B1K is a fascinating preamplifier.
What about parallel red MKP's with 10uF Elna SilmicII or Bipolar Nichicon Muse for more total capacity?
Work in reverse order as well
After my experiments this "energize to full body" the kick drum and bass guitar.
Yes triode curves and electrons speed flow in the vacuum , they are directly heated and Papa wise buffered them with jfet's
B1K is a fascinating preamplifier.
What about parallel red MKP's with 10uF Elna SilmicII or Bipolar Nichicon Muse for more total capacity?
Work in reverse order as well
After my experiments this "energize to full body" the kick drum and bass guitar.
Yes triode curves and electrons speed flow in the vacuum , they are directly heated and Papa wise buffered them with jfet's
I tried 100uf silmic paralleled with 6.2uf mks2. Sound was duller and less lively and bass seemed no deeper than just wima mks2 bypassed with .1uf polypropylene cap.
I do want to try polypropylene caps only but this pcb has space limitations. But it can be done. Probably my next step.
Originally Posted by Hikari1 View Post
I would love to have the soundstage and ambience of the korg with the dynamics and crisp
snare cracks on drums of my solid state preamps. Please tell me if this exists...
Try replacing the internal wiring with better quality. I've got plenty of kick with solid core gold plated internal.
NB Power supply is external so no EFI worries.
I would love to have the soundstage and ambience of the korg with the dynamics and crisp
snare cracks on drums of my solid state preamps. Please tell me if this exists...
Try replacing the internal wiring with better quality. I've got plenty of kick with solid core gold plated internal.
NB Power supply is external so no EFI worries.
100 uF is a lots..
Mine is 10 uF of Bipolar Muse UES1V100MEM1TD Nichicon | Mouser
+ 1uF MKT small size cap's mixture.
1000uF filament filter cap is bypassed with 8 uF MKP because one was found in the drawer.
Psu power resistors 10R and 270R are wire wound,. not everybody's cup of tea.
Oh yes me too I want try 10uF MKP
Mine is 10 uF of Bipolar Muse UES1V100MEM1TD Nichicon | Mouser
+ 1uF MKT small size cap's mixture.
1000uF filament filter cap is bypassed with 8 uF MKP because one was found in the drawer.
Psu power resistors 10R and 270R are wire wound,. not everybody's cup of tea.
Oh yes me too I want try 10uF MKP
Hi Hikari,
Not sure you aren't listening to LM317 (and its different synergies) than anything else in your experiments, rather than comparing 'OEM' SMPS your with linear PS.
Sad you couldn't compare your extensive PS with what Papa's recommended first hand, as only that would IMHO permit to decide if really further improvements on the original PSU design are required or not, and if Papa's design was really limited in that aera. As said, Papa vs linear didn't work in my case, but then my starting point was Papa, not 2 different options of my own. And to be completely honest as you I thought it could be easily bettered when I looked at its simplicity and the use of SMPS, but at the end following (exactly) his receipe and also what he stated as possible upgrade recommandations was the winner for me.
Good luck with your experiments and keep us posed, Jung chokes etc. are again a different fish but then these could also bring a completely different sound. Really sad you can't compare them to the original design
Claude
Not sure you aren't listening to LM317 (and its different synergies) than anything else in your experiments, rather than comparing 'OEM' SMPS your with linear PS.
Sad you couldn't compare your extensive PS with what Papa's recommended first hand, as only that would IMHO permit to decide if really further improvements on the original PSU design are required or not, and if Papa's design was really limited in that aera. As said, Papa vs linear didn't work in my case, but then my starting point was Papa, not 2 different options of my own. And to be completely honest as you I thought it could be easily bettered when I looked at its simplicity and the use of SMPS, but at the end following (exactly) his receipe and also what he stated as possible upgrade recommandations was the winner for me.
Good luck with your experiments and keep us posed, Jung chokes etc. are again a different fish but then these could also bring a completely different sound. Really sad you can't compare them to the original design
Claude
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I think something has gone wrong with my B1 Korg. I switched on my system to listen to some music and there was what sounded like RFI on the left channel. I was able to play music through the B1 Korg, but the noise kept coming through left channel. It sounds like the same noise I hear in tube amps when a tube is going bad and needs replacement.
We’ve had thunderstorms recently and I know that the power went out one night—possibly from lightning. I wonder if something might have damaged the NuTube as I left it powered on. I will make some measurements, but other than the noise in the left channel, the music sounds balanced from channel to channel.
