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- Valve Types:
- Valve Names:
  - ECC83 (12AX7)
  - ECC82 (12AU7)
  - ECC81 (12AT7)
  - EL34
    The EL34 (6CA7) valve was originally introduced back in 1949 by Philips the parent company of Mullard.
    Among the first amps to use EL34 valves were the Marantz 2 (1955), Dynaco Mark II (1956), and the rare Pye Mozart, a single-ended 9-watt British unit from 1956.
    The EL34 valve’s popularity was sealed when Jim Marshall selected it for his JTM45 guitar amp in 1965. He went with it because it was cheaper and easier to get in England than the 6L6 he had used previously.
    That amp went on to become a standard for the British blues-rock sound. The EL34 tube also found its way into Hiwatt, Orange, and Laney amps, all made in Britain, as well as the popular Canadian-made Traynor brand.
    Although Philips no longer makes the EL34 tube, it is manufactured by Electro Harmonix, JJ Electronics and Sovtek which deliver top quality output tubes with stunning tone.
    Of course, many amplifier manufacturers rebrand these valves in their own name.
  - EL84
  - KT66
  - KT77
  - KT88
  - 5881
  - 6550
  - 6L6
  - 6V6
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The KT77 Valve and KT77 Tube

      EXCELLENT  
   Based on 23 reviews 
    
 
 
 
   
 
 
       Posted on Google  
   
   Stuart ukguitarampguy 
 
 
 
 Trustindex verifies that the original source of the review is Google. I'm a Berkshire based amp tech and have fitted literally hundreds of valves sold by Ampvalves. Always reliable and I get a personal servivce too if I have any queries. Very good company in my view.
  
 
      Posted on Google  
   
   Isabelle Worthington 
 
 
 
 Trustindex verifies that the original source of the review is Google. Great service , friendly and helpful very knowledgeable. Thank you so much amp now working as it should.
  
 
      Posted on Google  
   
   Anthony White 
 
 
 
 Trustindex verifies that the original source of the review is Google. Absolutely brilliant service from Ampvalves.co.uk
I will not hesitate to use this excellent company again.
Easy website to navigate, with valves arriving well packaged and on time.
Ampvalves provide a service I've not experienced for years. Try them. You wont be disappointed.
  
 
      Posted on Google  
   
   Steve 
 
 
 
 Trustindex verifies that the original source of the review is Google. New valves arrived today from Ampvalves. Awesome. I loved the sound of my Victory V40 when I bought it new - and now it's even better. Great valves and superb customer service. Highly recommended.
  
 
      Posted on Google  
   
   Alex Fischer 
 
 
 
 Trustindex verifies that the original source of the review is Google. I recently purchased a replacement tube set for my Line 6 DT25 Head amp from Ampvalves.
The website is very user-friendly and makes it easy to find the perfect tube set for your amp.

Due to an error by the parcel service, my shipment did not find its way to me. After contacting the support, I was helped immediately and competently.

The quality of service was truly exceptional and exceeded my expectations. A special thanks to Barry Tyler. Hey Barry, you did a very good job.

The tube set arrived afterwards in excellent condition, exactly as described on the website.

The quality is remarkable. It’s well worth the money for their high-quality tubes. I highly recommend the tubes from Ampvalves.
Also, my amp gives grateful feedback with a wonderful fresh sound.

Alex from Switzerland
  
 
      Posted on Google  
   
   Max Bevan 
 
 
 
 Trustindex verifies that the original source of the review is Google. Will never buy valves anywhere else. Incredibly well set up website to find the correct tubes. Very well priced and very quick delivery. Will be recommending to everyone! Thank you!
  
 
      Posted on Google  
   
   David Dawkins 
 
 
 
 Trustindex verifies that the original source of the review is Google. Amazingly helpful, truly above and beyond with their customer experience. I was pretty stuck, through my own fault, and still they went the extra mile to get me back up and running. Thank you so much.
  
 
      Posted on Google  
   
   kev herbert 
 
 
 
 Trustindex verifies that the original source of the review is Google. Cant fault them extremely helpful & prompt with delivery.
  
 
      Posted on Google  
   
   Steven Wilson 
 
 
 
 Trustindex verifies that the original source of the review is Google. Excellent place to grab your amp valves. Great choice of valves, amazing customer service and prompt responses to queries via email. I was unsure of the best valves to use for my amp and sound, they gave me great advice. When I ordered the valves I used the wrong delivery option and they even sorted that out for me. Highly recommended.
  
 
  
  
 
    Verified by Trustindex  Trustindex verified badge is the Universal Symbol of Trust. Only the greatest companies can get the verified badge who has a review score above 4.5, based on customer reviews over the past 12 months. Read more

The KT77 Valve. Buy them here and learn all about this awesome valve.

The KT77 is a power output valve used in some guitar amplifiers. Marshall have used these in several of their designs in the past.

Normally you will find the amp can use either a KT77 valve or an EL34. They are fairly interchangeably but see my comments below regarding the tone differences.

First let’s look at what the ‘KT’ stands for in the KT77 valve. Well, these valves, like many power valves are basically TRIODES. That means they have three main electrodes. The cathode, the anode (plate) and the grid. So the ‘T’ stands for ‘Triode’. The ‘K’ stands for ‘kinkless’. And no, that’s nothing to do with the sexual preferences of this valve.

Many valves exhibit a ‘kink’ in the sine wave and this manifests itself as slight distortion (“Oh no… distortion in a guitar amplifier…. Whatever will we do???”) The KT77 is designed to have no kink in the output sine way. If that’s confusing they are actually pentodes with 5 electrodes! Ah well. Too much info.

Ok, so what does that mean? All other things being equal it will give you a cleaner sound with more clean headroom. If you play any kind of distorted sound (metal etc) then you don’t need KT77’s in your amp. Use an EL34 instead. If you’re into Hi Fi or want a very clean guitar sound you should go for KT77.

GEC optimised the KT77 valve for use in audio application. So this makes KT77 the ultimate ‘EL34’ for audiophile.

Here’s what JJ say about their KT77 Valve.

“KT77 is a beam power pentode with octal base. So it can be used in most EL34 amplifiers. It has more power, fatter bass and more headroom than the EL34 and E34L while providing very detailed tones.”

Here is what one user says: “Tone-wise the KT77 is somewhere between an EL34 and a 6L6…
bigger bottom end, nice detailed highs… more headroom too.”

We always recommend JJ KT77 valves.This is because they guarantee you will get awesome tone and they don’t cost a fortune. Remember, JJ is one of only three valve manufacturers in the World.

The KT77 Valve and KT77 Tube

The KT77 Valve. Buy them here and learn all about this awesome valve.

Here’s what JJ say about their KT77 Valve.

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