Best $500 Tube amp for K702

I can recommend the X-Can V8P with confidence. I used it with my K701's and was extremely happy with it. Just today I received a Woo WA6SE, and while I do prefer the Woo, the difference is extremely slight. It took quite a bit of critical listening to find aspects of the Woo that were slighty better. I realized today just how amazing the X-Can is for the price. I still maintain it is one of the best values in the under $500 amp market. The soundstage is huge, excellent clarity, airyness, good bass, and crystal clear highs. No humm or hiss and enough power to push the K702's. I never got past 12:00 on the volume pot.
Shameless plug... my V8P is for sale at the moment in the buy/sell section..

I wouldn't recommend a $500 tube amp for the K-701. Reason being is that it has (IIRC) a 62 Ohm impedance.

Almost all inexpensive tube amps are OTL. OTL doesn't do well with lower impedance headphones, with just a few exceptions. The biggest one being the Zana Deux, but only because the 6C33C tube has exceptionally low output impedance. That's what makes it so special.

Most OTL amps will claim to drive lower impedance headphones, but you run into problems with the damping factor and excessive negative feedback to drive down impedance while also strangling (in my opinion) the sound. Further, I find the build quality of some inexpensive tube amps to be questionable. They cut all the corners just so they can sell the orange glow on the cheap.

The only way to get the output impedance nice and low short of a 6C33C (or a few others) is to use output transformers. Those generally aren't cheap. Not too long ago, I paid $500 to have a pair of Sowters shipped over from England. That's just the output transformers, not anything else in the amp. A good pair of output transformers will start around $200 and they just go up from there.

If you have to have an amp that glows, look at some of the hybrids. Those can have an acceptably low output impedance while still giving some tube flavor.

But if I were to keep it under $500, I'd go with a quality solid state amp. Solid state doesn't require a high voltage power supply, so you can get good quality at lower prices. Though tubes are all the rage (and I run lots of them), solid state offers great quality for the price. I think a lot of solid state amps sound terrific and wouldn't be that upset if rhey were all I had. A Gilmore Lite, EC/SS, M^3, CK2III, or a Beta22 would be easy to live with.

In case you bought the K701 brand new, check the back of the box and tells you maximum power input 200mw.

Now most of these enthusiast amps for some strange reason don't tell you exactly their output power, in simple terms, how many volts... Some that do tell you for example Canamp, which according to some here is the perfect match of K701, has an output of 5.48v (300mw at 100 ohms), and to convert that back to mw its 448mw! More than twice as much power recommended by AKG for K701. I'm sure that 450mw gives enough volume for K701 but at the same time its bound to left the noise floor and distort the frequency response due to excessive negative feedback...

The same applies to all of these 'enthusiast amps' that are designed to output a lot of power, which is great for high impedance headphones but not K701 and its very low power requirements.

So, if you want avoid the hassle of changing many amps, like a lot of people here who have owned K701, you need to find an amp, which at a particular setting outputs 200mw so that you give K701 the max it needs and nothing more or nothing less. Similarly an amp that is neutral sounding because K701 is extremely neutral and it won't tolerate any color (distortion).

I have fond the best synergy with K701 using the built-in amp of my Xonar STX, which is completely against any mob-mentality prevalent in this forum and i posted numbers as to why it works, check this thread.

http://www.head-fi.org/forums/f4/asu...ynergy-476602/

Current is something that people really have to pay attention to when it comes to low impedance headphones like the K701 (low impedance with relatively high current requirements).

If the Canamp for example outputs 300mW @ 100 ohms of resistance, then simple math (P/R = i^2) shows that the amp outputs roughly 54.772 mA of current for 100 ohms of load.

The AKG K701 receiving maximum power of 200mW @ 62 ohms resistance shows that it will require roughly 56.796 mA of current. The amp should be able to "technically" drive it assuming theres more power in the low end (no clue, never owned the amp)... which implies the current is higher than 54mA as you decrease the load... (which is already close enough to 56 mA anyways... in reality this amp should be able to drive it without getting all super close with the numbers)

OTL amps have a very hard time handling those types of low impedance phones, which is why hybrid/SS is the way to go unless as Erik said, you want to match impedance by using transformers...

I use the WA6 (older stock version without PDPS) with my K701 and I can vouch that it does sound great with plenty of detail and soundstage, but I've also heard SS amps at or below around that price range which do sound more dynamic and overall more efficient for K701 such as Shanling PH100 and Heed Canamp.

So WA6 IMO is a great choice for K701/2 IF you also have other headphones that can benefit from it... it's definitely a good jack (no pun intended ) of all trade type of amp. But if you need an amp just for the K701/2 alone, then overall it probably makes more sense to go with a SS amp at or below that price range.

The MAD Ear + HD sounds pretty good with 701s and is transformer coupled. You might be able to find a used one for that price.

One other option would be to look into the Hybrid designs. These offer some of the tube appeal and have the low output impedance and current abilities to handle most headphones..dB

My K701's have been paired up to my LiL Dot III+ since I bought the cans.... Have tried the 701s on SS amps also. But they are just fantastic sounding on the Lil Dot amp so there they stay.

I also have the dilemma of looking for a tube amp for my K702. I really like my K702 so I dont want to give it up but I also have a preference for the sound of tube amps. Currently I am interested in the Decware amp but it's a bit above what I can spend.

which output power setting of LiL Dot III are you using with K701?

there are a lot of good hybrid options at <$500. I would avoid cheap OTL amps for the k701/702.

I own the Darkvoice 336i (Fitz modded) and it makes the K702's sound wonderful. I am not sure if I am getting full bang for my buck with this amp, but it seems great!

I enjoyed my Elekit with my former K701. It's transformer coupled, which is a pro and it's nice warm and smooth if you get the 396 tubes. But if you like your music LOUD, it's a bad pick.