Boss Katana Technology

Started by coyote1411, August 30, 2017, 11:57:12 PM

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coyote1411

Hi,

I would like to know more about the technology behind the boss katana. Could anybody help me? For what I've read, there are a lot of different opinions and BOSS is not helping in making things clearer. I have the boss katana 100W head and I really like it.

For example, I heard that it's an discrete-analog preamp circuitry (what does it mean? FPGA?) and a fully analog A/B poweramp (is it really like this? I thought they use some kind of DSP to model the poweramp section of a tube amp).
Some says it has the tube logic design, others say it is COSM. May it be tube logic for the preamp simulation and COSM for the effects? Even if it was, what these technology really mean is not clear to me :)
Some also said that is an analog amp, but if you are able to recall sneaky amps and change the default ones via software, it  means that there is a certain level of modeling or at least some parameter to change for the preamp stage...

I am a curious Engineer (even not in this field) and having some insight on this amp will make me like it even more. I also think that for the price, there must not be very powerful DSP processors or even super complex algorithms.

One of the sources that stimulates my research is this article: http://www.mitpressjournals.org/doi/pdf/10.1162/comj.2009.33.2.85
I wonder if the Katana may fall in one of the cited categories or is it a beast of its own.
My feeling is for the FPGA-like thing for the preamp and the analog + some DSP tweaking/filtering for the poweramp.

Cheers
Fabio

admin

#1
It's typical Roland/ Boss latest gen design but with a discrete multi FET input stage with analog filters , then a dual port wide dynamic range 24 bit A/D> DSP> 24 bit D/A , but the special Tone magic occurs with the Katana Class AB power Amp voiced to respond like a 60's UK Amp with EL-34 tubes

Add (USB AUDIO ) D/A , A/D , and FX loop A/D , D/A
Review the internal pics thread

https://www.vguitarforums.com/smf/index.php?topic=19475.0

coyote1411

That's really interesting. Thank you! Just two noob concerns then...;)

The different kind of pre-amps (clean, crunch,lead, brown) are generated in the discrete multi FET input stages and the DSP is just for the effects section?
And for the voicing of the power amp you mentioned,  i guess it is fully analog?




Smash

So it's not a class D but A/B analog consuming 77 watts and producing a claimed 100?  ???

gumtown

Quote from: coyote1411 on August 31, 2017, 03:24:51 AM
That's really interesting. Thank you! Just two noob concerns then...;)

The different kind of pre-amps (clean, crunch,lead, brown) are generated in the discrete multi FET input stages and the DSP is just for the effects section?
Everything is generated by the DSP, there are no analog preamps, the DSP has been matched to an analog FET gain stage before the power amp.

Quote from: coyote1411 on August 31, 2017, 03:24:51 AM
And for the voicing of the power amp you mentioned,  i guess it is fully analog?
Yes
Free "GR-55 FloorBoard" editor software from https://sourceforge.net/projects/grfloorboard/

Elantric

#5
QuoteSo it's not a class D but A/B analog consuming 77 watts and producing a claimed 100?  ???


If the Katana high power setting was any louder  I could not use it as it would be too loud for my band

Suggest go actually play one

the power amp is a proprietary Boss design
https://www.thegearpage.net/board/index.php?threads/boss-katana-amplifiers.1744135/page-523#post-24778627

Smash

I don't doubt it's loud! To be fair the thread is on technology and ive noticed a trend in newest audio tech apparently giving greater output power c/w consumption.

Obviously they can't create energy so I wonder if the output measurement has changed in some way - that maybe it's now based on SPL. They don't specify RMS.

Just curious to understand what's happening or changed?

Mety

#7
Hi there new member here!
Long post coming up... ;D

Like the OP, I'm also very interested to discover more about this technology. I've recently bought a Katana head and I'm so impressed with its sound and feel! I can now leave my heavy valve amps at home and ditch the helix that I've been struggling with. The katana has really made a huge impression on me and I'm loving it!

The only thing is - I'm using the hidden or "sneaky" 1959 I + II almost exclusively and I emailed Boss UK with a question about the similarity between the hidden amps and my GT-100 amps. Their answer wasn't that clear but here it is:

However, I am afraid that we are not involved in development of the "Hidden Amp" and also that is unsupported and not guaranteed by Roland/BOSS.

In addition, we would like to clarify that KTN amps have totally original amp types and hardware structure which were newly developed and tuned for it and are inherited from WAZA AMP DNA. This is not just diverted from other products. Again, we didn't develop Hidden Amp and when Hidden Amp is recalled, the sound was not tuned and optimized for KTN amp.


So, it seems they (Boss/Roland?) were not involved in the development of the hidden amps, which are not tuned or optimised for the Katana, but furthermore they did not come from other products? So how did they come to be in there then? ;) I love the 1959 I +II and would hate to lose it in future updates.

