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Little Dot MKIII, faulty driver tube, GE5654 alternative in the UK?

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Hi all,

I have a friend who has a Little Dot MKIII headphone amp. He complained of a developing loud hiss, only in the right channel, since about 2 weeks a go. I suggested he try swapping the tubes, left to right, right to left, to see if it was perhaps just a faulty tube.

We've come to the conclusion that it is a faulty driver tube, which is apparently a "GE5654". When this one is swapped to the other channel, the hiss follows.

I don't know anything about tubes, but he needs a replacement. I have searched and can't find much on "GE5654", let alone where to get a replacement in the UK!

Does anyone happen to know of any alternative tubes which would be a drop in replacement, which is easily obtainable in the UK? I don't really know what I am looking for to be honest!

I have come across a UK seller, www.bel-tubes.co.uk, which lists a lot of different tubes, and have found a '5654', no GE, which says to refer to "CV4010". Might this be what I am looking for?

Many thanks in advance!
 
Learn to use TDSL, when searching for substitute tubes. You'll find that CK5654, CV10442, CV4010, CV5216, CV5893, and CV8246 are suitable as 5654 replacements.

Both tubes should be replaced with pieces of the same brand out of the same production run.

GE is General Electric, one of the world's largest corporations. CK is something Raytheon put on the stuff they made.

US tubes identified by a 4 digit number are "industrial" types.
 
If he uses the jumpers that came with the amp he can also use EF91, EF92 which are available as Mullards. Also are meant to be very nice sounding.


Chelmer valves might well have them. They won't be dear (I wouldn't be paying any more than about £5 each). They are available on Us ebay for a $5.


I have one of these amps. Very nice it is too and small money. I have a firend in the US who got some mullard EF92 for me and is sending them on. He also has one of thes amps and likes it a lot too.

There are fewer choices for the power amps, 6H6 and 6H6Pi will drop right in and you can use 6H30P if you can change the cathode resistor from 68R to 120R.


Fran
 
Eli Duttman said:
Learn to use TDSL, when searching for substitute tubes. You'll find that CK5654, CV10442, CV4010, CV5216, CV5893, and CV8246 are suitable as 5654 replacements.


Thanks for that link.

Both tubes should be replaced with pieces of the same brand out of the same production run.

Yeah I figured as much :) He also figured that would be a good idea.


woodturner-fran said:
If he uses the jumpers that came with the amp he can also use EF91, EF92 which are available as Mullards. Also are meant to be very nice sounding.


Chelmer valves might well have them. They won't be dear (I wouldn't be paying any more than about £5 each). They are available on Us ebay for a $5.


I have one of these amps. Very nice it is too and small money. I have a firend in the US who got some mullard EF92 for me and is sending them on. He also has one of thes amps and likes it a lot too.

There are fewer choices for the power amps, 6H6 and 6H6Pi will drop right in and you can use 6H30P if you can change the cathode resistor from 68R to 120R.


Fran


At the moment I don't think he's interested in changing it too much or anything, he would just like it working again. I imagine he's missing the quality of sound it puts out dearly! I have linked him to this thread / forum if he decides otherwise though.

Chelmer valves looks promising. Though none of the tubes mentioned in this thread so far appear to bring results on their shop's search. On the plain website search there are results with "Add to quotation request". I'll get him to do that I think!


Thanks all!
 
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