The Fusion has a dc protection, but with all dc protection it may be not fast enough. If you use a expensive tweeter it would be wise to use a capacitor calculated several octaves below the x-over point you want to use. Do all your measurements with this capacitor.
On small free tip: if your tweeter needs a lot of padding down, use a series resistor. You will get current drive if the resistor is large enough so it will reduce distortion.... This will work with pure restistive loads like AMT or planars.
On small free tip: if your tweeter needs a lot of padding down, use a series resistor. You will get current drive if the resistor is large enough so it will reduce distortion.... This will work with pure restistive loads like AMT or planars.
Thank you for replay
The thing is that I would like to use best quality parts I can in my build
And those large "audiophile" capacitors cost more than tweeters in self...
Or it would be ( more or less) less expensive to build complete pasive crossover than to use amplifier and large capacitor
...
Will have to think
Maybe to continue using it without protection as up to now...
Will see...
The thing is that I would like to use best quality parts I can in my build
And those large "audiophile" capacitors cost more than tweeters in self...
Or it would be ( more or less) less expensive to build complete pasive crossover than to use amplifier and large capacitor
...Will have to think
Maybe to continue using it without protection as up to now
...Will see...
In general, current drive brings very little to no benefits in already low distorting tweeters models with copper sleeve inside of the motor where inductance is almost nonexistent. Resistance padding is great from noise consideration and here DSP system can be similar to passive. +1 for capacitor for tweeter safety , I have lost two DXT tweeters, both from my stupidity and lack of capacitor. Panasonic ECQ polyester capacitors are best for the task and you don't have to buy audiophile scam in order to protect tweeters several octaves down from operating frequency.
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There is very little correlation between "expensive audiophile stuff" and "best quality". Capacitors that are good enough to use in space, in airplanes and hospitals running critical gear don't cost that much.
Fortunately cardiologists usually don't bother with 1% distortion of ECG graphs so they don't mind using mediocre capacitors in there.
Fortunately cardiologists usually don't bother with 1% distortion of ECG graphs so they don't mind using mediocre capacitors in there.
If you compensate for the effect of the cap in your crossover settings (ie if you manage to get a given acoustical target) then you can shoot for a smaller cap/higher 1st order HP frequency.Thank you for replay
The thing is that I would like to use best quality parts I can in my build
And those large "audiophile" capacitors cost more than tweeters in self...
Or it would be ( more or less) less expensive to build complete pasive crossover than to use amplifier and large capacitor
Will have to think
Maybe to continue using it without protection as up to now
Will see...
It is better to have the corner frequency lower than the impedance peaks, so you don't get peaks that will be difficult to handle in the stop band (by the way, you will get that sort of things with a series resistor...).
Using a higher impedance tweeter (eg 16 ohms instead of 8 ohms) will also let you use smaller / less expensive caps for the same corner frequency (and also reduce hiss/noise, which is always good with high sensitivity drivers)
I don't want to get into an audiophile debate, but in my experience, most capacitors have their own sound signature in passive filtering and a more expensive capacitor is not necessarily better, just different.
There is DC protection in the Fusionamp and (fortunately) we can now avoid passive filtering in a relatively simple way.
So I would say, if someone is worrying and the sound is good enough for him with the capacitor in the path, then use it. I do not use.
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Indeed, debating with a True Audiophile is about as fruitful as a debate with those two nice young men in suits that occasionally turn up at my front door. Instead, being the boring engineer I am, I tend to ask for objective, verified evidence.
Then why was it a question of using a capacitor or not?
According to these, it is clear that we use it because it does not spoil the sound, but protects it from DC, and the frequency response with DSP can be easily compensated.
Original question answered from an "objective" point of view.
I was addressing the "most capacitors" part. Large electrolytics can be non-linear.
As soon as capacitor is more expensive than a tweeter, no.
The other part of the discussion is nonsense becouse capacitor-controlled filter acts way below pass-band of the tweeter and it is impossible to hear it..
