Rolling back JTV 2.23 firmware to 1.71

[brettwade]

Hi all, Can I clone a JVT which is rolled back to 1.71 to another JTV on firmware 2.23 and have all the patches on the jtv using firmware 1.71 plus the 1.71 firmware itself overwrite the JTV on 2.23.? My hope is to have 2 jtv's both running on firmware 1.71  I was originally going to use the same method I used getting my first JTV back to firmware 1.71 which was to use monkey to roll back the firmware, but I cannot get monkey to run on the older computer I used before, so I'm hoping that cloning the instrument might work...thanks anyone for your help...Brett

[silverhead]

Have you tried using Line 6 Central instead of Monkey to roll back the firmware?

[brettwade]

On 3/8/2025 at 4:34 AM, silverhead said:

Have you tried using Line 6 Central instead of Monkey to roll back the firmware?

Thanks so much for that...I didn't know it existed. Any replies I have gotten on this subject have all suggested running an old computer so I could roll back the firmware using monkey/workbench. I read the description on Line 6 Central and am I correct in understanding that implementing that method bypasses all the older equipment? (except perhaps the computer to run workbench) If that's the case, great! Thanks again for this info. I'm so surprised it was never suggested before, either in the forum or in general google searches...much appreciated....Brett

[silverhead]

I’m not certain it will work. Just suggesting that it’s worth a try. Can’t do any harm. 

[brettwade]

On 3/8/2025 at 7:05 PM, silverhead said:

I’m not certain it will work. Just suggesting that it’s worth a try. Can’t do any harm. 

Ya I know, I don't hold you to it, it's just nice having this option. You wouldn't by any chance know when the major acoustic changes happened with variax? I'm rolling back to firmware 1.71 mainly because the acoustics in 2.23 don't work as well in the ensembles I play in, but was there some acoustic versions in between those two...like somewhere around 1.80 or 1.90? thanks man...Brett

[silverhead]

The acoustic models changed in v1.8

[carlc]

On 3/10/2025 at 1:52 AM, brettwade said:

Ya I know, I don't hold you to it, it's just nice having this option. You wouldn't by any chance know when the major acoustic changes happened with variax? I'm rolling back to firmware 1.71 mainly because the acoustics in 2.23 don't work as well in the ensembles I play in, but was there some acoustic versions in between those two...like somewhere around 1.80 or 1.90? thanks man...Brett

 

On 3/10/2025 at 4:50 AM, silverhead said:

The acoustic models changed in v1.8

 

I am curious about the difference in acoustic guitar models.  I see the firmware release notes on the Line 6 website (under Downloads, select James Tyler Variax + Firmware).  The v1.8 firmware was released back in 2012, long before I purchased my JTV-69.  The release notes imply that the newer models are much better (see snippet below), but some may prefer the original models.  The release notes also imply that if you saved presets with the older models, you can reload them onto the Variax using Workbench HD.  Can someone share what is different about the older acoustic models?  Also, would anyone be willing to share a few presets on CustomTone using the older acoustic models?  :-) 

 

Quote

 

This free v1.8 update gives all James Tyler® Variax® modeling guitars five next-generation acoustic guitar models based on* celebrated 6- and 12-string acoustics from Martin®, Guild® and Gibson®. If you play your JTV with a POD® HD500 or POD® HD Pro multi-effect processor, the v1.8 update also includes enhanced functionality to make your JTV/POD HD experience even more intuitive and powerful.

 

Next-generation Models:

• New modeling technology. Our new breakthrough acoustic guitar modeling technology gives the five models breathtaking depth and detail, capturing the subtle nuances of string vibration through the soundboard and the tonewoods of the original modeled guitar body.
• Five updated models. The updated models are based on* the Martin® D28, Martin® D12-28, Martin® 0-18, Guild® 12 String, and Gibson® J200 acoustic guitars.

Note: If you've loaded your guitar with custom models and would like to retain your current custom banks and/or custom models, please sync with Variax Workbench and save your custom model set. You will be able to re-load your models from Workbench after you've complete the update.

 

 

 

[psarkissian]

Do not use v1.8x,... there was glitch in it where, if you tried to update later from there, you have a 50/50 chance

of locking up the program board (bricking it), making it non functional.

 

At that point, I would have less than a 50/50 chance of bringing that board back to life with the tools I have here at Line 6. 

 

So Do not use v1.8x. 

 

 

[carlc]

On 2/23/2026 at 7:47 AM, psarkissian said:

Do not use v1.8x,... there was glitch in it where, if you tried to update later from there, you have a 50/50 chance

of locking up the program board (bricking it), making it non functional.

 

At that point, I would have less than a 50/50 chance of bringing that board back to life with the tools I have here at Line 6. 

 

So Do not use v1.8x. 

 

 

Got it, thanks!  I appreciate the warning; I definitely do not want to brick my Variax. 

 

Of course, if I wanted to hear the older acoustic guitar models, I would need to revert to a firmware version PRIOR to v1.8, so likely v1.7.1.  It is probably more trouble that it is worth. I was simply curious how the older models sounded. 

 

Another option could be to load an individual preset.  I believe older presets can be loaded on a Variax with the most recent firmware (maybe?) and it would utilize the older model(s).  I don't see any presets that old on CustomTone, so I think I'm out of luck there.  If I ever decide to revert my firmware, I'll be sure to capture all of the presets as .whd files.

[silverhead]

On 2/24/2026 at 4:45 AM, carlc said:

..

 

Another option could be to load an individual preset.  I believe older presets can be loaded on a Variax with the most recent firmware (maybe?) and it would utilize the older model(s).  I don't see any presets that old on CustomTone, so I think I'm out of luck there.  If I ever decide to revert my firmware, I'll be sure to capture all of the presets as .whd files.

I don’t think that will work. A preset does not generate or include audio. It contains a data specification of all the parameters required (e.g. body, pickups, tuning, etc.) for the firmware to generate the audio associated with that specification using the DSP included in the firmware. An older preset will not generate audio using the older firmware/DSP; it will use the current DSP (modeling algorithms) loaded with the current firmware to generate the audio associated with the old specification.
 

In other words, a v1.71 preset specifying an acoustic model that is loaded into v2.x firmware will use the v2.x acoustic modeling, not the v1.71 modeling.