Helix and DT50 "Hidden" Parameters and DT/SV/SS amp comparison

[roscoe5]

Is anyone tweaking the DT50 "hidden" parameters 12AX7 boost, phase inverter B+ voltage, or feedback capacitor type for Helix?

I'm just wondering if these affect Helix's signal path.

[roscoe5]

I finally got around to really digging into my DT50 head.

 

First off, I didn't realize Line 6 didn't have a DT Editor and that I was previously editing my old DT through HD500 Edit, duh.  Thanks to a ColonalForbin post, I found the independent dev app.

 

http://rome2.github.io/dtedit/

 

Second, I didn't realize you have to enable MIDI Thru in Helix global settings to update the DT amps and send DT Edit commands through USB>Helix>DT...duh #2.

 

I found the DT hidden MIDI parameters and Helix really do make a difference.  Although I can't say I would even miss them or know what I was missing if they weren't there, like in the DT25.  

 

• 12AX7 Boost really does drive the power tubes harder, a bit more power tube distortion.  Pretty cool to tie this to a MIDI CC and footswitch as a solo boost.
• PIV B+ Voltage high/low is pretty subtle.  I noticed the biggest difference in Class A on the Vox type stuff.
• Feedback capacitor tight/loose feels about like switching in the Bold and Spongy switch on my Mesa amps.  Really impacts high gain palm muted and djent rhythms.

I successfully went XLR out DT50>Helix Mic In>2nd path cab/IR>Helix XLR out.  This really does give you the DT amp sound to FOH, especially when I used the IR's I created of my own cab. This does take up that 2nd path and limit the effects.  I haven't tried to use an XLR>1/4" into a send/return block, maybe that could buy back some space.

 

For the fun of it, I also tried out the DT cab and mic modeling on its XLR out. I almost laughed out loud at the sound of that compared to the HX Cabs in Helix, and of course IR's.  BUT there is a 57 off axis mic model in there...hint hint to Line 6 ;)

 

So 3 cables were required, 2x XLR & 1x MIDI.  Not too bad IMO.

 

Sadly, even with all of the DT50 topology, class, and hidden parameters...DT50 STILL sounds like I'm playing everything through an EL34 amp.  Brit and Chime Helix pre's sound great, Fender cleans are ok, but IMO the 6L6 uber high gain (pre)amps taste funny to me.

 

Now running those non-DT friendly high gain preamps into the 6L6 Spider Valve sounds fantastic!  I played around a bit using a Radial VT Headbone switcher with both the DT and SV amps using Helix Ext Amp as a "slingshot" remote controller for it.  That was very cool.  Definitely over-complicated and excessive as I would hate to have to take 2 heads to a gig and wire it all up.  But it was fun nonetheless.

 

IMO, the full Helix amp models into a solid state amp into my 2x12 V30 cab sounds better and is more versatile than Helix preamps into DT or SV into the same cab.  You really lose some of the character and tonality of the of the Helix full amp models, as well as the differences between them, when just using the pre's and DT & SV.

 

DT & SV definitely give you more tube amp feel.  But you are sort of limited to the sound of their respective power sections.   There is much less difference Helix preamp to preamp into DT or SV than Helix amps into SS power amp.  But Helix pres into DT/SV do sound great, just not necessarily true to the Helix full amp models.  

 

If you are traditionally a Marshall/Vox person, then DT50 is probably for you.  If you are normally Fender/Mesa, I would go with Spider Valve.  If you want the most versatility, then I would say solid state amp.

 

I have to say (while I watch for flying objects from the forum) from my experiences now with many different configurations that my order of preference for live use is

 

1. Helix amps>solid state amp>guitar cab
2. Helix preamps>Spider Valve HD100 effects return>guitar cab
3. Helix preamps>DT50 L6 Link>guitar cab
4. Helix preamps>Mesa Mark V effects return (or 4cm)>guitar cab
5. Helix amps+cabs/IR's>FRFR/PA/Monitor speakers

 

At this point, the Fryette Power Station is really intriguing to me as Helix into SS amp could use just a little tube amp feel.  It probably wouldnt make much difference to the crowd or the bandmates, but the player could probably feel it.  Fryette really sells the transparency and non-coloration of the thing. Videos of it with physical guitar heads AB'ing the head direct and then attenuated through the Power Station are impressive.  

