• 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.

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I have run about 4 records through it so far and it sounds good. I'ts very neutral. The convenience of having the built in linestage preamp makes it highly versatile. The pictures don't show it, but I have since wired in another Aux input for a DAC.

I love this chassis. I have used the version without the knobs on another phono preamp. This one worked perfectly for this build.
 
Is it an MM or MC stage, or switchable? I like the placement of the rotary switch and pot; I should have done that with mine to reduce wire length, but I used shielded cable and have had no issues with noise/hum.
Yes, very nice chassis, but I wish the shipping wasn't so expensive. Still, mine arrived very quickly and in good shape.
I'm taking mine to BAF this weekend.
 
Is it an MM or MC stage, or switchable? I like the placement of the rotary switch and pot; I should have done that with mine to reduce wire length, but I used shielded cable and have had no issues with noise/hum.
Yes, very nice chassis, but I wish the shipping wasn't so expensive. Still, mine arrived very quickly and in good shape.
I'm taking mine to BAF this weekend.

MM stage. Thanks! It was my first time using extension rods. My only issue is that when the turntable is still connected and playing music, the stray capacitance around the switch leaks when its switched to another input and sound comes through. I just have to make sure the turntable is off when using the other inputs.
 
Posting to brag, of course, but also to motivate me to finish sooner. Critique and suggestions welcome

P-P KT88 amp with 4P1L drivers and Lundahl IT configured to SE-to-PP
4P1L's biased by LED bars, running at 25mA, 210V on plates

KT88's on fixed bias via Pete Millet's regs, -36V or so, 350V on plates, 90mA idle current
DC on filaments, Rod Coleman's regs for 4P1L, MIC29502 based regs for KT88's
 

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P-P KT88 amp with 4P1L drivers and Lundahl IT configured to SE-to-PP
4P1L's biased by LED bars, running at 25mA, 210V on plates

KT88's on fixed bias via Pete Millet's regs, -36V or so, 350V on plates, 90mA idle current
DC on filaments, Rod Coleman's regs for 4P1L, MIC29502 based regs for KT88's

cool stuff albeit quite busy down there :)
any URL reference for the LED bar circuits ? Holding the 25 mA ???
 
I've seen busier :)
This is the LED bar I used: SSA-LXB10IW-GF/LP Lumex | Mouser 香港
They have some for 30mA if I remember or maybe even more
thanks for the reference. So you even made some little PCBs to hold them with voltage-marked pins ! The attention to the details is great ;)
BTW I like the idea of building the amp on such a metal plate instead of under a top-plate. Allows for less apparent screws. I look forward to see the finished casing.
 
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During my last build (SE 300B) I made a promise to myself I am not flipping an amp over and over anymore
Not to want to pollute the thread but when taking the pic you had a grey t-shirt and the weather was mostly good with a few clouds. No I'm not the NSA, but the top of your KT88 are decent mirrors :) Other thing I noticed, a bolt is missing in the middle of your left rectifier bridge.