[drgnclwk]

Hey everyone, I'm currently shopping around for a dac/amp combo preferably $200 or less.  I'll consider a something a little over budget if it's really worth paying extra.  I've been keeping an eye on e17 availability since I'm also looking for some portability, but I'm not sure if there are better alternatives I should be considering.
 
I'm currently using an ipod + e11 as my main listening source since I can't stand listening out of my laptop because I get an annoying crackle noise, most noticeable on music with vocals.  I don't get this when listening through my ipod so I'm assuming a dac is needed to fix this for when I'm using my laptop.
 
Furthermore, I notice some distortion when listening to my 600ohm akg k240 when maxing out volume on the ipod and e11 just to power it to my listening volume.  It does go away when I set the e11 eq down to 0 though.  I'm not sure if I just need a different amp to drive it better or if an lod will help with this but I'll probably pick one up soon to try it out.  Still need to finish restoring my k240 sextett though to see if I get the same problem.
 
edit: gear listed in profile

 

[H20Fidelity]

Just quickly. Are you running the E11 in high power mode? I found all sorts of distortion using the low power settings.

 

[drgnclwk]

Oh yeah, I always run the e11 set on the high power mode.  Personally, not worried about battery issues on the e11 either since the micca package came with a spare.

 

[dyl1dyl]

Try and stretch for a Nuforce HD, it'll be worth it. It'll make you go back to using your laptop as a source

 

[drgnclwk]

Thanks for the suggestion.  I'm taking a look at the nuforce and from what I see, please correct me if I'm wrong, it has to be powered through a plug adapter?
 
It looks interesting to use as a dac/amp for my laptop, but I'm leaning more towards something that can alternate as a portable amp if needed.  So if possible not needing a dedicated power source for on the go use as well would be great.  I'm just not sure if it's possible with my budget and the power needed to juice the k240 monitor & sextett.

I'm still trying to justify spending over the $150 it'd be for an e17, whether or not the cost to performance ratio would be worth it.

On a side note, plugged into the laptop for music and the first thing that came to mind was it sounds 'dirty'.  Immediately switch back to ipod+e11.

 

[uku383]

You might want to look at the Leckerton UHA-4, which is a portable amp/DAC. Nick is very good at responding to enquiries and although he's out of stock this shouldn't be the case in the next week or so.
 
I only mention this as I'm in a similar boat to you and after a bit of digging around the Leckerton was my choice. It's got good reviews on the boards.
 
Here's a link to the Leckerton site:  http://www.leckertonaudio.com/products/uha-4/
 
Have fun shopping!  

 

[drgnclwk]

Thanks for the suggestion, I feel like I may have read some of that thread.  The only problem is that I'm not sure how well it would be able to drive the k240 monitor & sextett.  If I remember right, there were some posts in a review thread for the leckerton mentioning that it doesn't power 600 ohm headphones so well.
 
Most of the tech specs on amps are too foreign for me to interpret and identify what I need so I can't say for sure if this is the case or not.

 

[PurpleAngel]

Quote:

Hey everyone, I'm currently shopping around for a dac/amp combo preferably $200 or less.  I'll consider a something a little over budget if it's really worth paying extra.  I've been keeping an eye on E17 availability since I'm also looking for some portability, but I'm not sure if there are better alternatives I should be considering.
I'm currently using an iPod + E11 as my main listening source since I can't stand listening out of my laptop because I get an annoying crackle noise, most noticeable on music with vocals.  I don't get this when listening through my iPod so I'm assuming a DAC is needed to fix this for when I'm using my laptop.
Furthermore, I notice some distortion when listening to my 600ohm AKG k240 when maxing out volume on the iPod and e11 just to power it to my listening volume.  It does go away when I set the e11 eq down to 0 though.  I'm not sure if I just need a different amp to drive it better or if an LOD will help with this but I'll probably pick one up soon to try it out.  Still need to finish restoring my k240 Sextett though to see if I get the same problem.

Restoring AKG K240 Sextett 600-Ohm headphones?
I just got some used AKG K240M Monitor 600-Ohm yesterday (only $65 off eBay).
You can get the DAC Destroyer off eBay for $40, what a name for a DAC.
 
 

 

[mikeaj]

The 600 ohms vintage AKG K240 models need a LOT of voltage (for a given volume), more than 600 ohms Beyerdynamics.  E17 is not powerful enough.  You want something in the 8-10V rms output range, ideally, though maybe a little less than that is okay, depending on how much louder you think it could stand to be.  You're probably driving the E11 into clipping with a high enough bass boost EQ and high enough output.
 
E9 and Asus Xonar Essence ST/STX go to 7V according to tests, E11 goes to about 2.7V according to tests, Leckerton UHA-4 goes to 2.1V by their spec, for reference.  FiiO's spec, which is sometimes optimistic, is 3V output for the E17.  Anything that's USB powered is not suitable.
 
I would suggest a cheap USB DAC and then a relatively powerful amp like maybe an E9 if you must stay within budget, not like most cheaper amps a little above budget can really do 10V rms (28V peak-to-peak) output.  If you want an all-in-one unit for whatever reason, maybe the Audinst HUD-MX1?  I can't vouch for their quality and can't find any real specs on that though.  
 
