amp is just sniffing the signal from your amp and feeds the woofers. You obviously need two plate amps. But you get unlimited flexibility. Freedom to select woofers crossover point (does not need to match top), and level, maybe phase. Freedom to use any amp as main, small, big, classA, AB, or D, as long as its comfortable with feeding fullrange driver. Does not need to be able to drive power hungry woofers. No need to match woofers efficiency, no need to lpad the top. Sound signature comes from main amp. I already said this but its no harm to repeat.
 
So it would be a kind of bi-biamping?
Shouldn't the amplifiers have the same power? I control the volume with the preamp. If the main amp is a 25w FW-type and the woofer amplifier is f.e. a 300w Class D, there will inevitably be differences in volume, because the more powerful amp produces a higher volume with the same signal. Okay, a plate amp has adjustable gain, but does that ensure consistent volume/power if there are power differences? My other "concern" is the sound quality of the plate amps. We're trying to achieve high sound quality, and I claim that FW amps, or ZM's amp, or X's amps, etc., deliver very high sound quality - but what about plate amps?
 
Yes, it would be biamping. Mr. Nelson has done exactly this kind of daisy chain biamping...small classA for mid/high and big amp for woofers to follow.
No, they do not need the be the same power, as a matter of fact, they rarely are.
Sound quiality of plate amp depends on the plate amp you select. They come from classD junk to top noth hifi.
 
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One other advantage of biamping is that no matter what happens in plate amp, it does not polute mid/highs. Plenty written about it.
If your main amp distorts, since it has to drive big woofers, distortion harmonics polute mid and up. This does not happen in bi amping. Plus, our ears are more forgiving in low frequencies.
 
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I have a knot... I still don't get how a 300w and a 25w power amp can work together 🤔
With 2,83 volts at the input one gives 25w and the other 300w. If I tame the big one to 25w - where is the advantage?
I have a knot...

Okay, just read your last answer. So I have to tame the big amp to the level of the small amp.
Or - can I use 2 stereo FW-amps too? F.e. Scryer and M2x, one for bass, one for mids/highs?
 
I have a knot... I still don't get how a 300w and a 25w power amp can work together 🤔
With 2,83 volts at the input one gives 25w and the other 300w. If I tame the big one to 25w - where is the advantage?
I have a knot...

Okay, just read your last answer. So I have to tame the big amp to the level of the small amp.
Or - can I use 2 stereo FW-amps too? F.e. Scryer and M2x, one for bass, one for mids/highs?
You are free to use any amp you want. But how is FW amp going to provide adjustable active crossover?
 
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