We’ve had thunderstorms recently and I know that the power went out one night—possibly from lightning. I wonder if something might have damaged the NuTube as I left it powered on. I will make some measurements, but other than the noise in the left channel, the music sounds balanced from channel to channel.
One thing to remember is that the Plate of the tube is at a very high
impedance - the load resistor there to V+ is 330 Kohm, and it is very
susceptible to all sorts of noise pickup. Shielding and grounding
around this is important.
Korg Nutube left channel no volume
The problem was a bad solder joint on the R1 resistor. Volume fine on both channels now. I also had a noise issue which for the most part was resolved by running the GND wire for the power supply for the power amp directly between the two. I still have a soft hiss at the speakers. I have tried changing the input signal wiring to shielded wire all the way from the input RCA jacks right to the input to the power amp module. No joy. I tried allowing the 24VDC for the Korg preamp to float by not grounding the minus, No change. Next I'm going to try putting the Korg PCB into a small enclosure to see if the noise goes away.
The problem was a bad solder joint on the R1 resistor. Volume fine on both channels now. I also had a noise issue which for the most part was resolved by running the GND wire for the power supply for the power amp directly between the two. I still have a soft hiss at the speakers. I have tried changing the input signal wiring to shielded wire all the way from the input RCA jacks right to the input to the power amp module. No joy. I tried allowing the 24VDC for the Korg preamp to float by not grounding the minus, No change. Next I'm going to try putting the Korg PCB into a small enclosure to see if the noise goes away.
Congratulation RegaPedro
B1K is sound the best if closed in enclosure box.Maybe hum noise is about SMPS quality ? Greetings
I am a beginner, so sorry if this is a silly question.
I have an AS power amp with 33db gain, so I don't need the B1K gain.
Would it be possible to use the B1K as a DAC output stage, using a chip like the AD1865, adjusting the I/V resistance so that the B1K output was 1-2 volts max?
Clearly the pot (or TVC) would have to be somewhere else.
Or should I look elsewhere for a triode output stage?
Thanks.
I have an AS power amp with 33db gain, so I don't need the B1K gain.
Would it be possible to use the B1K as a DAC output stage, using a chip like the AD1865, adjusting the I/V resistance so that the B1K output was 1-2 volts max?
Clearly the pot (or TVC) would have to be somewhere else.
Or should I look elsewhere for a triode output stage?
Thanks.
You can attenuate both the input and output with pots.
You can also alter the load value of the Plate resistor. lowering it for
less gain.
All these will alter the harmonic content, so you might find yourself
readjusting the bias for the desired curve.
Thank you very much. That was the answer I was searching for.
As far as I know it's possible to reduce the Pearl gain to 40dB. This may help out.
Wish everyone a nice day.
Everything to build my preamp arrived in the mail except the Flux. So I went out to my shop and grabbed a tub of flux I use for copper pipe soldering and practiced for a while. The flux from Ebay was ordered December 9th. Its in San Diego as of yesterday. I'm not waiting, so I found some electronic flux at Ace hardware. So, I'm ready to solder. I stuffed the PCB,but I'm too chicken to start soldering. Would someone one please help me cross the street? I'm new to this hobby and would appreciate any
advice I can get. Please look at the picture of my board and see if I got it right.
advice I can get. Please look at the picture of my board and see if I got it right.
Looks pretty good to me, ideally, when you solder from the back side, the front side (like your picture), should have small mounds of solder also like the back side. This will come with practice as you cannot watch the front side to see if you get right while working the back side.
When I'm not sure the front side is "right", I solder from the from front to fill in.
The real test will be the nutube, be careful with the pins, they are very delicate.
Do you have a clip to heatsink the parts, like transistors? If not, find one, allow is best, alligator clips second best, use them on each solder joint by clipping the part close to the part so when you solder the heat from the solder dissipates.
This is a great preamp, your halfway there from your picture!
When I'm not sure the front side is "right", I solder from the from front to fill in.
The real test will be the nutube, be careful with the pins, they are very delicate.
Do you have a clip to heatsink the parts, like transistors? If not, find one, allow is best, alligator clips second best, use them on each solder joint by clipping the part close to the part so when you solder the heat from the solder dissipates.
This is a great preamp, your halfway there from your picture!