Modding a Behringer T1953

elektro80 · Posted: Fri Apr 13, 2007 10:15 am Post subject: Modding a Behringer T1953

A friend brought one over to me some days ago. He wanted me to have a look inside and see if I could mod it. Basically what he said he wanted was new and better tubes.

However, taking a look at the boards and listening to the sound of this thing, obviously this is simply a cheap op-amp based pre-amp design with a tube distortion circuit thrown in. Behringer is using the NJM4580 in this one. These are prettty bad but they are really cheap too. Overalll the T1953 isn´t built too badly at all. You can get these for nothing these days. Replacing the NJM4580s with something bettter might turn this thing into a gem. Replacing the tubes might of course change the sound of it, but the real problem is the NJM4580.

Posted Image, might have been reduced in size. Click Image to view fullscreen.

Posted Image, might have been reduced in size. Click Image to view fullscreen.

Any suggestions re better opamps? Which to choose? I guess there must be some drop in compatible ones out there.

Uh.. and the shit is all SMD. I haven´t really messed with SMD before. Shocked

I always liked my opamps in huge fancy coloured sockets Shocked

elektro80 · Posted: Fri Apr 13, 2007 10:19 am Post subject:

What I do suspect is that replacing the opamps with better ones might turn this into something really useful. There are other mods to be done here too but those won´t make much sense right now.

elektro80 · Posted: Fri Apr 13, 2007 10:36 am Post subject:

My ears are telling me that the UTC thingie.. supposed to add "tube warmth" sounds nothing like how a classic tube design would. Instead it adds some grit which isn´t really very nice at all. Small amounts of grit kinda works like an exciter of sorts, but actually marketing this device as a tube pre-amp is a joke.

Any suggestion´s for which circle of Hell Mr. Behringer will end up in?
This one?

blue hell · Posted: Fri Apr 13, 2007 11:46 am Post subject:

Rob told me the other day that someone had found out, like the vagueness already Very Happy

, that lowering the annode voltage of tubes would make them sound more tube like. What happens of course is that you add distortion that does not belong in a tube circuit.

Did you find a high voltage transformer at all ? I suspect the tube look of the device (nice knobs & meters) to be better than the tube circuit itself. I'm not sure what sound your 'custome' is after, should it be cleaner or dirtier ?

For dirtier maybe try to make the tube power supply worse, for cleaner rip out the tube stuff.

Just a wild guess of course Laughing

elektro80 · Posted: Fri Apr 13, 2007 12:01 pm Post subject:

Jan, obviously my client got this thing because it was a real tube preamp. He always reads all these low end brit music gear rags. I hope he doesn´t read this. Shocked

Anyways, he came up with this thing because some pro music buddy had told him about the vaccum in the tubes is more friendly to the audio than solid state components.. Imagine pushing audio through something solid? Not good! So.. the vaccum offers the least resistance. Shocked

But.. there is more to come: The vaccum also adds an airy quality. Shocked

Enter the T1953.
He and his friends are always buying all sorts of different tubes for the guitar amps. Some tubes will play better with Boss effects and other tubes will sound better combined with Electri-harmonix boxes. Shocked

They are always buying special batches of 9 volt batteries for their Boss pedals.
He was actually pleased with his T1953, because since it was a modern clone of a classic design it HAD to be good.

I listened to it. I opened it and explained to him how the unit works.
This is simply a basic op-amp based preamp. Then some crackhead in the marketing department must have demanded that they added some tube warmth. The circuit is simply an extra distorsion effect.

elektro80 · Posted: Fri Apr 13, 2007 12:16 pm Post subject:

Unless one intends to mod this thing, there is simply no sane reason for buying it new. A secondhand one will be insanely cheap and thus it gives some serious bang for the bucks. The unit isn´t useless and not all bad, but the marketing is all wrong.

