• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

6V6 line preamp

Those tubes look kinds smoky:D Did you compare to modern version yet?

Nice job, BTW.

I got these for my rebuild. Thinking about getting BudP to wind me some for the load

heh. Smoky:) Its RCA Black anode matched. well I think I have some 2-3 hundrish 6V6es laying around. What do you suggest?

I think Im gonna work me down on the current scale and skip the opt cap for a tranny instead. Theres some nicer tubes growing in 1000th around. I'll throw it to you if you catch;)

/S
 
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Mmm. Rail ripple is there. But also grounding and microphonics actually. I tried a double inversed 2007 to ground but it didnt match with my other equipment. This is a start for the feeling of sound. Impedance is the cruical thing for sounds in in pre's. I also do AC heating now. I will work it thru.
 
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Mmm. Rail ripple is there. But also grounding and microphonics actually. I tried a double inversed 2007 to ground but it didnt match with my other equipment. This is a start for the feeling of sound. Impedance is the cruical thing for sounds in in pre's. I also do AC heating now. I will work it thru.

Microphonics are minimal on mine in CF mode with the new Tungsol. Try some elastic rings between bases and chassis. Some NOS are looser than others so swap some to see which one is quieter. Can it be the chokes pick some 50Hz field also? Maybe from the AC heater cable runs.
 
Its all very rough now, but as I like the sounds I will go down on it. OPT signal has long antenna wires. As usual I started with lowish C in the filters, usually it needs to be worked up in SE.

I will start measure the rail ripple tomorrow. But, as I said, in anode followers we usually try to filter the upper rail. But think about it, we have actually 2 rails, plus and gnd. And here we're taking signal from just above gnd rail.
 
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Its all very rough now, but as I like the sounds I will go down on it. OPT signal has long antenna wires. As usual I started with lowish C in the filters, usually it needs to be worked up in SE.

I will start measure the rail ripple tomorrow. But, as I said, in anode followers we usually try to filter the upper rail. But think about it, we have actually 2 rails, plus and gnd. And here we're taking signal from just above gnd rail.

When you will sort out the build its very clean smooth and rhythmic. My bro run some ''new disco'' style mixes on digital recording he did off his mixer at work today and it pumped.
 
Mine was very quiet first go round. Not until i tried tube rectifier did i have trouble, but i am a greenhorn. I had to wipe off my tablet screen when i saw that tube collection. Mine are nos rca. Tungsol sounded good enough for me to warrant the cost. If Salas' RIAA imoresses like this pre, he will fill my entire chain, with the exception of the main amp.
 
and it pumped.

I dont know about your experience, and even less about your febless but just that is to my experience the hardest to accomodate with the other sound we all like. If you dont have the punch, when the stick hits the bass drumskin and when the guitarrist bends the strings... where are you in softish voices anyway.

CFs usualy didnt get me anyway b3, I'm to unexperienced, but I really think stong tamed CFs is the ****. I have listened to so many preamps to so many poweramps and all I can say is. get a decent preamp b4 you put the money elsewhere. Imp is the ****.

/S
 
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Gonna connect it up to some old MOSFET monoblocks tomorrow. I nailed late in night the bastard failure. Lets check how they will sing together. They got 30dB gain that I measured. I.e. plenty for CF as driver.
 

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Buzz

then you'll ask for Ultrasymmetry toob stage

and then we'll make Mini XS amps

:rofl:

I am trying to stay away from these damn glow plugs, but an LED just doesnt have the same allure. I have made the commitment that a tube power amp has to be the last thing, cause I want to do it right, which probably means dropping big coin. Tube Xs, shouldn't we call it Xs' daddy:D

Pleas understand Stajo and ZM, that I am official US part disposal facility, in case you had any "outdated" parts. Hell, I'll even take new parts....;)
 
Well Buzz, if things were sorted out by the chisel, why dont go back? Changing your setup to "better" parts can get you all sorts of problems. Oscillation is one of a biatch. She can show up anywhere you least expect.

As for the goodies, well they are here in sweden, mostly on a boat actually. But its diy friendly prices if you miss anything.

/S
 
Uff. Its not an easy task to get 6,3 ripplefree vdc from 6 vac. But it can be done :zombie:

Low drop shottkys and a C-L-C-R-C-R-C:eek:

It was for testing if ac on filaments was the bad guy. Seems like it wasnt:mad:

Well, I'll ad some more capacistance to the railfilter, cause I dont think I will get voltage enough from this lil tranny with an SSHV. But first I will enjoy Marleys Legend. Ripple is inaudiable in the sofa, its just with the ear in the cone.
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Have a good weekend.
Staffan