Has anyone tried to power the Korg Nutube pre-amp using 18650 Li-Ion batts?
These batts can be bought at a reasonable price. A Samsung 3000mAH 18650 batt will run you $4.99 each.
Get 7 of them, you get 3.7v x 7 = 25.9v. Get a simple linear regulator to get 24v from the batt pack.
With 3000mAH, one should be able to power the pre-amp for 50 hrs or so.
Has anyone tried it?
These batts can be bought at a reasonable price. A Samsung 3000mAH 18650 batt will run you $4.99 each.
Get 7 of them, you get 3.7v x 7 = 25.9v. Get a simple linear regulator to get 24v from the batt pack.
With 3000mAH, one should be able to power the pre-amp for 50 hrs or so.
Has anyone tried it?
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Hi Kuro, not done what you mentioned but I have run my B1K from my bike battery(54~48v), I had a buck converter to lower the voltage so I didn't get any more purity I don't think but I do get a cycle into my battery in the offseason. I should look into a regulator circuit. if you have one send me a photo. Thanks
If you use a regulator after the battery, which you will want to, the gains of pure dc might be lost. Not to mention there is so much CRC filtering on the board and a zener for the heaters...
But try it. Give us a report. Personally, I like a linear supply (lm317) better than smps and I can hear the difference. So, give it a shot.
But try it. Give us a report. Personally, I like a linear supply (lm317) better than smps and I can hear the difference. So, give it a shot.
I'll probably use a LT1085 and adjust the output voltage to 24v.
I've 4 Samsung 16850 batts coming, but they're for testing the USB Regen. I want to see if USB Regen will benefit from the 16850 batts first.
My experience with batteries is limited, I have used them in phono stages before but people say lithium ion and nicads don’t sound good. Alkaline and lead acid are better.
I found that to be true when comparing nicads vs alkaline. But the voltages are slightly different as well.
I still use a battery powered MC step up, I found it to be better than lm317. For the mm section I found a shunt regulated linear supply to be better than batteries.
But it’s fun stuff to try out. On the korg B1 it would be worthwhile to try bypassing the CRC filtering or a separate supply or separate regulator for the heaters. But this is obviously a high distortion design so really you are tuning subjectively instead of objectively.
I found that to be true when comparing nicads vs alkaline. But the voltages are slightly different as well.
I still use a battery powered MC step up, I found it to be better than lm317. For the mm section I found a shunt regulated linear supply to be better than batteries.
But it’s fun stuff to try out. On the korg B1 it would be worthwhile to try bypassing the CRC filtering or a separate supply or separate regulator for the heaters. But this is obviously a high distortion design so really you are tuning subjectively instead of objectively.
Can folks that are interested in a board run hit me with a direct message please? Its easier to collect the responses together that way rather than fishing through the thread.
Thanks!
--Tom
I know different batts sound differently. I was playing with lead acid, those gel type, and different brands sounded differently.
So it is entire conceivable that I can get a different sound with Li-ion vs alkaline. But it is worth a try.
I intend to keep the CRC circuit in there, this should lower any battery chemistry noise further, and I don't want to use a super regulator after the batt pack if I skip the CRC circuit.
I ended up just buying a new Nutube for my pre amp as the previous one was very microphonic. I also bought some rubber mounts for the board that someone suggested. Now it's very silent, and I get absolutely no ringing noise from switching inputs or tapping the case pretty hard. I don't even have to do any mods or tricks to the tube, this one is much better.
I bought the B1 Korg PCB and nutube a little while back not wanting to miss out on this little gem. When the Completer kit and chassis became available in the store again I said, "Why not? It'll be my birthday soon."
It was an absolute joy to build this kit. Thanks for the build guide 6L6!
So easy compared to all the design-the-case-from-scratch stuff I've done before this. Didn't even have to trouble-shoot, just checked voltages and was up and running. Got lucky and gain matches pretty well between channels. Tube is only slightly micro-phonic, mine only rings if chassis is bumped and damps out within a few seconds.
The only modifications I made to the kit where:
* Used terminal blocks to ease future mods.
* Used different 1000uF caps I had on hand.
* Deviated from the wiring diagram with twisted ground on each signal and starring the grounds at the board using my own teflon insulated cat5 and used larger gauge power wiring.
(I'm working on a wiring diagram of what I did if anyone is interested. Way easier to hook up than to to draw though.
)
* And of coarse a blue LED with 2.2Mohm limiting resistor.
This amp is just what the M2 needed to attain a more balance tone.
I always loved the mids of the M2 but the B1K beefed up the low end and sweetened the sound.
I don't say where's the bass anymore.
Finding I prefer the negative phase H2. Still playing with how much H2, now at 1%.
This little amp is so cool. Thanks Pa and everyone at diyA that helped make this kit happen. I'm really happy with the results and enjoying the music it makes.
Cinco
It was an absolute joy to build this kit. Thanks for the build guide 6L6!
So easy compared to all the design-the-case-from-scratch stuff I've done before this. Didn't even have to trouble-shoot, just checked voltages and was up and running. Got lucky and gain matches pretty well between channels. Tube is only slightly micro-phonic, mine only rings if chassis is bumped and damps out within a few seconds.
The only modifications I made to the kit where:
* Used terminal blocks to ease future mods.
* Used different 1000uF caps I had on hand.
* Deviated from the wiring diagram with twisted ground on each signal and starring the grounds at the board using my own teflon insulated cat5 and used larger gauge power wiring.
(I'm working on a wiring diagram of what I did if anyone is interested. Way easier to hook up than to to draw though.
)* And of coarse a blue LED with 2.2Mohm limiting resistor.
This amp is just what the M2 needed to attain a more balance tone.
I always loved the mids of the M2 but the B1K beefed up the low end and sweetened the sound.
I don't say where's the bass anymore.
Finding I prefer the negative phase H2. Still playing with how much H2, now at 1%.
This little amp is so cool. Thanks Pa and everyone at diyA that helped make this kit happen. I'm really happy with the results and enjoying the music it makes.
Cinco
