^Obviously you have a quite high crossover then. Subwoofers and their xo slopes are very difficult to measure indoors. You should also measure the main speakers and their highpass slope...
Other option is to abandon all measurements and only trust your ears. Whatever settings that sound good!
Other option is to abandon all measurements and only trust your ears. Whatever settings that sound good!
I tested without the main speakers.
The xover was set to 50hz LR 4th order.
One of the possibility was the 3m sub located at middle of the right wall where the strongest room mode was.
Maybe I lower the volume to minus, and trying invert one sub for fine tuning.
well, in fact, I was sure I had used relative delays in MiniDSP NanoDigi8, but I checked, they were absolute delays too.
I tried absolute delays today with the FusionAmps, but the result is simply awful. The story is complicated, as I use a software switch (Acourate Convolver) to split the source in 2 channels : a "half" 120Hz XO for the low frequencies sent to Tact amplifiers, and all freqs above 120Hz sent to the FusionAmps DSPs.
So I have already a 1.2ms delay on the low freq channel to deal with the Hypex DSP delay.
The acoustical delays have been quite accurately defined through sineWave convolution of recorded pulses. I ought to use a 3.390ms delay for the lower medium. As the delays are absolute, I added the upper medium delay (80us) for channel 2, so 3.47ms, and the tweeter delay (60us) to that figure, so for channel 3 : 3,53ms but the result is absolutely not satisfactory...
The woofers-lower medium delays being most probably of no use (and probably wrong), I should probably try absolute delays with the lower medium as reference, not the woofers
Let me say that the result is already astonishingly good without delays...
I tried absolute delays today with the FusionAmps, but the result is simply awful. The story is complicated, as I use a software switch (Acourate Convolver) to split the source in 2 channels : a "half" 120Hz XO for the low frequencies sent to Tact amplifiers, and all freqs above 120Hz sent to the FusionAmps DSPs.
So I have already a 1.2ms delay on the low freq channel to deal with the Hypex DSP delay.
The acoustical delays have been quite accurately defined through sineWave convolution of recorded pulses. I ought to use a 3.390ms delay for the lower medium. As the delays are absolute, I added the upper medium delay (80us) for channel 2, so 3.47ms, and the tweeter delay (60us) to that figure, so for channel 3 : 3,53ms but the result is absolutely not satisfactory...
The woofers-lower medium delays being most probably of no use (and probably wrong), I should probably try absolute delays with the lower medium as reference, not the woofers
Let me say that the result is already astonishingly good without delays...
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Back on the delay question.
I had the opportunity to measure the DSP+NCore delays with an oscilloscope + wave generator.
We found an almost 1.2ms delay (1180us at 120Hz), the same as mentioned higher in the thread.
But the delay decreases when you check at higher frequencies : 495us at 1kHz and 352us at 7.5kHz, my 2 higher XO frequencies
Meaning that this delays question is quite complicated in fact, not only a matter of knowing if it is absolute or relative. So acoustical measurement might well be the only way to assess it properly...
By the way, I tried to get the "pure" DSP signals rather than the ones at the NCore outputs, but disconnecting J4 in order to pick up the DSP's outputs seems to stop the DSP. I guess a mute circuit matter. Any walkaround for that ? (measuring delays through the NCore is a bit difficult, because of the 400kHz carrier frequency giving a very unaccurate sinewave, though we succeeded with a superimposed 10Hz square wave as reference...)
I had the opportunity to measure the DSP+NCore delays with an oscilloscope + wave generator.
We found an almost 1.2ms delay (1180us at 120Hz), the same as mentioned higher in the thread.
But the delay decreases when you check at higher frequencies : 495us at 1kHz and 352us at 7.5kHz, my 2 higher XO frequencies
Meaning that this delays question is quite complicated in fact, not only a matter of knowing if it is absolute or relative. So acoustical measurement might well be the only way to assess it properly...
By the way, I tried to get the "pure" DSP signals rather than the ones at the NCore outputs, but disconnecting J4 in order to pick up the DSP's outputs seems to stop the DSP. I guess a mute circuit matter. Any walkaround for that ? (measuring delays through the NCore is a bit difficult, because of the 400kHz carrier frequency giving a very unaccurate sinewave, though we succeeded with a superimposed 10Hz square wave as reference...)
Hello.
I have some passive speakers rated for 200W- they have a 3.8 ohm compression driver and a pair of 10 ohm 6” woofers. I am interested in rocking some plate amps to stop relying on receiver amps. My plan is to stick them in an aluminium box and wire the amp to the back of the speaker.
This is the box:
https://www.budind.com/pdf/hb401.pdf
6"w
14" d
3" h
.050 thick
⅛ lbs
BPA-1514
I assume we want something thicker than 0.05” thick? I am still looking into having the box cut and coated.
On the back of a speaker, the amp box will be inches from the speaker’s binding posts. I was thinking of just popping the speaker wire out of a hole. Should I add binding posts on my amp box out of the FA251 to my speaker?
I’m between the FA122 and the FA251. From what I’ve read the single driver is the way to go for a passive speaker. So it looks like the FA251 is the way to go for me if I don't rip out the crossovers.
Any thoughts on using the high level inputs for a full range speaker? I’m curious about using these on a weak receiver with no pre outs.
Will hypex solder the gain jumper with an order? One receiver I am looking at does 2V for the XLR.
Thanks in advance to answering my questions. My end goal is a nice home setup.
Cheers!
I have some passive speakers rated for 200W- they have a 3.8 ohm compression driver and a pair of 10 ohm 6” woofers. I am interested in rocking some plate amps to stop relying on receiver amps. My plan is to stick them in an aluminium box and wire the amp to the back of the speaker.
This is the box:
https://www.budind.com/pdf/hb401.pdf
6"w
14" d
3" h
.050 thick
⅛ lbs
BPA-1514
I assume we want something thicker than 0.05” thick? I am still looking into having the box cut and coated.
On the back of a speaker, the amp box will be inches from the speaker’s binding posts. I was thinking of just popping the speaker wire out of a hole. Should I add binding posts on my amp box out of the FA251 to my speaker?
I’m between the FA122 and the FA251. From what I’ve read the single driver is the way to go for a passive speaker. So it looks like the FA251 is the way to go for me if I don't rip out the crossovers.
Any thoughts on using the high level inputs for a full range speaker? I’m curious about using these on a weak receiver with no pre outs.
Will hypex solder the gain jumper with an order? One receiver I am looking at does 2V for the XLR.
Thanks in advance to answering my questions. My end goal is a nice home setup.
Cheers!
Hi, would anyone be so nice and tell me if I am at the right address when considering using the FA 253/503 as a replacement for hiend passive corossover in my speakers (Visaton TIW300, SS 8531, BG NEO10+NEO3)? Can I kick out my external DAC and power amp (Rotel RHB-10)? Is it supposed to play better? Thank you
You can chain as many Fusion amps as you want for as many drivers as you want.
The only limitation is that a single Fusion amp can't output a stereo output, all outputs per Fusion amp are either left channel or right channel or mono'd left+right.
So one could use per speaker an FA123 driving 2 woofers + tweeter and an FA122 in BTL driving the subwoofer. Times two for the other speaker. Will work perfectly all linked with SPDIF cables.
I have one question, is it possible to use a FA122 and bridge the two amps to 250 Watt at 4 Ohm for one channel while only using the DSP features for the other channel? I have in mind to use the FA122 as a Subwoofer Modul but then also link the active tops and still have the benefit to use DSP for EQ and Delay. I'm also not afraid to solder anything to connect a second line output. I'm just not sure which pins/signal paths to use. thanks in advance.