[Cankin]

I'm currently looking for an amp for my K701 and will be getting Proline750 later..
from what I've read, because they are low impedance, they need more current rather than voltage...
So my question is, Should I get a SS amp or Tube amp in order to provide them enough current?

 

[n_maher]

Unfortunately there is no simple answer to this question. It would entirely depend on the particular designs that you're looking at. Perhaps you could post a couple examples of amps that your considering for people to comment on?

 

[Cankin]

I'm looking at Darkvoice 336i, Little dot mkIII, Dared mp5, Headroom Micro amp, Gilmore Lite and maybe Canamp

does anyone know what is the retail price of Canamp?

 

[Frihed89]

SS and OTL

 

[phergus_25]

Well into the low ohm loads of your mentioned cans SS will
Unless you go with a output transformer coupled amp, in which case you can get some serious current
Then again a big set of caps on the output will also provide current, but that comes with its own set of troubles
Having said that I use an output transformerless amp with my W5000s, and will untill my custom amp gets here

 

[jcx]

how about anyone else here doing some numbers when this sort of question arises?

K701 62 Ohms, 105 dB/V

I consider being able to reach 120 dB SPL before clipping the amp to be "adequate"

this gives 5.6 Vrms, 90 mArms which needs another factor of 1.414 for peak values

128 mApk is a lot of current for a headphone, +/- 8Vpk isn't coming from a single 9V powered "CMOY"

SS - only recent surface mount op amp will do this alone, look for AD8397 or TPA6120

buffered op amp types with BFU634 or the HA series monolithics and most discrete buffer or all discrete ss amps should be able to do this with enough supply V (some single ended Class A discrete ss designs may not be biased heavily enough though )

Tubes are rather more hard pressed, transformers could do this if sized appropriatly but decent transformers add ~ $100 to the parts cost so you won't be seeing them in sub $500 amps

OTL tube amps would need to be biased at > 250mA and most would require parallel output tubes to reach this current level (there are a very few "monster" tubes like 6S33S which could do the job in singles)

you could get by with an amp not able to cleanly drive the K701 to to 120 dB if your musical taste runs to todays low dynamic range over-compressed crap

 

[Hi-Finthen]

I consider being able to reach 120 dB SPL before clipping the amp to be "adequate"......

Really?

Interesting wish list based upon objective numbers, however listening at anything over 100dbs with spikes included, simply isn't practical...

Unless the listener is deaf or chooses to be shortly,IMO...

 

[jcx]

Quote:

Originally Posted by jcx am I going to have to post this link every time I post? http://headwize.com/articles/hearing_art.htm read it twice, once for protecting your hearing, and again to appreciate just how much dynamic range you should want to be able to reproduce, even if only for seconds per hr of listening...

if you are happy with 105 dB peak clipping level feel free to recommend that the AKG K701 don't need no amp - just play from your iPod

Headroom that is rarely exercised and only for fractions of a minute is a distinguishing characteristic of higher rated amps, looking over the musical spl table again I might change the previous post to read that 120 dB clipping level is "barely adequate"

further when using SET or other "low feedback" amp the only way to lower distortion is to use the output device at a small fraction of the bias point