If any further insight into this comes to light, I'd be very interested to hear it!

admin

#8
Start here:
https://www.vguitarforums.com/smf/index.php?topic=20693.msg148992#msg148992

and observe the dates timestamp  of the posts for the evolution of Katana "Sneaky Amps"

these are officially NOT Recognized  / nor supported by Roland / Boss - and its very likely the next Katana Firmware update may "spoil the fun" and break access to the hidden Katana sneaky amps

review the "Katana Sneaky" amp team -
https://www.vguitarforums.com/smf/index.php?topic=20693.msg148992#msg148992

Gumtown is the same person that has helped Roland sell tens of thousands of GR-55's  - thanks to his crucial "GR-55 Floorboard Editor" - and he has been integral on making the discovery of the hidden amps inside the Katana DSP code , and sharing his valuable Katana Floorboard Editor to the world

its not actually free - but shareware

Mety

Wow, so much to read!
I remember Gumtown from the GT forums, many thanks to him for the floorboard!
Thanks for the help admsustainiac . :D

I really think this amp is something special...

admin

#10
Quote from: Mety on September 19, 2017, 02:43:28 PM
Wow, so much to read!
I remember Gumtown from the GT forums, many thanks to him for the floorboard!
Thanks for the help admsustainiac . :D

I really think this amp is something special...

Indeed - many others do too!





https://www.thegearpage.net/board/index.php?threads/boss-katana-amplifiers.1744135/page-535

Beanow

Quote from: Mety on September 19, 2017, 02:13:46 PM
However, I am afraid that we are not involved in development of the "Hidden Amp" and also that is unsupported and not guaranteed by Roland/BOSS.

In addition, we would like to clarify that KTN amps have totally original amp types and hardware structure which were newly developed and tuned for it and are inherited from WAZA AMP DNA. This is not just diverted from other products. Again, we didn't develop Hidden Amp and when Hidden Amp is recalled, the sound was not tuned and optimized for KTN amp.


Hahaha, loving the marketing answer. Deny EVERYTHING! It's a €300 WAZA!

The way the firmware works is extremely similar to the GT-100 and GT-001 official documentation.
All the names that you see in the Floorboard editor such as the Marshalls were originally taken from the GT-100 documentation as well.
Full list here https://github.com/katana-dev/docs/blob/master/data/sneaky-amps-1.0.2.csv

When we first cycled through these new amps there was no way to know if they would match with the GT-100 names.
So it was a matter of trying them all out, looking them up and checking, "sounds pretty marshall-ish" and work through all of them.
And they all match their alleged names far too well to be just a coincidence.
The same applies to the sneaky effects in there, like the tera echo. Every parameter matches the GT-100 spec and sounds like the documented effect.

Lastly the DSP chips they're using are also chips that were seen before in their other modeling products, like the GT-100.

So all of those indicators combined, the consensus theory is these hidden amps and effects are leftovers from the GT-100 or GT-001 firmware that they used as a starting point for developing the Katana with and haven't spent the time to remove them from the firmware more thoroughly. In fact, when Boss replies with "...when Hidden Amp is recalled, the sound was not tuned and optimized for KTN amp." it just makes it more likely they are practically unchanged from the GT-100 baseline firmware.

coyote1411

Very nice and informative discussion! Thanks for your support!

bowtomecha

Sorry to revive an old thread, but I haven't found any literature specifically stating that the Katana uses MDP. I've been assuming that since the 2.0 update, the added Tera Echo strongly suggests that it does since the original pedal and the update to the GT100 are both shown as using MDP to create the effect. The Katana is supposed to be loosely based on the GT100 (sneaky amps indicated that) so I'm wondering if there is anything else official or implied, that shows that the Katana can or uses MDP or COSM (differences?) to generate effects.

I'm mostly asking because if it can do so, one day it will be ripe for non official firmware hacks that include GT100 abilities like Adaptive Distortion or parallel stacks, or mimicking the boss Multiband compression pedal. I really feel that this amp was meant to be a pleasantly voiced jack of all trades when it has the capability to be a very focused amp where the processing is set to enhance the tone and dynamics. One day I hope somebody comes out with a hacked firmware that streamlines and enhances the amp as it ages.

sixeight

#14
Quote from: Bowtomecha on November 01, 2018, 02:26:17 PM
Sorry to revive an old thread, but I haven't found any literature specifically stating that the Katana uses MDP. I've been assuming that since the 2.0 update, the added Tera Echo strongly suggests that it does since the original pedal and the update to the GT100 are both shown as using MDP to create the effect. The Katana is supposed to be loosely based on the GT100 (sneaky amps indicated that) so I'm wondering if there is anything else official or implied, that shows that the Katana can or uses MDP or COSM (differences?) to generate effects.

COSM and MDP are just names for the technology and both are moving targets. COSM has developed and changed over the years. Afaik the Katana firmware is developed from the GT-100, which is COSM. But the new GT1000 uses MDP, which is based on the Katana amp modeling.

Quote
I'm mostly asking because if it can do so, one day it will be ripe for non official firmware hacks that include GT100 abilities like Adaptive Distortion or parallel stacks, or mimicking the boss Multiband compression pedal. I really feel that this amp was meant to be a pleasantly voiced jack of all trades when it has the capability to be a very focused amp where the processing is set to enhance the tone and dynamics. One day I hope somebody comes out with a hacked firmware that streamlines and enhances the amp as it ages.

