tube suggestions

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22tape
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tube suggestions

Post by 22tape » Thu Aug 14, 2008 12:52 am

hey guys. i just bought an Korg ESX-1 Sampler. i want to replace the existing tubes with meaner ones. problem is, i know shit about tubes. i'm looking for something that will dirty things up nicely....the meaner the better, actually.

any suggestions as to what kind of tubes? where to buy?

thanks!

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wetterberg
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Post by wetterberg » Thu Aug 14, 2008 12:57 am

I think you'll be in a mess of trouble trying to replace it :-?

I'd get a tube preamp instead?

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Luka
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Post by Luka » Thu Aug 14, 2008 1:51 am

perhaps email ken stone and ask him

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futuresoundsystems
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Post by futuresoundsystems » Thu Aug 14, 2008 4:28 am

Personally I really wouldn't start doing that. AFAIK (I'm not a big fan of tubes so don't take my word for it) with the different ratings of tubes and voltage supplies, you'll just get yourself into a mess in the end. Either you're going to have to add extra circuitry (I doubt there's much if any room for that in the ESX) or you're going to blow something. I'd stay away from it.
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Chrome Dinette
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Post by Chrome Dinette » Thu Aug 14, 2008 4:52 am

I suspect the tubes in that device are little more than decoration. At any rate they are 12ax7's and are running on very low plate voltage, making them not very useful. Any of the same family of twin triode tubes could probably be put in there(12au7, 12at7, 12ay7) but you probably wouldn't notice a difference.

To make things meaner, just run that device into something else that does what you want.

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Kent
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Post by Kent » Thu Aug 14, 2008 10:54 am

If the 12AX7 tubes are running at 'starved' plate voltages, then they are just being used as distortion devices. You might get slightly less gain by swapping them out for 12AU7, 12AT7, etc., but there won't be much of a difference. I'd just leave them 'as is' & follow Chrome Dinette's advice of cascading the entire unit into another distortion device.
Last edited by Kent on Thu Aug 14, 2008 2:06 pm, edited 1 time in total.

22tape
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Post by 22tape » Thu Aug 14, 2008 1:49 pm

great, thanks guys. guess i'll have to wait for metasonix modules then!

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parasitk
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Post by parasitk » Thu Aug 14, 2008 4:50 pm

22tape wrote:great, thanks guys. guess i'll have to wait for metasonix modules then!
that's the spirit!

22tape
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Post by 22tape » Mon Aug 18, 2008 6:00 pm

wetterberg wrote:I think you'll be in a mess of trouble trying to replace it :-?

I'd get a tube preamp instead?
i know the zvex nano amp....what other tube preamps would you guys recommend i check out?

thanks!

zerosum
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Post by zerosum » Mon Aug 18, 2008 10:55 pm

Metasonix TM-7
You can also use it as an oscillator in addition to it being a fun pre amp.

[GVideo]http://video.google.com/videoplay?docid ... 0934&hl=en[/GVideo]

The TM-1 is fun with the TM-7 too.

Pretty much plugging any drumbox into any preamp cranked to the max will bring about overly distorted fart noises trashing the signal into fuzz,
get a cheap preamp and and mess around, or get a TM-7 and a cheapass pre and run them together. Just remember to have fun :hihi:

There are quite a few DIY schems out there as well for some hellish tube boxes/horrible inventions we love to exploit :sb:

chrome dinette and not breathing have frankensteined some nice gadgets.

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ehdyn
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Re: tube suggestions

Post by ehdyn » Wed Aug 27, 2008 12:17 am

22tape wrote:hey guys. i just bought an Korg ESX-1 Sampler. i want to replace the existing tubes with meaner ones. problem is, i know shit about tubes. i'm looking for something that will dirty things up nicely....the meaner the better, actually.

any suggestions as to what kind of tubes? where to buy?

thanks!
Not to be contrary, but you do want to replace the tubes. Korg is putting GT's in when returned from repair in the U.K.

Here's a thread on the subject
http://www.korgforums.com/forum/phpBB2/ ... hp?t=35175

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metasonix
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Post by metasonix » Wed Aug 27, 2008 2:22 am

My opinion:

I seriously doubt the tubes in those Korg things are even in the circuit. It's commonplace in today's gear to install a tube under a plastic window--but not operating.

If it DOES actually process the signal, you could try a 12AV7 or 5965 instead. They are old computer tubes, and have awful distortion and cutoff nonlinearities.

Hope the tube isn't soldered into its PC board. Good luck!

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Kent
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Post by Kent » Wed Aug 27, 2008 8:13 am

I just wanted to check into all of this so I cracked open my EMX-1.

The tchooobs (tubes) are, amazingly, in rather nice ceramic sockets.

They are definitely in circuit as pulling either 12AX7 (Electro-Harmonix units in my EMX-1) will cut either the Right or Left output. The funny thing is that the left tube cuts the Right output and vice versa.

Naturally, as per the norm for all things 'pro-sumer' these days, the tubes are backlit with Yellow SMD LEDs... Rock on with your fake self... :razz:

The tubes get amazingly hot. The power supply is a 9VAC affair and is rated for 3 Amps.

The EHX tubes in mine are not microphonic in the least; which is a nice change of events for OEM tubes. I gave 'em the old "rap 'em with a Sharpie pen" test.

There are two tiny-ass trim pots in there. I'm guessing that they are used to balance the tubes in order to maintain a proper Left/Right stereo image.

The gang (knuckleheads?) on the Korg forum don't know how to go about testing things at equal levels and accounting for the variables. I'd take their comments (as of 27.08.2008) with a great deal of healthy skepticism. Or, you can do as I do lump them all in together as uneducated goat-tards.

Eric, I'm going to check out those tubes you mentioned. Could be a good deal of fun.
Last edited by Kent on Wed Aug 27, 2008 12:30 pm, edited 1 time in total.

22tape
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Post by 22tape » Wed Aug 27, 2008 11:57 am

Kent wrote: Eric, I'm going to check out those tubes you mentioned. Could be a good deal of fun.
cool, i'd be interested in the results.

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