I would not compensate capacitor filter response in the DSP becouse then we acts counterintuitively and just negate using capacitor then.
So just because the sensitivity decreases? Sure, but that will not just attenuate noise and hiss, it will attenuate the music too. You could use an extremely inefficient tweeter for even better result
Tweeters are usually more sensitive than mids/woofers (eg 96dB in yoke's case) in typical builds.
This is of course especially true with compression drivers.
Using a less sensitive tweeter would not be different than using a lpad, and you would be burning Watts.
Not very satisfying, especially when power is limited and better used on less sensitive drivers in a plate amp.
I use an autoformer set to -12dB (16x the impedance) to mate a 8 ohms compression driver to an AS2-100D. This gives adequate sensitivity matching with an 8" hifi woofer (even when constant directivity is taken into account) and reduces hiss to a point of being just inaudible past 30cm. That way almost the full 100W of the power supply are available for the 100W amp on the woofer.
But that is another passive component, that also has a cost...
Higher impedance also reduces distortion
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Sure, it makes sense if you would have to attenuate anyway - but the attenuation (L-pad or transformer/autoformer) would reduce the noise/hiss just the same, so in that respect the higher impedance makes no difference.
Higher impedance also reduces distortion
I haven't seen any measurements of the Hypex amps showing THD as a function of load impedance.
Thank you all for replay...
I have to point that I'm not an expert in any way. I like diy audio and for me it's like LEGOs
For that reason I go active, as I can change settings in couple clicks
In my previous builds I haven't got problem with brumm..hisss...etc...
But now, with high sensitivity tweeter and high gain, high power amplifier connected directly on it I have hissssss, which is very, very audible.
(I don't blame DSP for it, don't blame amplifier or tweeter, but I have this combination which is not working for me)
So I'm looking for all solution.
One was to add L pad and lower sensitivity of tweeter (If I get that right)
That way I would lower hissss sound which is constant and I can always rise the music signal (I hope)
(as now I have -16db on tweeter and like -5 and -4 on mid bass and bass - amplifiers are hypex 252+nc100hf)
I didn't wont to start debate about sound Q of different capacitors, sorry about that...
I was hoping that DC protection in hypex is good enough that we can trust it
That' s the reason why I post this question...
I think that solution for my problem would be an amplifier with less power and gain...
but once I start asking question, people state out, why I don't have capacitor in front of tweeter for protection
Now I will try some capacitor (no meter what price range, audiophile or not) and try the blind test...
But have to worn you all that I have very sensitive hearing, as I can hear changings in my setup, that I made via PC/DSP software and without even DSP connected to PC !!!
So I'm real audiophile !!!
Thank you all for advices, I really appreciate it
I have to point that I'm not an expert in any way. I like diy audio and for me it's like LEGOs
For that reason I go active, as I can change settings in couple clicks
In my previous builds I haven't got problem with brumm..hisss...etc...
But now, with high sensitivity tweeter and high gain, high power amplifier connected directly on it I have hissssss, which is very, very audible.
(I don't blame DSP for it, don't blame amplifier or tweeter, but I have this combination which is not working for me)
So I'm looking for all solution.
One was to add L pad and lower sensitivity of tweeter (If I get that right)
That way I would lower hissss sound which is constant and I can always rise the music signal (I hope)
(as now I have -16db on tweeter and like -5 and -4 on mid bass and bass - amplifiers are hypex 252+nc100hf)
I didn't wont to start debate about sound Q of different capacitors, sorry about that...
I was hoping that DC protection in hypex is good enough that we can trust it
That' s the reason why I post this question...
I think that solution for my problem would be an amplifier with less power and gain...
but once I start asking question, people state out, why I don't have capacitor in front of tweeter for protection
Now I will try some capacitor (no meter what price range, audiophile or not) and try the blind test...
But have to worn you all that I have very sensitive hearing, as I can hear changings in my setup, that I made via PC/DSP software and without even DSP connected to PC !!!
So I'm real audiophile !!!
Thank you all for advices, I really appreciate it