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Nu Screamer

Started by drog_trog, January 06, 2018, 04:14:52 PM

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fair.child


mjg

I also saw this the other day - tutorial for making a PCB with the nu tubes, and they have put their gerber files up for free:  https://www.rs-online.com/designspark/design-of-a-korg-nutube-amplifier-part-4-build-and-test


Frank_NH

And now this...

http://tagboardeffects.blogspot.com/2018/01/nuverdrive.html

In the Nuverdrive circuit, an op amp gain stage drives a NuTube gain stage into distortion, which is somewhat un-screamer-like but may sound pretty good (if the demo video is any indication).   Certainly a lot of room for innovation and creativity.  Of course, at $50 for a single NuTube, one would want to do a lot of breadboarding before committing the NuTube to a build.  :P

PS:  Will Madbean be tossing his hat into the NuTube ring??  :D


Aleph Null

Quote from: Matmosphere on January 07, 2018, 05:57:05 AM
Also a little surprised that it's supposed to cost 100$ more than those Vox amps.

NuTube is a Korg product. Korg also owns Vox. I'm sure a big part of the cost for the Ibanez pedal is in licensing the technology from Korg.

gordo

Quote from: Muadzin on January 07, 2018, 04:00:04 PM
Quote from: jimilee on January 06, 2018, 06:53:45 PM
That sounds really good, that's a lot of money for a non gigging musician though.

Aren't those usually the ones who can actually afford these? As they got real paying jobs  ;)

Ouch.  Sad but true.  If I could afford then what I can build now...I'd probably still have a real job...

Sigh...
Gordy Power
How loud is too loud?  What?

bsoncini


culturejam

Quote from: bsoncini on January 09, 2018, 04:57:05 AM
http://www.diystompboxes.com/smfforum/index.php?topic=109894.0

Some good info on the nutube here

Nice. Thanks for sharing the link.

Here's a good quote from Paul Remark from that thread:

Move on. Nothing to see here. This is all VERY old-old-stuff.

It is Noritake's vacuum fluorescent display (VFD). We all know VFDs. They are/were a favorite in microwaves, VCRs, DVDs, and car-audio 1980s-2010. They were expensive but it cost very little to have special words, symbols, logos built-in. My 1994 truck heater has a VFD with little hands/feet/windshield icons. The present DVD machine here has a VFD with the counter/time and symbols for the too-many types of DVDs/CDs it can play. The X-Plod radio in the car is an eye-popper with every type of EQ (jazz/classic/rock/easy), a blazing waterfall (I guess) for volume indication, etc.

A VFD _is_ a vacuum triode, plus some glow-stuff, and recently they put dozens or hundreds of triodes in the bottle.

The main difference between an amplifying vacuum triode and a VFD (aside from the glow-stuff) is that a VFD needs very little current or gain. The geometry is optimized for low-low cost and silk-screen design, not to be an amplifier.

The original VFD is from 1959, the DM-160 from Philips. That one made you diddle the control grid directly. The up-surge of many-object VFDs in the 1980s was due to integrating a digital controller to allow a few lines to control a hundred objects (you can't diddle the grids).

You don't have to get the memos to suspect the VFD business is on a decline. New toys use LCD/Plasma displays so they can put up ANY image, not just built-in images. Cheap new toys (my 2013 microwave) fall back to digit-only green LED (to make the fancier color LCD models look better). VFD is in the crack, and the crack must be narrowing.

So some guy from Korg was crying in his beer (sake?) about the high cost and poor life of 12AX7 and similar devices. And some guy from Noritake was under the same table crying about the fade-out of VFD production and his job. Each heard the other say "vacuum", and after swapping a few curves they realized that Korg could use the mature but going-out-of-style VFD foundry to make low-performance vacuum triodes at going-out-of-business prices.

While the digital decoder would be left out, VFDs usually have a "high"(ish) voltage converter inside which avoids one issue.

It is what it is. A small to very-small vacuum triode of poor perveyance (low conductivity) but "the right curves" and proven long life (with declining brightness/current). Small bent signals should be (are) very easy. The fact that the foundry machinery now has capacity to spare is a big economic bonus.
Partner and Product Developer at Function f(x).
My Personal Site with Effects Projects

matmosphere

Okay so only 50 years newer than vaccuum tubes.  ;D

But who in there right mind still uses tubes for anything!  :o :o

I get that this is old technology and might not end up being super exciting. But as guitarist/ builders we are using this stuff in ways that are counterintuitive to engineers. It would have been crazy expensive to launch r&d on this for a small market like guitar amps, let alone pedals which didn't even exist, when it first came about. within 10-20 years everyone moved to IC's and transistors because they were reliable and cheap by then.

Perhaps it's not jus opportunistic. Maybe the  economics finally made sense to try something like this out, because they probably didn't in 1960.

Basically I'm just saying maybe we shouldn't dismiss it just yet. Maybe we should let ours ears be the judge.

Aleph Null

Quote from: Matmosphere on January 09, 2018, 10:38:49 AM
Basically I'm just saying maybe we shouldn't dismiss it just yet. Maybe we should let ours ears be the judge.

I would agree. If it sounds good, it is good. Bonus points if it's also cheap! I prefer the sound of the NuTube Screamer to the regular 808 in demos (though, I've never liked the TS sound) and I preferred the sound of the new Vox amps to an old AC10 compared head to head (pun intended). That aught to count for something.

somnif

Quote from: Aleph Null on January 09, 2018, 01:11:21 PM
Bonus points if it's also cheap!

That is the current major issue with the things. Even in bulk the cheapest I've been able to find them is 40$ a tube. Its 50+ if you just need one at a time. I'm sure companies under the Korg umbrella source them a bit cheaper, but its still several times the price of most sub-mini tubes on the market.

Aleph Null

Quote from: somnif on January 09, 2018, 01:18:06 PM
Quote from: Aleph Null on January 09, 2018, 01:11:21 PM
Bonus points if it's also cheap!

That is the current major issue with the things. Even in bulk the cheapest I've been able to find them is 40$ a tube. Its 50+ if you just need one at a time. I'm sure companies under the Korg umbrella source them a bit cheaper, but its still several times the price of most sub-mini tubes on the market.

So how many hours of operation are the sub-mini tubes rated for? I thought I saw the NuTubes rated at 300,000 hours (maybe 30,000?). Unless that's orders of magnitude more than the sub-minis, I don't see a reason to bother.

somnif

Quote from: Aleph Null on January 09, 2018, 02:27:11 PM
So how many hours of operation are the sub-mini tubes rated for? I thought I saw the NuTubes rated at 300,000 hours (maybe 30,000?). Unless that's orders of magnitude more than the sub-minis, I don't see a reason to bother.

If I remember right, most tubes are rated in the 5k-10k hours range, but given the nature of NOS stock things get weird at times. So, the nutube (30k) is 3-6 times longer, and costs 4-8x as much. I suppose it Kinda evens out, but time will tell.