And, again, why would it need to be any "faster" than what is required to reproduce 20 kHz at full output amplitude? Remember that class D amps are usually bandwidth-limited on the input.
Yes, SNR, distortion (both harmonic and intermodulation) and output power are of course important. Ability to reproduce square waves isn't.
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DjLeco, I just realized you seem to have continued a completely different thread in this thread for some reason. What does this have to do with Class II safety?
This thread is discussing electrical safety considerations related to the Hypex modules. If you have some issue with regards to reproducing square waves, I suggest you start a separate thread, or keep the discussion to the measurement thread you started.
Similar question, SMPS400A180+UcD180 safety
I too intend to use RCA inputs to my Hypex amp. I shall connect mains ground pin to the chassis. SMPS is grounded through metal spacer at J7. SMPS output ground connected to UcD ground tab. My RCA connectors have plastic insulation washers-should I fit them?
Martin
I too intend to use RCA inputs to my Hypex amp. I shall connect mains ground pin to the chassis. SMPS is grounded through metal spacer at J7. SMPS output ground connected to UcD ground tab. My RCA connectors have plastic insulation washers-should I fit them?
Martin
I assume you have good reasons to use RCA's instead of XLR connectors. If so, I would recommend isolating the RCAs, and connecting their "cold" ends to chassis ground with a small resistor in parallel with a small capacitor.
Thank you. The amp will be fed by a miniDSP 4x10HD which is known to be noisier through its balanced output than its RCA's. What is the consequence of not tying the RCA 'cold' end to ground? Which is the 'cold' end (sorry)?
Martin
Probably like many he does not understand the distinction between class 1 and class 2 safety classifications. I'm sure it was an honest mistake, no need to get your knickers in a twist... seriously.. 😀
Rather unfortunate design - usually balanced provides more noise margin rather than less.
Potentially nasty noise issues.
The ring - the one that would be connected to the chassis in an unbalanced amp (as opposed to the "hot" central pin).
Preferably yes, and ground as close to the RCA connector a possible (so chassis), in order to shunt off any incoming noise.
No.
The signals should be isolated from the chassis/enclosure.
One can add small low impedance capacitors from signal to enclosure at the input sockets and at the output sockets. But this hand/hardwiring is time consuming and rarely implemented.
I attach a 47pF across the hot to cold at the socket to attenuate differential noise.
I sometimes attach 22pF from both signal wires of the input socket to the chassis at the input socket to attenuate common mode noise.
I sometimes add 1nF from both speaker signals (hot and cold) to the chassis at the output socket. This to attenuate common mode noise.
I always add a Zobel across the speaker output socket to attenuate differential noise.
I was (and still am) assuming that when U33446z was asking about "separate connection to ground", it was in response to my recommendation of connecting their "cold" ends to chassis ground with a small resistor in parallel with a small capacitor. Hypex recommends 100 ohm and 100 nF.
If you connect mains earth to chassis the inputs should not be left fully floating.
What if your mains do not have earth. Im Denmark it's not normal with earth in mains.
Then you don't need to isolate the inputs, but make sure you follow Class 2 safety guidelines.
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