You know, I read this quote and thought of it out of context. I was referring to a potential XA252 balanced version which would likely null out the 2nd harmonic distortion if special care wasn't taken to make sure that did not happen.
Is there a special requirement for the green LED or are all 3 mm versions okay? There are many different specifications. Or can it even be blue (I have these in large quantities, I would have to order green)?
sweet and short - don't do that
99% nothing will go puff, but it'll sound as drek
inactive preamp will act as heavy parasitic load to active preamp
regular non- bridged OS asking for one SIT per channel
bridged OS asking for 2 SITs per channel
so - more, no bigger
when you find bigger ones, send them all to OPLDF, they're not good for ........ anything
most common type you can find - diffuse, no special brightness, no special big current, supposed voltage across is 1V93 @ few mA
Lite-On LTL-1CHGE, just frirst one adequate I snatched from gglsrch
I have ordered 4 of those, checked mouser and digikey, one out one had less than 20. Mouser showed a fairly long lead time.
These will do. Can always be changed, but unless for some odd reason "sound worse" than the standard ones I generally use, and that is hardly likely. They do look cool. Pricey, but I've waited to build this for some time and all the difficult Preliminary work is done. Wiring and correcting any smoke escape is left.
Russellc
Does "bridging" also share the trait (like balanced) of canceling 2nd order distortion? If so, tricks to restore it?, not needed, or different but fine?
Russellc
in general - whenever you have symmetrical circuit (be it "just" push pull OS , or really bridged), that tends to cancel even harmonics, leaving 3rd harmonic as dominant
now, how much of these (even) will left in THD Spectra, depending of constructor - that can be either matter of happenstance (so no deliberate) or deliberate
from my corner, I'm always shooting for deliberate spoiling of that symmetry, ending with dominant 2nd, hopefully* neg phase, hopefully* through entire power range
*if/as much possible
anecdote mode On - Babelfish XA252 intrinsically is 3rd dominant circuit; it took some fiddling time to make it 2nd dominant, in all 3 iterations, and as much broad power range; easily seen on all THD graph I posted
anecdote mode Off
now, how much of these (even) will left in THD Spectra, depending of constructor - that can be either matter of happenstance (so no deliberate) or deliberate
from my corner, I'm always shooting for deliberate spoiling of that symmetry, ending with dominant 2nd, hopefully* neg phase, hopefully* through entire power range
*if/as much possible
anecdote mode On - Babelfish XA252 intrinsically is 3rd dominant circuit; it took some fiddling time to make it 2nd dominant, in all 3 iterations, and as much broad power range; easily seen on all THD graph I posted
anecdote mode Off
Ok. So now if big bada version emerges, no fear of not being able to twiddle in some hopefully second order. Now I am again looking at BBA3 parts box.....
Russellc
Russellc
^ "If not Boeing, I'm not goeing"
I used to work at the Spring Factory... you know... boing! boing!
Airbus is weird, their cockpit design is a video game.
Good to hear about keeping 2nd order harmonic... negative 2nd order... I recall Nelson talking about that at BA23.
I used to work at the Spring Factory... you know... boing! boing!
Airbus is weird, their cockpit design is a video game.
Good to hear about keeping 2nd order harmonic... negative 2nd order... I recall Nelson talking about that at BA23.
Hi,
I found a picture of the Pass XA160 and if I see it correctly, then the PSU is not a CRC, but only built with buffer capacitors.
The XA600, on the other hand, has CRC PSU. Does anyone have an explanation? Is CRC not a "must"?
I found a picture of the Pass XA160 and if I see it correctly, then the PSU is not a CRC, but only built with buffer capacitors.
The XA600, on the other hand, has CRC PSU. Does anyone have an explanation? Is CRC not a "must"?
He doesn’t mention about this one but it’s not so important as long as you can reverse the speaker polarity. This way you can also easily find if you like positive or negative phase 2nd hd.
^ ".. reverse the speaker polarity..."
Huh? The phase of the 2nd order harmonic, positive or negative, is relative to the fundamental.
if you reverse the polarity, you are reversing both the distortion elements AND the fundamental. Huh?
Huh? The phase of the 2nd order harmonic, positive or negative, is relative to the fundamental.
if you reverse the polarity, you are reversing both the distortion elements AND the fundamental. Huh?
CRC is only for class AX600, of course. But the question remains the samethis one with CRC, the one above without:
View attachment 1226205
ohh... of course, thanks, I was somewhat confused...