DT990 Pro Without Amp

[akki007]

How do the DT990 Pro's (250ohm) perform unamped? Or perhaps more specifically, using the HD30GB9? Anybody tried this combo? I can amp them if required but I like the portability of DAP and cans without the amp.

 

[boomana]

Quote:

Originally Posted by akki007 /img/forum/go_quote.gif How do the DT990 Pro's (250ohm) perform unamped? Or perhaps more specifically, using the HD30GB9? Anybody tried this combo? I can amp them if required but I like the portability of DAP and cans without the amp.

250 ohm = get amp now

 

[hardstyler]

I just tried 990pro with Iriver X20 and the sound isn't that bad (it can be much better of course) but there is simply not enough volume.

 

[akki007]

thanks guys! I was hoping the amp in the HD30GB9 may be sufficient to drive them?

 

[Shahrose]

HD 30GB9? can you tell us what that is. sounds like an mp3 player.

i know the 990s sound excellent out of a good soundcard out, but i noticed an amp helped give a lot more volume and tightened up the bass, and improved the soundstage.

although my dt990s 250ohm sound pretty good out of the cowon d2, but it struggles to give it enough volume. and the bass doesn't go as deep. soundstage is a bit closed in relatively. but overall, they sound good out of the cowon too.

 

[akki007]

Quote:

Originally Posted by Shahrose /img/forum/go_quote.gif HD 30GB9? can you tell us what that is. sounds like an mp3 player. i know the 990s sound excellent out of a good soundcard out, but i noticed an amp helped give a lot more volume and tightened up the bass, and improved the soundstage. although my dt990s 250ohm sound pretty good out of the cowon d2, but it struggles to give it enough volume. and the bass doesn't go as deep. soundstage is a bit closed in relatively. but overall, they sound good out of the cowon too.

Sure, apologies...HD30GB9 is a Kenwood DAP with a built in amp...

Kenwood HD30GB9

 

[facelvega]

You're willing to carry around a giant pair of Beyers but not a little portable amp? If audiocubes' spec listings are right, the Kenwood's output is rated at 6mW per channel into 16 ohms, and that would mean far less into your high-impedance Beyers. For comparison, a Cowon iaudio 7 is rated at 26mW, and it still wouldn't be enough to drive the Beyers respectably. Now, I notice little dot lists amp output into various impedances, and their relatively cheap MkI portable will do 500mW into 32 ohms, 150 in 120 ohms, 60 into 300 ohms, and 30 into 600.

 

[ericj]

If you do the math on the kenwood's 6mw into 16 ohms, it points to an output voltage of about 1 volt rms.

I don't think it can directly drive anything but very sensitive low-Z earbuds. And even then it's probably not performing very well and will likely go into clipping very quickly.

Owning a good DAP and a good pocket amp, I understand the consternation it causes. What am i supposed to do, keep them in one big pocket so they can knock around? Keep them in separate pockets with a cable running between them? DAP on my belt and amp in pocket? Figure out some sort of two-pouch belt-mounting system? Buy a fannypack?!

Sad but true - if you want the awesome headphones to come with you on your walk, you've got to bring an amp. Somehow.

 

[facelvega]

I wonder if the audiocubes thing is just a typo, though, as those Kenwood players are supposed to have decent amp sections. But even if it was supposed to be 36, more than any other current production dap I know, the point would still be the same in relation to a portable amp.

 

[ericj]

Some other websites say 8mw into 16 ohms, which upgrades it to a whopping 1.1 volts RMS.

Kenwood also sells a version of this DAP with a gold plated interior frame and claims that because there's 13 cents worth of gold flash adjascent to the circuits that make the music that it sounds better, so, kenwood's credibility is Very Low for me.

 

[akki007]

Ok, so my next question is... Will my PA2V2 headphone amp power the DT990's? I suspect it will.

 

[ericj]

Probably. Are they 250-ohm or 600-ohm?
Edit: NM, i see you said 250-ohm. Yeah, the pa2v2 is probably fine, though i've never personally heard that amp.

 

[facelvega]

yeah, should be fine. In general with headphones, there are two amping issues: first, sufficient power to drive the headphones well at all, and then second, the small differences that make one amp better than another. The pa2v2 tends to score low on the second category, but it'll probably get you in the door for category one, which is much more important.

 

[akki007]

I think I will replace the PA2V2 with something else, perhaps the Minibox-E as it looks really small. Any thoughts?

 

[holland]

Quote:

Originally Posted by akki007 /img/forum/go_quote.gif Ok, so my next question is... Will my PA2V2 headphone amp power the DT990's? I suspect it will.

No. 3V source (or 2.4V source actually) is not enough.

The PA2V2 may seem OK, but if you do the math you'll find that it will clip even with very low gain. You can't even get max range with 1Vrms. It simply does not have the voltage to cleanly amplify music with high dynamic range (movies, orchestral pieces, etc.).

I would recommend a minimum of 9V, better with 18V.