Honestly, the marketing makes it look sketchy, but that's just a guess by me.  edit: on second thought I'd like to re-emphasize that this is just a guess.  The rationale is just that it seems that the more companies advertise what specific components are inside their device, the less good they tend to be.  Of course this is just a correlation.
 
I wonder how some cheap class D speaker amp modules would do?

 

[Cassadian]

Again... this is a portable amp forum.  Therefore I foremost will not recommend any desktop amplifiers and only recommend a 200 dollar DAC/AMP such as the iBasso D7 ,  iBasso D4 Mamba, or the Leckerton UHA-4.

 

[uku383]

Quote:

Thanks for the suggestion, I feel like I may have read some of that thread.  The only problem is that I'm not sure how well it would be able to drive the k240 monitor & sextett.  If I remember right, there were some posts in a review thread for the leckerton mentioning that it doesn't power 600 ohm headphones so well.
 
Most of the tech specs on amps are too foreign for me to interpret and identify what I need so I can't say for sure if this is the case or not.

I asked Nick a similar question. He replied: "The amp can drive anything from low-impedance in-ears to high-impedance cans. I've even tried it with 600 ohm headphones, and  
it gives a decent output level. I think Headroom.com has some great reviews on a wide variety of headphones, so that might be a good place to check."
 

 

[drgnclwk]

Thanks for all the input, I'll look into these once I'm off work.
Although portable is preferred, if it isn't really a viable option I'd entertain some semi-portable options as well. Something like the nuforce hd seems like it'd still be a good size. I'm avoiding anything big and not as easily transportable at the moment such as the schiit products.

Yeah I'm still in the process of restoring the sextetts I picked up recently. It mainly needed old foam to be cleaned out and elastics replaced which the rep from akg was kind enough to give to me. Also need to shorten the wire a bit since part of it is exposed and a bit frayed. I was lucky enough to pick up a pair of k240 monitors new in box so it was in great condition as well.

 

[drgnclwk]

Since my main concerns are having a dac and driving the two 600ohm akgs, I'm looking at several options right now.
 
So far it seems like a used nuforce hd would be a solid choice.
 
Also briefly read a bit on the audinst hud mx1 which doesn't seem like a bad choice either at $180 new.
 
Saw mention of the nfb-12.1 which might be an option, but I don't know what all the switches do yet since I only glanced at the product site so far.
 
Alternatively, for a lower price point a e7+e9 combo looks like it'd be a decent  and most affordable setup.  Especially since it sounds like the e17 won't be able to stand on its own for driving my k240's.  However, I'm also debating going with the e17+e9 route so I'd have the e17 dac/amp on the run yet the power of the e9 at home.  Even then the e9 is compact enough for easy transportation.  The headfonia review makes me question using the e17+e9 combo though.
 
As for the leckerton uha-4, I'm still more worried that it would lack the power to properly drive the 600ohm k240's like the e7, e11 and e17.
 
Now I just have to decide between all of these, but I don't know where to go from here yet.  More input would be greatly appreciated.
 
edit: Looking at the ibasso d4 and d7, I'm not sure where to look for output power and how it would handle the 600ohm k240's.
Definitely not expecting the best with my budget, but these all seem like decent options.

 

[mikeaj]

Quote:

edit: Looking at the ibasso d4 and d7, I'm not sure where to look for output power and how it would handle the 600ohm k240's.
Definitely not expecting the best with my budget, but these all seem like decent options.

I didn't look very hard, but I didn't see too much explicit specs either.  Maybe they think consumers don't care or are bothered by seeing numbers?
 
Anyway, they mention the D7 as having an amp that runs off +- 5V supply rails.  Because of the way electronics work, the output's not going to be able to exceed either supply rail, so it's not going to have 10V peak-to-peak output (maybe less like 9V, 8V), which would be 10 / sqrt(2) / 2 = 3.5V rms at most.  Depending on the true amount, that's around the same as the E11.
 
For the D4 the manual says 230 mW into 32 ohms.  P = V^2 / Z so V = sqrt(P * Z) = sqrt(0.230 * 32) = 2.7 volts (rms).  Possibly it could be a little higher into higher impedance loads, but I'd be surprised since it either runs off USB power or a single +9V battery.  2.7V rms seems like a usual drive limit of a device running on 0V / 9V power.  It would be possible to use the battery or USB power with DC/DC conversion or charge pump to create a negative rail or higher supply rails, but that seems farfetched considering the single +9V battery runtime listed at 9 hours, the size, and the cost.  This is probably around the same as the E11.
 
 
Again, all this depends on how loud you want to listen.  For many people on lots of music, maybe an output in the range of 2V is enough.  A low-powered device can easily drive 600 ohms headphones and sound good, just maybe not loudly.  That's why I'm giving the E11 (around 2.7V max) as a reference.
 
 
So the reality is that these are some of the least sensitive, high impedance headphones in the modern era, so they need more voltage than anything except like maybe HE-6 and then oddballs like electrostatics, AKG K1000 earspeakers, etc.  I mean, it just doesn't make sense for portable device manufacturers to design a device just so they will handle vintage discontinued AKG K240 models, which are a fringe case.  You need high supply rails to enable a high output, and the high supply rails (not necessary for the vast majority of other headphones one could be using) would increase the size, weight, and price, while making the thing hotter and reducing battery life--well maybe not all those things simultaneously, but you get the point.  It's like lose-lose-lose-lose-lose-win, so nobody does it.