[SinnerG]

I am using a C&C XO amp which is rated for 1000mW per channel, and running a low-ish impedance set of 52 or 54mm drivers in the ATH-A900 headphones. I run the knob on around 1/4 turn.

I'm looking for another portable amp now.

Thing is, what's the deal with these super-expensive units out there that don't output more power than a soundcard or even an ipod? I'm looking at some interesting ones out there have a mere 30mW output and then there are some others which do 300mW.

I have a Asus U1 USB soundcard which outputs around 70mW and it is plenty loud, but "untidy".

The ipod shuffle is on max out to even get to a level I feel comfortable with.

How much importance do you fellow head-fiers put into the output rating of an amp along with the other specifics? Or do people not care about this rating and are simply fine running it all on a max volume setting to get them to drive large cans?

 

[billybob_jcv]

It's a balancing act - IMHO it's not really the same as sizing an amp for a speaker set-up - it's not just about watts/channel. The efficiency and impedance of headphones has a huge effect on the requirements of the amp, and so does the level of the source signal. I think that's why headphone amps are often sold based on the gain, not the output wattage. A gain of 2 will work pretty well for most high-efficiency, low-impedance IEMs, but low-efficiency, high-impedance cans probably need a much higher gain from the typical ipod - perhaps as much as 10 or 11 for the most hungry. Putting a high gain amp on IEMs may cause clipping, distortion and/or hiss, and putting a low-gain amp on hungry cans may leave them wanting for more. I guess the bottom line is that it's all about the total system - source media, DAP, amp & cans - if they all mesh well, you're golden - but if they don't (in either direction), you may not be happy with the result.

 

[SinnerG]

Thanks!

That makes sense to me, especially the gain part. Problem is finding that combination that works correctly as that could get expensive not being able to hook up and test beforehand.

I suppose best bet for me then is to look at the amp I use now and try and find something with similar gain values, perhaps with a low/mid/hi type of offering and not bother too much with the power output.

 

[ddoingwell]

As a career professional musician, former studio owner and one-time tech in a hearing aid clinic doing audio-metric testing I can tell you this: ALWAYS listen to your music at a volume just slightly below what you might really like and avoid distortion like the plaque. Sound Pressure Levels in headphones are very, very dangerous and some of the new amps that rock your head are making large steps towards ending your ability to hear. Ear fatigue (the ability to discern volume and detail) happens within 15 minutes of exposure to excessive SPL. Walk along a busy highway for 15 minutes and part of your hearing is already muted down...not damaged, but shut down temporarily. Do it too much and you're asking for trouble. Tinnitus, or ringing in the ear indicates permanent damage. This is serious stuff kids; we LOVE our music or we wouldn't be involved in these pursuits. Moderate your volumes, buy the BEST source and gear you can afford and protect your hearing around all motors, amplified music in clubs, lawn mowers ect. Same with any sound source. Dentists almost always have hearing loss at 8K; same with electric guitar players. It's the high frequencies that do the damage and that is where hearing loss occurs first. Bassheads in closed cars with thunderboxes in the back seat will be deaf long before middle-age.

I have this little rant in my head every now and then and it amazes me that some of the older head-fi types haven't raised this as an industry concern before. Good clean sound at or below comfort levels, not concert levels, will not damage your ears. Buy the best gear you can afford and get ear plugs for those horrible moments when the world gets too loud. You'll be glad you did and everything, I mean EVERYTHING will continue to sound fabulous for a long long time.

There: I've said it. And yes, I'm too old and sure, it's too loud.

God Bless
Don

 

[aamefford]

Props, Don! I couldn't agree more - Cheers from a 49 year old ex-light man with enough sense to wear earplugs, and enough hearing left to enjoy my headphones!

 

[ddoingwell]

Quote:

Originally Posted by aamefford /img/forum/go_quote.gif Props, Don! I couldn't agree more - Cheers from a 49 year old ex-light man with enough sense to wear earplugs, and enough hearing left to enjoy my headphones!

Thank you; I'm glad to have a seconding voice of reason. I'm going to copy what I've written above and start a thread. Maybe some good will come of it.

Merry Christmas to all
Don

 

[SinnerG]

I hear you (pun intended) on all of this. I was just trying to figure out what the deal was with all those power ratings, etc. I can't do the C&C XO beyond 1/4 turn. I run it where I enjoy what I hear and not where my head feels like imploding. I'm actually looking to find out what sort of powering amps should have so that the volume knob was more controllable. I don't like running things on max all the time. My wife's little ipod shuffle has to run at max for the sound to be comfortable and me not straining to hear stuff, but I don't run earphones or IEMs so they probably work loads better there compared to a pair of fullsized cans.

As for those kids in their cars... sorry, mate, they are deaf already if they have to run the stuff that loud.

As for tinitus... don't preach to me on that 'cos it's way too late. Mentioned it in another thread already, but damage was literally done in a single night back in 1994.

So, yeah, finding the proper source is the deal here, not blasting my ears off just because I asked what the deal was the power ratings on portable amps.

 

[scompton]

I think the portable amps you're seeing with low output voltage are designed to work with low impedance, highly sensitive IEMs. This is not true with a lot of portable amps. People seem to have a need to amp IEMs like the UM1 instead of plugging into their player's headphone jack. I actually fell in to that when I started out here. I bought 3 portable amps before giving up. All three went from no sound to too loud with nothing in between. They can all easily drive my 600 ohm AKG K240 Sextetts.

I think most people who buy amps to drive most IEMs and lower end ATs and Grados, are probably listening way too loud. I don't know the C&C XO but I never turned the volume past 9 o'clock with my XM4, even with the Sextetts. You may be listening too loud.

 

[SinnerG]

Just because I own a pair of ATs and an amp doesn't mean I'm listening too loud. The amp gives off a much better sound that my source's output does. I literally do not have to fiddle with the equalizer at all compared to when I was just using the soundcard. It's awesome stuff!

I was looking for another amp instead of the XO, but in my 'net travels I started seeing all these varying output levels. That's why I started this thread to ask what the deal is and what I should be looking out for.

The XO is nice, but at a very quiet setting the left comes on earlier than the right so I have to take it up a bit. 1/4 is my sweet spot for enjoyment and that's not loud at all. Take it past 1/4 and things get ugly loud.

Your mention of driving IEMs is possibly what I've overlooked. I don't care much for IEMs so I completely didn't figure that into it all as I'm a full-size can user.

I'm sure even low impedance full-sized headphones will need a bit more juice to push back and forth compared to an IEM, albeit dependent on things like the sensitivity of the driver, etc.

I think best for me to pay more attention to the internals of the amp, what people say about what it does to the incoming sound signal (again, a very subjective thing), rather than wondering what the deal is with these power output ratings. Billybob_jcv mentioned looking into the gain settings instead, but when I look at amps I had in mind I just don't see any of that information available.

And can we stop the judging on listening too loud?

It's a subjective thing, each person is different.

 

[Sherwood]

Quote:

Originally Posted by SinnerG /img/forum/go_quote.gif How much power does one need?

Moar power, of course.

What one does not need is more volume.

 

[SinnerG]

Nice.