[russelkhan]

I'm thinking about buying an Earmax Pro for my Sennheiser HD600. I have no experience of tube-based amps and I was wondering how long these tubes last, how easy it is to find replacements, and how expensive they are.

Are there any other issues that I should be aware of? I've heard that tubes tend to sound very smooth - does this mean that the sound is less detailed and not suited to rock music?

Any feedback would be greatly appreciated.

Cheers.

[alexs2]

The tubes last usually for several years at normal levels of usage,given that they're robust,small signal tubes and not like power tubes as such.

In buying an Earmax Pro,you will find that the UK importer is somewhat secretive about the exact types of tubes used,and "prefers" that you get replacement tubes from him when the time comes.
I've got the types of tubes used at home somewhere,and AFAIK,the Earmax Pro uses an ECC81 as the input/driver,and 2x ECC88 as the outputs.

These are readily available tubes,and the best by far are Mullards and old Telefunkens.

[Paul Williams]

Originally Posted by russelkhan

I'm thinking about buying an Earmax Pro for my Sennheiser HD600. I have no experience of tube-based amps and I was wondering how long these tubes last, how easy it is to find replacements, and how expensive they are.

Are there any other issues that I should be aware of? I've heard that tubes tend to sound very smooth - does this mean that the sound is less detailed and not suited to rock music?

Any feedback would be greatly appreciated.

Cheers.

I can't answer on the basis of the Earmax specifically, but for valves in general, one of the real benefits (or not if you don't want to spend money) is the ability to change the valves, all of which have their own sonic signature. To an extent you can tailor the sound of a valve based product. A lot of people, when they initially hear valve based product feel they are missing something, but in reality its all there and what they get is a more musically coherent presentation without fatigue and personally, price for price, I've always found valve amps to give more detail than most solid state counterparts. But just like SState stuff you can get products which sound poor - the Earmax given its price, seems to have a solid following, which would suggest a good all round performance.

Tube life can be viewed as a downside, but the Earmax amps only have small signal valves and I'd expect that these would be good for at least 4 to 5 thousand hours. This equates to at least 4 years if you listen for 4 hours a day, 5 days a week for 50 weeks in a year. Of course if you have a duff valve.......
As for cost £5 to £500 per tube? Then again in 25 years of using valve gear I've only ever 'had' to replace 2 valves and one of those was a 50 year old used one I bought from eBay - and that lasted 2 years of really heavy use.

Paul

[russelkhan]

Thanks for the replies

[Nic Rhodes]

These tubes are generally run, not 'too stressed' either, which means life is long. For current Russian / Chinese production, they should be a good few thousand hrs (which is many hours of listening!). Old Mullards should manage 10,000 hrs with no trouble and some variants much longer (M8***). Old Telefunken have been known to do 100,000hrs!!

Re the importers, secretive attitude to the 'headphone' valves, well I would have bought two of this range by now if he was open about the valves used. Despite what he told me about being 'special' headphone valves both the pro and the ordinary model use bog standard commonly available valves. More fool him, I would have probably also bought replacements from him as well, to try! His loss not mine.

The Hifi World valve headphone amp (£395 assembled but also available as a kit) is a good one for 600s when connected with 300 ohm taps as well. It uses ECL83, which are a triode / pentode valve. This means you gets LOTS of class A power and Mullard ECL83s are GREAT quality and cheap.