Hello Drew,
Are you selling? I bought a pair of 26 NOS/NIB from a fella in Auckland just recently. Unfortunately, one from the pair is a dud. I am glad that the seller will replaced it with another once I sent him the proof that the tube in question was very weak.
Please PM me if you are selling. Maybe I can afford the tubes you are thinking of getting rid off.
Abe
Some of the tube prices now days are getting crazy, but it makes sense.
Even though 300Bs are being made today, teh original NOS are going at a big preamium.
Most of these tubes are not in production today and unless someone starts making them the supply will eventually go away.
It's too bad the chinese manufacturers don't seem to be able to compete with 1930 technology at a reasonable price.
Maybe when 26s get expensive enough they will step in.
Until then, expect prices to keep going up.
The big isue I see is the low availabiltiy tubes like 01A, 31, 41, 42, etc that are fun to play with but will probably never have the popularity of the 26, 45, 300B etc, that promotes new production.
Even though 300Bs are being made today, teh original NOS are going at a big preamium.
Most of these tubes are not in production today and unless someone starts making them the supply will eventually go away.
It's too bad the chinese manufacturers don't seem to be able to compete with 1930 technology at a reasonable price.
Maybe when 26s get expensive enough they will step in.
Until then, expect prices to keep going up.
The big isue I see is the low availabiltiy tubes like 01A, 31, 41, 42, etc that are fun to play with but will probably never have the popularity of the 26, 45, 300B etc, that promotes new production.
The prices are rising if people get stupid and making big big reserves
at home...The 26 will last at least 2-3 years a pair and there is no need
for you to buy a lot of them!!! I know that they will produce new 26 tubes,
emission labs will do so...So no rush....please people!!!!!!!!!
at home...The 26 will last at least 2-3 years a pair and there is no need
for you to buy a lot of them!!! I know that they will produce new 26 tubes,
emission labs will do so...So no rush....please people!!!!!!!!!
Hello,
today I first powerd my 26 pre amp and it sounds ok,
but there is a slight hum when in front of the speakers (95dB),
I am using Rods filament supply and CLCLC 50H filtering,
is this normal for 26 or shuld I put a CCS in front for the B+?
today I first powerd my 26 pre amp and it sounds ok,
but there is a slight hum when in front of the speakers (95dB),
I am using Rods filament supply and CLCLC 50H filtering,
is this normal for 26 or shuld I put a CCS in front for the B+?
Ok. I will need to draw it...
But 1meter away I can hear nothing...
I will need to looks for magnetic coupling from other devices,
I have all my components open and testing, so It can be only that...
Will keep you posted...
On sound the 26 is really something special, so sweeet...
But 1meter away I can hear nothing...
I will need to looks for magnetic coupling from other devices,
I have all my components open and testing, so It can be only that...
Will keep you posted...
On sound the 26 is really something special, so sweeet...
This is my #26 pre wiring scheme.
Two box layout (1m distance). The PSU box contains 250V (CLCLC) raw supply, the two SSHV2 (220V), and two 15V DC heater raw supply.
Two box layout (1m distance). The PSU box contains 250V (CLCLC) raw supply, the two SSHV2 (220V), and two 15V DC heater raw supply.
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I decresed the hum...changed the tube and put an volume cotrol in front,
now the hum is almost not present, only if I turn the volume pot to max...
So I guess its normal in this levels to have a little hum.
now the hum is almost not present, only if I turn the volume pot to max...
So I guess its normal in this levels to have a little hum.
Some thougths on the use of cathode bias..
Intro:
I just (re)built a '26 preamplifier. It is choke-loaded and C-out. PSU is simple but elegant: RGN1064 (X2, used a half wave), 4.7uF, 10He, 60uF, 560R, 120uF and then per channel apart stabilized using a VR-tube.
Cathodes of both '26 share the same filament psu, in series, so one on +1.5Volt and the other on -1.5Volt, centered at ground. The '26's are battery biased on the grid.
My thoughts:
When using cathode bias, imho the use of ONE filament supply would be no problem (not puristic, I know). since the '26 is biased using the voltage drop on a resistor at 1 amp, this nearly is identically to a battery bias since operating the tube at several mA will not affect the cathode bias..
Ergo, using one filament supply for filaments in parallel increases amperage thus allows for lower filament voltage..
Anybody?
Reason for asking is > just curious < ;-)
..Oh, and a picture of the pre..
Intro:
I just (re)built a '26 preamplifier. It is choke-loaded and C-out. PSU is simple but elegant: RGN1064 (X2, used a half wave), 4.7uF, 10He, 60uF, 560R, 120uF and then per channel apart stabilized using a VR-tube.
Cathodes of both '26 share the same filament psu, in series, so one on +1.5Volt and the other on -1.5Volt, centered at ground. The '26's are battery biased on the grid.
My thoughts:
When using cathode bias, imho the use of ONE filament supply would be no problem (not puristic, I know). since the '26 is biased using the voltage drop on a resistor at 1 amp, this nearly is identically to a battery bias since operating the tube at several mA will not affect the cathode bias..
Ergo, using one filament supply for filaments in parallel increases amperage thus allows for lower filament voltage..
Anybody?
Reason for asking is > just curious < ;-)
..Oh, and a picture of the pre..
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I will...Now I am just testing,
so it can take some time before putting into some nice case.)
so it can take some time before putting into some nice case.)
The power supplies with 120uF and 220uF final caps - are these electrolytics? I had better results with all polypropylene caps, especially the final cap.
Errh, yes.. My attempt to share diy-audio experiments and experiences ..
Hi Andy,
Yes, all nasty electrolytics, for starters that is.. First cap however is a Dubilier PIO.. I do not have that much free space in the cabinet to be able to fully MKP the preamp at the same uF..
In some cases it is worthwhile trying to "shield" the '26's. A simple aluminum cage behind and over the '26 will take care of any residual hum caused by stray-fields.. See picture.. Cage must be connected to ground, but will have effect without.
Sometimes it helps as well to cut a piece out of a tin can and wrap it around the valve-base only..
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What I meant is filament bias, not cathode bias.. sorry..
Some more diy-'26-pron in picture: Mercury HG3 by Electromekano.
