[tvhead]

I brought in my V6s to the apple store for an iPod listen. Feels like I have to put the volume to about 3/4 max to get it to a good level. With my 20mw PCDP I just set it to about 1/3 max to get it about the same level. What's the big idea?

 

[utdeep]

Its called Marketing. I wonder if some of their other numbers are correct as well... compaq told me their iPaq would last ten hours per charge as well.

 

[tvhead]

Apple claims it's supposed to last about 10 hours. Some reviewers I've read say it actually lasts about 12 hours. They also say it can hold 1000 songs, not a 1000 128kbs 3 minute songs, but 1000 160 kbs 4 minutes songs.. I always felt that apple was conservative with what they claim. I was hoping the same would apply with the amp section..

 

[chych]

I'm willing to bet that Apple simply let the impedance rating on that headphone output slip by... watch it be 30mW x2 at 8 ohms or something...

 

[tvhead]

I feel ripped off. Isn't there some kind of standard that people have to follow?

Or could it be listing the peak power like little car stereo head units have 80watts per channel?

 

[Xevion]

I think cych is right - they could have specced the output to 8 ohms, if it does 30mW at 8ohms it does 7.5mw at 32ohms. Barely more then a portable CD.

 

[lextek]

Yeah. I'm not to sure on the ouput spec. to drive Sennheisser MX-500's I need to turn it up quite away. It's sounds great, just have to turn it up. When I have it hooked up to my Creek OBH-11 with iPod volum a little nore than half way I need to turn the Creek to about twelve oclock postion w ith HD 600's. I still love though.

Bob

 

[Neruda]

my guess is that the iPod has 30mW into 16 ohms while the CDP has 20mW at 32 ohms. Still, it isn't impossible that they used 8 ohms or something. If you want power, you can get the PJB which sucks in almost every way compared to the iPod (

) but has 50mW per channel into 32 ohms; or you can use a headphone amp. I'd go for the latter.

 

[lextek]

I would'nt get to wrapped up in the numbers. I t sounds good. Sounds even better with an Airhead.

Bob

 

[MacDEF]

Quote:

I feel ripped off. Isn't there some kind of standard that people have to follow?

tvhead, you've never shopped for an amp before, have you?

Power ratings are simply marketing -- there is no accepted standard in the audio industry.


That said, one of two things could be happening with the iPod:

1) The impedance isn't listed (as other mentioned)

or

2) The gain on the volume control is end-loaded. In other words, over the first 2/3-3/4 the volume doesn't change a lot, but over the last 1/3-1/4 a little increase in volume setting increases the volume quite a bit. Some amps do this so that they can be used with both sensitive and non-sensitive speakers/headphones. If you've ever used a pair of efficient headphones with a front-loaded gain, you know how frustrating it is to find a volume that doesn't damage your eardrums.

What happens when you turn the volume past the "normal listening level?" Does it get very loud quickly?

 

[tvhead]

The max volume on the iPod was no big deal. Louder but tolerable. It wasn't going blow out my headphones. There was no exponential growth as I got closer to the max. My PCDP on the other hand, I'm kind of afraid to get it even above 1/2 max with my V6s.

BTW, the reason I wondered about the standardizations of wattage for the headphone amp was because they never list the impedance with the wpc like they do with amps for speakers. My PCDP lists its power as 20mwpc. I see nothing about what its impedance is. Other pcdp list theirs at 9mwpc with no mention of impedance. iPod same thing. This, I assumed, was a standard for measurement of headphone amps; all using the same impedance to give that measurement. Most of you, I think, assumed the same thing. I don't remember any of you saying, "30 mwpc? yeah, probably into 8 ohms," before I said anything about this. It was more like, "Wow, this is great, somebody is making a portable with some decent power like the old days." Even when a reviewer said that it had 6.5mwpc, you said they had no idea what they were talking about and that it was in fact 30mwpc.

Lextek: The reason I feel cheated is because I don't want to use it with an airhead. I don't even want to use it with a cmoy amp. Basically you're doubling the size and weight of the iPod. Wasn't the number one objective according to Mr. Jobs is to make it ultra portable? It's only going to super portable then..

 

[chadbang]

Well said Lextex,but I venture to guess the general public will never get beyond the earbuds that come with the unit. And if those earbuds can be driven well by the ipod, then Job was true to his word (if not the @#$%*! specs!)

 

[blr]

Agree with MacDef on the power rating issue. No one knows how these measurements were done and how much marketing is involved. I'd love to see some independant measurements.
It is the same thing with speaker amps. Even in the HiFi press people often notice that some amps are severely overspecified.
I ran into the same thing with my new CDP. The Sony D-EJ725 is specified at 5 mW into 16 ohms, which looks mediocre on paper, but it still plays louder than my MDP (Sharp MT866) which claims 5 mW into 32 ohms. Looks like Sony has more conservative (honest?) rating.

 

[lextek]

I only was using the Airhead or Creek while sitting at home. I use as a second system with HD 600's. When I'm out and about I use the Sen MX-500's. I find that set-up great. Maybe I don't listen at the higher volume levels of some folks. Still sounds good.

Bob

 

[tvhead]

blr,

My point is that if you guys knew there wasn't a standard, there would have been second guesses about the the 30mwpc from the get go. It was in fact the exact opposite! As I said, one reviewer stated the iPod had 6.5mwpc, you guys' conclusion was that he/she didn't do their homework. If you guys really felt there wasn't a standard, then this review should have automatically prompted you to think that maybe just maybe apple rated the amp at 8 ohms, but it didn't!! We all fell for the 30mwpc claim just like I did. What irks me is that you guys are acting like you knew all about it.

My Rotel integrated amp is rated at 35wpc at 8 ohms. It's not much but it plays way louder than I'll ever set it at, and it'll play just as loud and without the strain as those Kenwoods listed as 100wpc. I think I read in some magazines that this is due to higher current. What the heck does that mean?