I did not take the risk of running with any other amplifier. Looks like the old test speakers voice coils are damaged testing this preamp with the loud sounds coming in, and I do not have any powered speakers. Will give another shot by removing from this enclosure and putting it outside as my other Korg which is my main preamp works perfectly fine with a LDR source/volume control. This is for a friend that I have built in a case similar sized as in the store.
Thanks
Two things seating on my bench korg b1 and your 6v6. Really excited to compare kinda tubes to tubes 🙂
The preamp I made for my son has come back to have a Trigger input connected which was always part of the plan but didn’t get done at the time.
My son was also hoping I could reduce the overall noise floor. When nothing is playing there are a variety of noises that the preamp emits from, a hiss, a steady tone, high pitched ringing etc! The noises stay the same even when there is no source connected. The noise variety changes depending where the volume is set, with the lowest volume setting having the loudest noise. The stepped attenuator I have cobbled together used good quality resistors.
If anyone has any thoughts on how I might go about reducing the noise floor I would be very glad to hear about it.
My son was also hoping I could reduce the overall noise floor. When nothing is playing there are a variety of noises that the preamp emits from, a hiss, a steady tone, high pitched ringing etc! The noises stay the same even when there is no source connected. The noise variety changes depending where the volume is set, with the lowest volume setting having the loudest noise. The stepped attenuator I have cobbled together used good quality resistors.
If anyone has any thoughts on how I might go about reducing the noise floor I would be very glad to hear about it.
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try localizing all ground connections on one point - say GND supply pad on pcb
for example - rout input RCA's ground wire to that point only..... now you have 2 feeds to it
long wires to Nutube are not helping, too
for example - rout input RCA's ground wire to that point only..... now you have 2 feeds to it
long wires to Nutube are not helping, too
Thanks, I will have a play with the grounding as you suggest.
The long wires were a design comprise to get the tube visible from the front, it would be very interesting to see how much difference that made. Maybe I can make anotherone to see.
Or I could buy another Korg, mount it on the PCB and just have the front one for show 🙂 So wasteful!
The long wires were a design comprise to get the tube visible from the front, it would be very interesting to see how much difference that made. Maybe I can make anotherone to see.
Or I could buy another Korg, mount it on the PCB and just have the front one for show 🙂 So wasteful!
find old calculator with similar display, butcher it and put display on front for show 🙂
you can even make it alive , to show volume and input
you can even make it alive , to show volume and input
I see GND OUT L R are empty..the best quick way to correct all wiring check great Korg NuTube B1 guide
with lots of photos and construction details .Thanks to 6L6 🙂 Have a nice day
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After close look at your pcb photos IN GND L R need to be connected as well with potentiometer 
Best regards
Best regards
@ DQ828
Could be an interesting upgrade at small cost change 10 uF caps for Elna Silmic II, Nichicon " Fine Gold " or a mixture of both.
Congratulations your chassis DIY work is beautiful, I like it this wood with cooper style very much
Edit: Nichikon KZ Muse are hi quality audio grade
Could be an interesting upgrade at small cost change 10 uF caps for Elna Silmic II, Nichicon " Fine Gold " or a mixture of both.
Congratulations your chassis DIY work is beautiful, I like it this wood with cooper style very much
Edit: Nichikon KZ Muse are hi quality audio grade
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The high pitched ringing is probably the resonant frequency of the nutube filament. You need to suppress the microphonics.
+ 1 🙂
Close all chassis ventilation holes do calm microphonic ringing.
B1 Korg is very, very little hot inside.
Close all chassis ventilation holes do calm microphonic ringing.
B1 Korg is very, very little hot inside.
@ DQ828
Could be an interesting upgrade at small cost change 10 uF caps for Elna Silmic II, Nichicon " Fine Gold " or a mixture of both.
Congratulations your chassis DIY work is beautiful, I like it this wood with cooper style very much
Edit: Nichikon KZ Muse are hi quality audio grade
Yes, I too was confused about this for a while. I think the MUSE are the highest quality they make.
Mark Johnson was the first person I had seen post this in the forum, so credit to him.
NICHICON CORPORATION | Product & Technology
NICHICON CORPORATION | Product & Technology
Great 🙂 Thanks
All Nichicon capacitors data sheets are available on this page :
NICHICON CORPORATION | Product & Technology with picture search
All Nichicon capacitors data sheets are available on this page :
NICHICON CORPORATION | Product & Technology with picture search
Attachments
This is a store in the UK:
HiFi Collective: Capacitor Info
But they have excellent info on caps and other components.
HiFi Collective: Capacitor Info
But they have excellent info on caps and other components.