 

Helix full amps into Spider Valve sound and feel great as it is pretty neutral, but there is still some slight coloration when compared to just the Helix amp models.  I can tell that I would really like this setup if it were truly transparent for the Helix amp models.  I would love for Line 6/Bogner to put out something similar/better specific to Helix.  My Helix backpack front compartment is begging for it ;)

[roscoe5]

Guys, I spent A LOT of time today with the DT50 amp and Helix trying to figure out what was up with the sound of the Helix preamps into the DT50. When I play the DT50 by itself, many of the HD-gen amps were actually sounding better than Helix pres into DT. Especially the 6L6 type high gain amps. There is just much more difference between native HD amp models in the DT than Helix pres into DT power amp. I also recalled that when I had a POD HD500x, I could use full amp models, not just preamps. Additionally, DT50 low volume mode lets the amp models contribute more since the power amp isn't driven as hard.

All of this made me suspect that full HD amp models, not just preamp models, are present and contributing to the overall sound in the DT50. I believe the DT/HD architecture was configured to control the amount of HD power amp modelling being passed through between normal and low volume modes. But it does sound to me that some level of HD power amp modelling is always present in the DT50.

I believe we lose some of the HD/DT hybrid power amp integration when using just Helix preamps with DT power amp sections. It is definitely apparent when comparing HD/DT50 amps to Helix pres/DT50 power amp into the same IR as I tested below.

I ran Guitar In>Helix Path A>Digital Out (L6 Link)>DT50 and DT50 XLR>Helix Mic Input>Path B>IR or Cab block>Headphones.  DT cab and mic models were off.

I set up three presets
1)Baseline Helix only: Helix Cali Rectifire Amp>Helix IR Block (no DT50 in the chain)
2)Helix +DT50: Helix Cali Rectifire Preamp>DT50 Class AB/IV/Pentode>Helix IR Block
3)DT50 only: DT50 Treadplate with matching topology>Helix IR

However, Helix full amps into DT50 are just too much right now. From this testing and experience I realize the challenge it must be to implement the same DT integration with Helix that was present with HD considering the different architecture. I don't think it's as simple as Helix preamps + DT power amp + topo control. If they are to truly make Helix/DT integration comparable to HD/DT, they will need to get some level of Helix power amp modeling through the DT architecture to the speakers for both full power and low power modes, along with topo control.

I've concluded that this is why Helix full amp models into the Spider Valve HD100 sound better to me than Helix pres into DT50. Also of note, I ran the SV HD100 send into Helix with the same IR.  The models in the SV are definitely full amp models and actually sound really good into an IR.  If you are missing the old Line 6 Insane and other models, you could certainly 4CM the SV and get them back in possibly better than original form to FOH with IR's.  This was even more reinforcement for my decision to use Helix full amp models into SV effects return.

 

I'm now feeling that some level of the Helix power amp model needs to blend with the DT tube section. I would bet that having a way to control the level/mix of Helix power amp modeling/influence going into SV, DT, or any other tube amp would really be amazing. I think DT/HD had this integrated in its design. Helix Pres are not enough to get the full Helix experience with SV, DT, or other tube amps.  Helix full amps are too much for DT, okay with SV, and might be great with the Fryette Power Station (most transparent).

I now totally sympathize with Line 6 not having this at launch. They are probably trying to nail it right. And I am very excited about the possibilities of Helix/DT. I would totally be okay with losing all of the DT HD modelling in a DT/Helix firmware update if that's what it takes to get Helix and DT on the same architecture to achieve full integration.