How should I improve sound quality for Sennheiser HD 600 without spending a lot of money?

well you could try too get a better cable, or a new amp/tube amp? A better dac will make it sound better but I would not worry about that until you are looking at some hd800s or t1s
 

I haven't found the HD600s to be hard to power or really benefit from a better sounding source. The HD600s and 650s are kinda veiled in that they aren't as resolving as a DT880 or HD800 which I personally considered an upgrade, the Senns are very smooth.

Mod a pair of T50rp's, given the time, it will satisfy.

The better AMPs/DAC like Yulong D100, Mini i+Matrix M Stage, Nuforce HDP will improve the soundquality, i listened HD600 with higherend DAC/AMPs and they are superb mids focused sounding headphones(works great for Rock, Indie, Instrumental pop, Jazz).

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Originally Posted by TheChosen0ne 

Need more opinions on which amp/dac I should get but don't cost an arm and leg

What is your budget?

My $0.02, from an HD650 perspective: Upgrade the amp first.   Preferably tube/hybrid, but SS will do if that's what you prefer.  That's the first major upgrade.  DAC & transport second.  Make sure you're streaming good quality audio over a good interface to a good DAC.  The DAC is what gives you your fine detail resolution, and HD6xx can resolve quite a bit of detail.  Once you have amp & DAC taken care of, and have decent cabling between then (BJC will do well, Monoprice's premium is good in a pinch if you don't mind highly sitff cabling.)   After both of those are taken care of (and assuming good music sources: lossless, etc.) then the final jump is the headphone cable.  It's the worst value for the money proposition of the three.  The performance shift is slight, can only be revealed if the source gear is good enough, and costs a lot of money for the shift.  But it's the final touch on an already good setup.

Your headphones can scale a long way.  The amp can be a major improvement.  The DAC will seem like a minor improvement, but can be significant and recording dependent.  The cable is fine tuning, but if everything else is in good shape can be the difference between "wow" and "WOW".

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Originally Posted by SONIC BOOM 

well you could try too get a better cable, or a new amp/tube amp? A better dac will make it sound better but I would not worry about that until you are looking at some hd800s or t1s
 

I would...  HD600 & HD650 are legendary for their ability to scale with better gear.  There's no less reason to worry about your gear with HD6xx than HD8xx, except that HD800x may scale even beyond into the truly esoteric stuff.

Try this: http://apuresound.com/hdsennmod.html

I found my sennheisers to be noticeably better after that. Better bass impact, less veil over the whole sound, and sound stage seemed to have opened up. 

Quote:

Originally Posted by TheChosen0ne 

I've bought the HD600s with Fiio e17+e9 which is my first high quality headphones about 5 months ago and im super happy with the sound quality but just curious what amp/dac is better and what are the other stuff I should change to get better sound quality but don't cost a fortune to get?  Last week I got the iPhone 4s which is my first smart phone.  I used the iPod touch before this.  Just for fun I used the earphone that it came with the iPhone and it reminded me how crappy those earphones were.  I couldn't believe I once thought that I didn't need to get any other earphone/headphone because I was satisfied with those damn apple earphones! 

I'm going to guess you can not improve the sound much without spending at least $300 (or more) for a DAC and Amp.

For a DAC, the SMSL AD-1955 DAC sold on eBay.

For an (tube) Amp. The little Dot II MKII or a Little Dot MKIII

So $270 to $330 total.

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Originally Posted by plusSound 

I would suggest an amp or/and a cable which will enhance the sound of your headphones.

+1 here. Depending on how much you want to spend, you can get a nice OTL amp for them (I recommend the Bottlehead Crack), or get an HD650 cable. Heck, I braided a cable for my HD600 out of some Mogami and it turned out awesome, sounded great too!

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Originally Posted by mosshorn 

+1 here. Depending on how much you want to spend, you can get a nice OTL amp for them (I recommend the Bottlehead Crack), or get an HD650 cable. Heck, I braided a cable for my HD600 out of some Mogami and it turned out awesome, sounded great too!

The HD650 cable is a nice upgrade from the HD600 cable.  Not sure if the OP believes in cables but there is a subtle increase bass punch in the HD650 cable.  If you don't believe in cables, at least the HD650 is sturdier and looks better =)

I would personalty get an other headphone to see, if they don't match better my taste, or at least something that beats the  hd600 on a particular kind of music (example: techno) . And once you've experimented a lot, you might just get a high end headphone that match your tastes.