A much hated unit ( because it lacks all the great Behringer features Shocked

) is the excellent and cheap M-Audio DPM3. This one is actually pretty OK. I see people are selling these in order to invest in gear like the T1953. Shocked

http://www.m-audio.com/products/en_us/DMP3-main.html

elektro80 · Posted: Fri Apr 13, 2007 12:23 pm Post subject:

HEY!!!!!!!

I googled and found THIS.

blue hell · Posted: Fri Apr 13, 2007 12:34 pm Post subject:

blue hell · Posted: Fri Apr 13, 2007 12:36 pm Post subject:

v-un-v · Posted: Fri Apr 13, 2007 1:06 pm Post subject:

Very interesting stuff Stein- especially the link Very Happy

I've got a Mic-100 valve DI box here, which I suppose is a single channel version of the T1953 without the fancy VU's on the front panel? It's funny because it states- I guess as a selling point that it includes 4580 op-amps. I presume it's playing on that shampoo idea, with the ads that say "Pro-vitamin XYZ" which no one really knows what the hell this 'vitamin' is so good for? Confused

EdisonRex · Posted: Fri Apr 13, 2007 1:22 pm Post subject:

v-un-v · Posted: Fri Apr 13, 2007 1:23 pm Post subject:

The moderator on that forum chimes in with this though, and I think he has a very valuble and highly important point;

v-un-v · Posted: Fri Apr 13, 2007 1:27 pm Post subject:

elektro80 · Posted: Fri Apr 13, 2007 1:33 pm Post subject:

Yup. The work and the SMD shit is annoying Laughing

I dunno. I better come up with the name of some local repair shop that will willingly go tube hunting for that "client" of mine. Replacing the opamps, killing the tube circuit completely and adding fat and fancy transformers is the only sensible I can come up with. I will either do something that will make some kind of difference or not to the job at all.

No matter how it looks.. the T1953 is really a cheap and fairly decent solid state 1U rack unit.. Laughing

v-un-v · Posted: Fri Apr 13, 2007 1:36 pm Post subject:

EdisonRex · Posted: Fri Apr 13, 2007 1:40 pm Post subject:

elektro80 · Posted: Fri Apr 13, 2007 1:43 pm Post subject:

But... did I say fairly decent? The truth is that the circuit looks like something out of some standard design example leaflet.. built with the cheapest opamps they could get. If Behringer had kept the 1U formfactor, slammed some inexpensive but OK transformers in there.. better opamps.. a slightly better cabling job.. Rolling Eyes

elektro80 · Posted: Fri Apr 13, 2007 1:47 pm Post subject:

It got stellar reviews? Really? Shocked

But... this is impossible!

The box is nice though. I might want to pick up dead units in order to use the cabinet.

elektro80 · Posted: Fri Apr 13, 2007 1:49 pm Post subject:

It got good reviews? But any seasoned reviewer will "get" what this is instantly. And they wil also have heard all sorts of preamps already. Shocked

Let´s take a look at how a tube preamp really looks like:

The Gyraf G9 DIY project

EdisonRex · Posted: Fri Apr 13, 2007 1:52 pm Post subject:

yeah, it did. I've been reading up since this topic started. I knew nothing about it, not being in the market for a cheap "valve" preamp.

I'm sitting here reading this stuff and going "huh?" so it's good to read some actual analysis. I might dissect this UB502 here just to see what's in it. I bet I know...

elektro80 · Posted: Fri Apr 13, 2007 1:58 pm Post subject:

BTW....

I have posted this before... but...

Posted Image, might have been reduced in size. Click Image to view fullscreen.

EdisonRex · Posted: Fri Apr 13, 2007 2:01 pm Post subject:

*snort*

oh dear. Eric Barbour would have a fit. Razz

v-un-v · Posted: Fri Apr 13, 2007 2:03 pm Post subject:

Yeah but have you actually seen this tube glow without the LED's? It's pretty dull. Groovy lights in the dark look cool! Laughing

elektro80 · Posted: Fri Apr 13, 2007 2:05 pm Post subject:

v-un-v · Posted: Fri Apr 13, 2007 2:14 pm Post subject: