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Just another little thing - I see that the CA48 has a "Brilliance" setting. If the Philips lack bass, try reducing brilliance. (and then perhaps also turn the volume up slightly).
From what ECBetancor is saying, it appears that the bass-light Philips might suit the CA48, but if you still think there isn't enough, maybe the Brilliance setting will help. It'd be better if it had a separate adjustment for bass, of course. You could always add an external equaliser.

Greg

That’s indeed some great advice, Greg. I would definitely look into some cheap AMPs in the near future, should the sound comes from the Philips become unbearable. I was just shocked that my false expectations could change things so dramatically.

Also, when you get something for free, you’d be looking them down a bit, the Sony is indeed a good pair for listening to music, now that I think about it:)

As an owner of a CA48, I really don’t want to agree with you, but it seems that’s indeed the fact. I was surprised that to dive a 32ohm headphone, I would need to set the volume to 90% on the CA48. So sad.

I couldn’t agree more with the flat response part, that’s also the reason I bought the Philips in the first place. Btw, I have a pair of Samson SR850 incoming, seems it’s currently clearing custom, and I should be able to get them within days. I’ll compare the two when I get my hands on them.

I suppose that’s another interesting thing to try, up until now the brilliance setting on my CA48 has been default, I’ll try to mess with it a little bit to see how it goes.

Also, as I mentioned on the above post, I’ll try to compare the Samson SR850 with the Philips, and see which ones are better. I’ll keep both, though, cause the SR850 only cost me less than $30, even they are a complete bust, I could still live with it.

Try some inexpensive headphones to be sure there is not a defect in the headphone output stage.

Setting the volume to near max is not ideal. If the headphone output stage clips, it might damage your headphones. However, clipping may only be a transient phenomenon, such as when you strike a fortissimo high note, so you may not notice it generally.

I'm still of the opinion that even if the volume has to be set to 100%, and it's loud enough, you're sweet. Yes, in the event you hear distortion, reduce the volume, and if that's then not loud enough, get an amp, or different headphones.

A headphone amp can be overloaded even if the volume is not at or near maximum, with the "right" headphones.

When trying new headphones, always set the volume to zero when you plug them in, and then gradually turn the volume up. (common sense)


Greg.

Thinking about this further, IMHO, if a DP's headphone output ever clipped NOT due to excessive current draw from the headphones, but from the internal signal level being too much for the headphone amp to handle (causing the output to clip), I'd consider that a design defect.

My P-515 has this kind of defect, with Bluetooth. If I feed it a 100% level signal using Bluetooth, it clips, regardless of the headphone output volume. It's clipping internally. Solution: I set my Bluetooth device's volume a bit under 100%.

Greg.

Sorry me again
Going by the specs, I predict that those Samsons will be 3dB quieter than the Phillips. (which is "a little bit" quieter).

Also, if the Philips were able to get loud on the smartphone, I think they're working fine.

This headphone nut really, REALLY likes those Philips SHP9500 phones: https://www.youtube.com/watch?v=aipXii-qWiQ

Greg

There are amplifiers that have limiters or soft clipping circuits (for instance, some NAD consumer stereo amps have soft clipping filters) but I would be very surprised if the headphone op-amp chips in typical DP's have these features. It usually is a combination of audio content and amplifier gain that results in clipping.

Kawai have full control over the signal that is fed to the headphone output. Again - I would find it very unusual for them to allow that signal to ever be high enough in amplitude to cause voltage related clipping - even with the volume at 100%. I also think that if it does have an output impedance of 50 to 100 ohms, the chances of current overload are virtually nil.

Can clipped audio *content* cause damage to headphones? If so, we could be in trouble, because I've read that clipping is fairly common in modern music. (but I've never heard any)

Re my Bluetooth clipping issue on the P-515 - it's definitely an outlier. Every other device I've tried allows my Bluetooth level to be at 100%.

Greg

Note that the SHP9500 has a maximum power of 200mW, which equates to 2.5V RMS. From everything I've seen here, the CA48 is not getting anywhere *near* that level. Even if clipping were to occur, in order for damage to occur, it has to have enough energy to do so.

Greg

I'm not familiar with this keyboard but many DP's have audio inputs that allow other signals to be played through the headphones.

Flattening of a waveform can introduce high frequency terms to the waveform. This can damage a tweeter in a conventional speaker, but the headphones may have a very wide frequency response range.

In any case, the first order of business should be to determine if the problem is that there is a defect in the piano or that the headphones are just inefficient.

Fair point - I agree that it may not be always possible to prevent clipping somewhere in the chain, but even in that example, it would still be simple to limit the signal level before it gets all the way to the output, and it was my understanding that the damage occurs due to the actual output clipping. (if not, simple clipped digital audio could cause damage, too - can it?)

Just btw, this is the first time I've ever seen mention of clipping damaging headphones. I've only ever seen it mentioned for loudspeakers. IF (and I'm not sure about this) the damage occurs simply due to excessive energy going to the (loudspeaker) tweeter - i.e - exceeding the rated power of the tweeter, then for headphones, being a single "entity", with a single power rating, can't we now state with high certainty that the CA48 can't damage the SHP9500? (playing solo piano at least - not going crazy with audio inputs etc etc, which we haven't tested)
I know we can't guarantee it, but the volume is nearly at 100%, and it's not crazy loud. (2.5V RMS would be extremely loud)

Greg

If this page is correct, then it's very simple - clipping causes more high frequency energy to be present in the signal, which may then overload the tweeter.
https://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/clipping/page1.html
(and yes, in theory, this does mean that clipped digital content could cause damage)

Again - we have the power rating spec for the SHP9500, which allows a very loud sound level - I calculate 124dB. I don't think the CA48 is coming close to that, so even if it did clip, I don't think any damage would occur.

Greg

Forgot to reply to this. So far, I see no evidence of a defect in the piano, or that the headphones are inefficient. If the headphones were inefficient, they would not go loud enough with the smartphone. I saw no complaint of this - they were tried with the phone.

At the moment, I'm of the opinion that the CA48 has a rather low signal level (like a smartphone), but unfortunately, has a somewhat high output impedance as well. And let's remember - a sufficient volume level *can* be obtained! This idea that the volume control should not be near 100% has to be abolished ASAP.

Greg

As a recovering audiophile I don't see the underlying electronic basis for this claim. Pianos are capable of a huge dynamic range, and their peak sound pressure is far higher than the average sound pressure during a given piece of music. Unless an amp is purposely limited in its maximum input voltage--say by ensuring that 100% on the volume control is nowhere near driving the amp to its maximum rated output--it is capable of clipping. But amps running near their rated output also can distort in a more pleasing way than clipping from 'running out of gas' when hit by peaks--the dynamic range of what you hear then is reduced.

That's exactly what I think an instrument like this - a home DP, would do, as I said earlier - prevent the signal level (and gain setting) of the headphone amp from clipping, at least under most normal usage situations.

They allow the volume control to go to 100% because that's as much as it can safely go to.

And again, even if I'm wrong about that, given that the OP is not getting extremely loud levels out of the SHP9500 with the volume near 100%, and given that the SHP9500 is *capable* of producing extremely loud levels (124dB), that means that the CA48 is unlikely to have the capability of damaging the SHP9500.

So, if I'm wrong, and the CA48 can, in fact, clip under normal circumstances, the user simply has to reduce the volume until the clipping goes away, and decide whether that lower volume is sufficient or not.

Greg.

Agreed. I have never come across a DP internal headphone amp that appeared to have the potential to harm any but perhaps sensitive in-ear phones. In contrast, my most-used external headphone amp can put out over 3 W per channel at 30 ohms and 320 mW at 300 ohms. It could fry a lot of headphones even without clipping...

3W - wow! Proper respect

Just btw, I'm reminded of my Kurzweil PX1000. (going back a bit)
It would go to extreme lengths to avoid digital clipping, by restricting the volumes of notes, as they are played - it applied some type of dynamic range compression, or modified the envelopes. No way in the world were they going to let it clip, but the sound was altered quite drastically.

Greg