I recently bought an used pair of Sonus Faber Amatti Homage speakers. I found the sound is diffused. Phase tester result shows that one of the midrange speakers is out of phase. The original owner had replaced one of the midrange speakers by himself but can't tell which side of the speakers he did. My question is do I just reverse the wires on the midrange speaker that is out of phase?
Probably a HT receiver or similar, I'd guess...
Ok, to your specific issue, look at this from the stereophile review
"The Sonus Faber's impulse response (fig.9) is conventional, though some early reflections can be seen. The step response (fig.10) reveals that the tweeter and woofers are connected in positive acoustic polarity, the midrange in inverted polarity. The speaker's cumulative spectral-decay plot (fig.11) is basically clean, but with some very slight modes evident at the top of the midrange unit's passband."
Knowing this, you can verify by taking an AA (UM3) battery to the speaker terminals, with the bi-wire jumpers (if equipped) connected, and watch the cones - the woofers should push out and the midrange suck in.
If one of the speaker's midrange pushes out with the woofers, reverse the leads on that driver as you suggest.
Ok, to your specific issue, look at this from the stereophile review
"The Sonus Faber's impulse response (fig.9) is conventional, though some early reflections can be seen. The step response (fig.10) reveals that the tweeter and woofers are connected in positive acoustic polarity, the midrange in inverted polarity. The speaker's cumulative spectral-decay plot (fig.11) is basically clean, but with some very slight modes evident at the top of the midrange unit's passband."
Knowing this, you can verify by taking an AA (UM3) battery to the speaker terminals, with the bi-wire jumpers (if equipped) connected, and watch the cones - the woofers should push out and the midrange suck in.
If one of the speaker's midrange pushes out with the woofers, reverse the leads on that driver as you suggest.
My “phase” tester is an AA battery.😀
Without the schematic, it’s hard to say. Look at the screws and see if you can tell if they’ve been torqued and screw finish is missing. Barring that, I would connect them both with same polarity and listen.
You could try to measure with REW and see if one loudspeaker has a suck-out in the midrange.
I’ll bet that his solder work is apparent unless SF used terminal connectors.
You will probably be able to tell just by listening.
Without the schematic, it’s hard to say. Look at the screws and see if you can tell if they’ve been torqued and screw finish is missing. Barring that, I would connect them both with same polarity and listen.
You could try to measure with REW and see if one loudspeaker has a suck-out in the midrange.
I’ll bet that his solder work is apparent unless SF used terminal connectors.
You will probably be able to tell just by listening.
Phase tester is a smart phone app and a wav file burnt in a CDR as test signal. Play the CD in the system then move the phone close to the speaker to test. The app will display +, or - .
When playing the CD, I can see the woofers move forward and the tester displaying +, and when I move the tester to the midrange, the phone displaying -
I guess , no matter how the midrange speaker is wired, all speakers must work in phase. With this Sonus Faber，the midrange is wired reversed in polarity in order to get it to work in phase with the rest of speakers.
When playing the CD, I can see the woofers move forward and the tester displaying +, and when I move the tester to the midrange, the phone displaying -
I guess , no matter how the midrange speaker is wired, all speakers must work in phase. With this Sonus Faber，the midrange is wired reversed in polarity in order to get it to work in phase with the rest of speakers.
That sounds right.
If you want a way to choose the preferred polarity without going too deep into it, measure the whole response (move back a few feet first), then reverse the mid and measure again.
If you want a way to choose the preferred polarity without going too deep into it, measure the whole response (move back a few feet first), then reverse the mid and measure again.
if you remove the mids and compare the solderings there should be clues to which one is the original. also, most drivers has different sized terminals to pos and neg, and many speaker mfr's are using quick connectors so there should not be room for connecting a driver with the wrong phase
ok， I took out both mids and I'm surprised to see the mid that was tested out of phase actually has the original soldering !
So, the mids are actually working out of phase with the woofers. Now, it sounds right and much better to my ears , at least the sound is not diffused. Thank you all !
So, the mids are actually working out of phase with the woofers. Now, it sounds right and much better to my ears , at least the sound is not diffused. Thank you all !