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Main :: DT50/DT25

DT25 preamp tube
by gareee on 2011-12-28 09:07:53.4750


Does the DT25 use the 12AX7 in the preamp stage? I'm having difficulty understanding how it is put together.  If it does, then I'm unsure how the the HD500 preamp models fit into the picture.  On the DT50 specs, it mentions that the 12AX7 is in the preamp stage, but it doesn't say this for the DT25.  Is it different? How? Is the preamp completely modeled, so that any distortion will be modeled?

Thanks again.

Re: DT25 preamp tube
by DarthHollis on 2011-12-28 10:05:49.0950

This should help explain:


Re: DT25 preamp tube
by gareee on 2011-12-28 13:59:06.2220

I'm not understanding this.  Is the 12AX7 preamp tube not part of the preamp, since the preamp is modeled?

Is the distortion all based on modeling? In the models on the edit software, you create the distortion using the preamps. I assume that any distortion that is created comes from this modeling stage - then is fed through some  tubes in difference configurations based on the topology setting.  So  this topology thing is just a tube circuit to feed the preamp models through, right? As in, it's not creating the distortion, just colouring it in a consistent pattern for each topology, colouring clean sounds and distorted sounds in the same way.

Strange beast, this is.  I'm planning on getting one, but would like to understand it before making the purchase.  It would be nice if there were a way to generate tube-based distortion.

Re: DT25 preamp tube
by DarthHollis on 2011-12-29 05:33:22.3510

Seems like you are understanding it correctly.  Marshall has a series of amps that do the same thing but all in the amp itself.  It's called the JMD series:

They have finally discovered that they can better model the preamp section of an amp than the power amp section.

Anyway, I have been using the POD HD 500 with a DT-50 head and a Line 6 4x12 with V30s for a few months now and I love it.  I used to have the HD147 (all digital with a solid state power amp) and it was OK but nothing like the DT-50.  The power amp section really makes a difference and the POD HD technology is very good, much better than the last generation.

The only thing I can say is to try it out for yourself.  If there is no store in your area ask for members of this forum in your area that have one.  I would let people test out my set up if they were interested.

Re: DT25 preamp tube
by Line6Don on 2012-01-04 09:59:42.3630

+1 to hollis1003.

The answers are on the threads that he provided to you above:

"The two 12AX7/ECC83  tubes are not pre-amp tubes in the traditional sense.  They are both part of the power amp section. 

One boosts the overall level of the pre-amp output to drive the EL34's and the other is used as an inverter."

Therefore the DT series amp include 4 different preamp models to choose from, when using in combination with one our HD series POD's, more preamp models from the POD can be used in place of the 4 internal preamp models of the DT.

The information above may not be current, and you should direct questions to the current forum or review the manual.