[GDunlop]

Hi,

I'm pretty new to the forum and I don't really know a lot about MP3 players and specifications.

I was wanting to know what specifications should I pay attention to if I am trying to determine how loud a device is when playing music. I am aware the earphones/headphones have an effect too but I'm really just wanting to know what particular specifications have the main effect on this.

Reason why I would like to know is that I have some quiet media files that can require a loud output to make the volume more acceptable.

At the moment I am using a Cowon Plenue D3. It's really good and is a player that gives a high output volume when needed. However since I don't really know much about music players it's difficult to compare it with others on the market since I don't really know what to look out for. Also just googling for this info doesn't yield much results.

 

[homesickmadmax]

I am not a specialist, but looking at the output power can certainly help.

For example, your player:

• Output power: 2 Vrms single-ended / 4 Vrms 2.5mm balanced

So if you want more power, maybe look this information first... But, it is not always what you will experience. My Sony NW-A55 has less power than my Hiby R3 but I still find them comparable.

It also depends on your headphones.

 

[GDunlop]

I am not a specialist, but looking at the output power can certainly help.

For example, your player:

• Output power: 2 Vrms single-ended / 4 Vrms 2.5mm balanced

So if you want more power, maybe look this information first... But, it is not always what you will experience. My Sony NW-A55 has less power than my Hiby R3 but I still find them comparable.

It also depends on your headphones.

Thank you for the response.

Looking around I see that a lot of others players show their power output as mW instead Vrms. I guess I need someone to explain if there is a way to compare these values.

 

[homesickmadmax]

Look, I found this website that does the calculation for the headphones you have:

https://www.audiobot9000.com/

 

[homesickmadmax]

I feel like this one is better:

https://www.headphonesty.com/headphone-power-calculator/

 

[megabigeye]

Yes, the spec that tells you how loud your amp/MP3 player can drive your headphones is power.
You can figure out how much power your headphones need for a given volume with a little math.

Two things/equations to know:
[1] In answer to your question above, yes voltage (Vrms) and power (mW) are related. Power is voltage multiplied by current, represented as P=V*I. Annoyingly, no amplifier manufacturers list current. Fortunately, current is voltage divided by impedance (I=V/R). So, power is P=V²/R, and voltage is V=√(P*R). This is called Ohm's Law.

[2]Adding +10dB of volume requires 10x power. So, if your headphones are 100dB @1mW, it takes 1mW to reach 100dB, 10mW for 110dB, and 100mW for 120dB. You can do this rough and quick on your fingers, or use: P=10^T-S/10, where P= necessary power, T= target volume, and S= headphone sensitivity.
So, if I want to listen at 90db with my HD 650 with sensitivity of 103dB @1mW, it would need P=10^{90dB-103dB/10} = 10^-1.3 = 0.05mW. From here you can figure out how much voltage and current is needed with Ohm's Law, above.

The tricky part for you is that your music is much quieter than the signals used for headphone and amp measurements. The math I've shown you will technically show you how much power your need to play your music at reasonable levels... If your music weren't recorded at such low levels. Your best bet is probably too increase the gain in your MP3 player, which you can usually find that with the EQ. I think Replay Gain will do it automatically so that all of your music is at about the same level, but I've never used it and can't vouch for it.

Anyway, I hope this was at least a little helpful!

 

[megabigeye]

My equation above is sightly wrong. The correct equation is:
P_T=10^(T-S)/10
P_T = target power, and you need to subtract T-S before dividing by 10. That was a little unclear in my previous post.

Oh, yeah. Also: this equation will give you milliwatts for power, but Ohm's Law uses watts only; any number in milliwatts needs to be divided by 1000. So, the 0.05mW for my HD 650 is 0.00005W, so to figure voltage (for example) you'd calculate V=√(0.00005W*300Ω).