Hacking firmware is very unlikely. The sneaky amps are not a firmware hack. Roland firmware is closed, and no one can change it.

The sneaky amps are available because sonebody changed the product id of GT-100 sysex messages to the Katana's product id and found to their suprise that the Katana responded.

admin

#15
QuoteCOSM and MDP are just names for the technology and both are moving targets. COSM has developed and changed over the years. Afaik the Katana firmware is developed from the GT-100, which is COSM. But the new GT1000 uses MDP, which is based on the Katana amp modeling.

Agreed they are just marketing names  - at the end of the day its DSP code

refer to the Roland Boss Glossary

COSM
https://www.sweetwater.com/insync/cosm/
Abbreviation for Composite Object Sound Modeling. COSM is a powerful modeling technology that Roland premiered in 1995 with the VG-8 V Guitar System, and continues in the newer VG-99 system and GT-100. It enables guitarists to emulate a range of classic and modern guitars, amps, cabinets, and microphones, plus it can produce "futuristic" synth-like tones. Today COSM can be found in keyboards, digital recorders, mixers, etc. It can model rotary effects, different speaker colorations, and can even approximate expensive microphones using just an ordinary dynamic mic. Its name comes from "composite object" because its core function revolves around breaking audio producing or reproducing devices down to their component parts and creating a set of instructions to emulate how these various parts interact with each other to produce a new composite that can be dynamically controlled. Of course, that's what all modeling is, but Roland coined this name to call attention to it.

AIRD :
https://www.bossus.com/blog/2018/04/19/gt-1000-guitar-effects-processor-now-available/#more-15393
Next-Level Performance with AIRD
The GT-1000 debuts BOSS's breakthrough AIRD (Augmented Impulse Response Dynamics) technology, bringing a new level of musical response and flexibility to digital guitar processors. Based on the comprehensive Tube Logic concept behind the acclaimed Katana, Waza, and Blues Cube amplifiers, AIRD is a complete interactive system that provides optimum performance in every application.



MDP
https://www.boss.info/us/promos/mdp_deep_dive/
With its intelligent processing approach, MDP delivers complex results that are simply not possible with conventional technologies. But this would mean nothing if those results weren't musical, natural, and inspiring to play. To this end, the intelligence in MDP processing is not simply the result of powerful DSP and advanced algorithms; it's intelligence that's guided by the massive experience, knowledge, and unwavering dedication of the engineers at BOSS, as well as the input of the world's greatest guitarists. With this powerful fusion of technology, craftsmanship, and know-how, MDP enables you to express your personal guitar voice like never before.


TUBE LOGIC
https://www.roland.com/global/promos/tube_logic/
With the innovative Tube Logic design philosophy that's at the heart of the Blues Cube series, we've nailed everything that players love about the classic tweed-era tube amps. Not just the sound character, but the organic feel and response as well—in short, every nuance that makes an amp a real musical instrument, one that inspires you and makes you feel great every time you plug in to play.

Reading all the creative descriptions above reminds me how little things have changed in  guitar effects description creative writing style


bowtomecha

So the Katana is technically mdp then?

admin

#17
It has an analog FET based input buffer preamp prior to the input stage 24 bit A/D which is configured to support widest dynamic range (  Fractal /Vetta style feeding both left & right A/D input with different gain sensitivity ) this A/D feeds the one  DSP (same type as a GT-100) .

Another separate A/D is used for FX Return. 

Separate 24 bit DACS  are employed for FX Send , Line Out, and final output DAC which feeds a custom Roland /Boss Designed Class AB power amp based on an ST Micro TDA7293V  which feeds the speaker.
http://www.st.com/en/audio-ics/tda7293.html


The Katana  Head employs a dedicated  power tap from the power amp  to attenuate it down to 30 watts for the internal 5 inch speaker

Boss Katana Amp - Inside View
https://www.vguitarforums.com/smf/index.php?topic=19475.msg138982#msg138982

sixeight

Quote from: Bowtomecha on November 03, 2018, 01:35:15 PM
So the Katana is technically mdp then?

The term MDP I and AIRD s used by Boss since the GT1000. The Katana is developed prior to the GT1000.

But nobody outside Roland knows exactly what is going on under the hood. My guess is Katana uses COSM voiced to the Katana hardware. And the GT1000 uses new amp modeling technology and existing fx technology.

Burr the difference between AIRD and MDP is not clear to me

gumtown

The Katana is a 2016~2017 period of "Boss modelling DSP technology", any advertising hype is meaningless except to the Roland/Boss promotions department.
It started in 1995 as COSM and has been a slow progression of improvements until the last 3 years, the COSM brand has been dropped,
and some research done to see where Boss sits with the other brands, and a bit of catch up with the GT-1000 by adding some basic Impulse Response stuff and calling it "AIRD".
Free "GR-55 FloorBoard" editor software from https://sourceforge.net/projects/grfloorboard/