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Tube sound without the tube! (almost)

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#21
Soonerorlater said:
Thats clever, clearly you have borrowed that idea from optical 3D theory only in this audio application your exploiting the least known fact that one ear ( I can never remember which ) hears higher frequency sounds a fraction of a second later than the other thus this effect can be exploited by heater polarity to produce pseudo stereo signals that can be decoded by the switched on brain.

I am in awe😛
Click to expand...

You are almost correct: flipping polarity of heater causes vertical deflection change of the soundstage.
 
#26
panomaniac said:
Now here is a very nifty circuit that I came up with by accident, just trying things out. It gives any signal that great "tube sound" super easy. OK, you do have to use a tube, but no power supply! It's passive line level.

Just about any tube will do, triode, pentode, tetrode. I've used this with various tubes including the 12AX7, EL34, 6SN7 and some Russian EL84 types. They all work and give the signal that rich harmonic warmth of tube sound, but without the heat or high voltage. Who knew?

You'll see a basic schematic below. Super easy. And you'll see the "trick" right away. The signal goes thru the heater. Yep, right thru the heater. That must be what gives it the tube signature. You do need to connect the cathode to the input side of the heater and the anode to the output side (see diagram) to get the full effect. It's works OK without this, but much better with, tho I'll be darned if I know why. Also note that the grid is tied to ground via a 100K resistor. Changing the value of the resistor will change the harmonics and the sound. So you could put a 100K pot in there and tune it to your taste. The tuning effect is rather subtle, but it works. 100K worked for me.

So there you have it. It's super easy to add tube sound to any line level signal. And easy to experiment with different tubes for different effects. On the pentodes and tetrodes I tied the screens to the grid resistor, this seems to work best. Leaving them open gave too much hum. Signal loss is about 2-3dB, so no big deal.

So grab a tube or 2 from the junk box and have at it! Let me know what you think. It's a very surprising circuit. And it does not even need a power supply. (Just be sure the heater is not burned out)
Click to expand...

I have done the same thing with a simple PVC pipe.
 
#29
Now just package it up with some nicely made cable and you have a viable high end interconnect for which you can charge thousands of dollars. 😛😛

This is kind of like a certain cable company that puts magic metal boxes on one end of some of their more expensive interconnects.

This brand's marketing claims often read like an April Fool's day hoax.

This brand sells cables in every big box electronic store at 5 - 10X the cost of a functionally equivalent cable purchased on line.

This brand litigates at the drop of a hat over many things.

The name of this company shall not be not mentioned to avoid a potential lawsuit.. 🙄
 
#33
Hi,

panomaniac said:
Now here is a very nifty circuit that I came up with by accident, just trying things out.
Click to expand...

I am sorry, but you cannot use this circuit. You must disassemble it immediatly.

It is patented by Koshka Inc. and was used in Koshka Inc's Audio Demoronisator AD-1.

An externally hosted image should be here but it was not working when we last tested it.


Koshka Inc. requires ANYONE implementing this circuit (even for personal use) to pay a licence fee of 100,000 US Dollar per unit manufactured. You may better buy one Unit of the AD-1, it is available for the very reasonable of 75,000 USD from Koshka Inc, but I have an excellent condition unit at hand which I may be willing to part with for the bargain price of 50,000 USD.

Ciao T

(PS, the above is of course completely satirical, in case you did not notice. Koshka is a rather ill tempered feline who owns a fairly famous poster on audiophile forums and a rather amazing hornloaded, SET Amplifier driven Ultra Fidelity System)
 
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#34

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