Let's continue with the Tube EQ thing!

[Learner]

Got some filter infos here, may be you can use the IC to drive the grid and compare with one on your link to see what you like better......


http://focus.ti.com/lit/an/sloa096/sloa096.pdf

 

[Rob Flinn]

Sounds like maybe you should clone a Klien & Hummel. I think Jakob has diagrams for this on the Gyraf page, but I`m not sure if they are the solid state or Valve version.

 

[TomWaterman]

Would something gyrator based be the kind of thing Jaakko?

I don't know of any but surely Jakob can assist...

I also don't know what I'm on about but IIRC gyrators can create the L (inductor) portion of RCL filter networks.

Could a passive EQ be designed with tube gyrators replacing the inductors and Jakobs SRPP tube gain stage???

I'm probably completely off the mark anyway but I remember being told about something similar with opamps anyway!

Tom

 

[Rob Flinn]

Somewhere in my archives I`ve got details of a valve based graphic eq that someone had posted a while back. He used valve based gyrators that were pretty similar to the info at Elliot sounds but with a valve.

I could probably find the article but I have no way of posting it at the moment because the internet connection on my home PC is completely buggered!

 

[gyraf]

This?
http://www.blaze.net.au/~sasami/synth/tube/vcf.html

Jakob E.

 

[Rob Flinn]

thats not the one I`m talking about. The guy made a stereo 7 band graphic. It used about 10 dual triodes.

 

[sismofyt]

That's the Audio Baton, we discussed it at RO :wink:

 

[sismofyt]

It looks damn cool though!

 

[Rob Flinn]

That Audio Baton is very similar to an eq my friend has, but I think has a different name. What I like about it is the way the pots turn a rod with a spiral stripe on it (bit like a barbers pole) & that is what gives you the graphical representation of the eq curve. The stripe moves up or down in a slot when the pot is turned.

My home PC is still knackered, but I will try to find the graphic eq article.

 

[ChumpitO]

Heres someones DIY tube EQ, whoops looked closer and it's passive.

http://www.robflinn.eurobell.co.uk/valveeq.htm

 

[Guest]

I found an article some time ago about Baxandall circuits that explained a midrange EQ. I normally use Baxandall for bass and treble control in guitar amp circuits so I was intrigueid by this idea. Anyway, I put it into my computer and ran some simulations but have not had the chance to build it yet. You can use tube, as is my prefference, or solid state for this circuit. I can dig up a schematic if anyone is interested.

 

[chriss]

Kubi,

the UE-1000 is just a follow-up of the UE-100 which actually IS tube-based, so it would be easier to just clone this one. Well forget the last words - I guess it is anything else but easy to clone these monsters! I have an UE-1000 that doesn't work and I wonder if I will be able to make it work ever again!?.... I opened it once, took a look and very fast closed it again.

Chris

 

[chriss]

Jaakko,

that sounds like the perfect solution to me. Would you also be so kind and take these grey units, saying 'v72' on the front? They just waste my space........

Kubi,

I wonder if it possible at all to build a Fairchild?!..

Chris

 

[thermionic]

I have a full manual / schematics for the UE100, but I do not have a scanner...

I can snail-post a photocopy to someone for scanning though, Jakob?

Justin

 

[Tungstengruvsten]

I'd say don't bother with the audio baton...had one for awhile and turned around and sold it again. Yeah it's neat looking etc but with no trannies in or out it's very picky about where you can use it...also the circuit doesn't really lend a sound of it's own, a character...

I was going to go so far as to replace all the tubes with 5751's and maybe redo the resistors but it just couldn't tip the scale of neat looking but useless

 

[ciminosound]

Does Rob Flinn actually know where we are? He was with us at RO...

Kev you should shoot a email to the Group DIY folks.....

 

[ciminosound]

DOOH!!!!! :!: