Why the AFxII has one dsp chip dedicated to amp(s)?

I think Cliff also stated in the past that if there were more Dsp's in the Axe it would actually increase the latency which I doubt most of us would like.
 
FractalAudio said:
One of the Axe-Fx's DSPs is more powerful than both DSPs combined in the Helix. Our tests show that the TigerSHARC DSP used in the Axe-Fx is over twice as fast as the DSP used in the Helix clock-for-clock . Now add that our DSP is clocked 50% higher the net power is about three times greater. So a single TigerSHARC is about 50% faster than both DSPs combined on the Helix. Yes, if we decided to use both DSPs for effects then you would be able to run more effects. 99% of our customers buy the unit for amp modeling so it doesn't make sense to invest the time and resources to making this possible.

Our algorithms are studio-quality and use more processing power than competing products. We've always been about quality over quantity. For example, our variable delay algorithm (chorus, flanger, etc.) uses poly-phase interpolation. EVERY competing product I have tested uses simple linear interpolation (or occasionally polynomial interpolation) which is far less computationally intensive but doesn't sound as good. This is demonstrable and measurable.

I highly doubt the Amplifire has two DSPs. My guess is that their claim of "blazing dual DSPs" is marketing for a DSP with two cores. My guess would be a Freescale Symphony (DSP5672x) DSP which is a dual-core DSP running at 200 or 250 MHz. While a dual-core DSP will be faster than the same DSP with a single core it will not have twice the power as the cores will share buses and contention for those buses will hamper peak throughput. The unit's capabilities are far below the Helix and Axe-Fx so I doubt their using a DSP with anywhere near the processing power. This is complete speculation though.
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When you say that your tests show that your processors are 2x as fast of the Helix, how were you able to test that? Did you use their same chips and your software on a dev kit? Did you boot your software on the Helix? Or did you extrapolate that info from data sheets? I just read that info on the Wiki and was curious.
 
DLC86 said:
I was looking at how other dual dsp modelers work (amplifire and helix in particular) and I asked myself this question. I think it's kind of a waste to have one of the two cpus dedicated to just this task in the case you want to use the axe as an effects only (or amp only) unit, you would have about twice the power if it had a more flexible architecture
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There isn't a single time where I've played the Axe and said to myself "You know, I really think that amp chip could be pulling more weight instead of just sitting there and sounding so freakin awesome."

I'm not belittling your initial question, I just wonder if it even matters?
 
Nothing wrong with a bit of intellectual curiosity. :)

Thanks, Cliff, for sharing specifics. I've worked for and bought products from a lot of companies that wouldn't give their customers the time of day without a credit card number. FAS is definitely a cut above.
 
Karl Houseknecht said:
There isn't a single time where I've played the Axe and said to myself "You know, I really think that amp chip could be pulling more weight instead of just sitting there and sounding so freakin awesome."
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Fortunately we don't share the same brain
;)
 
No.. no offense really.
I just meant that not all human beings think in the same way, fortunately for both of us and everyone else.
I replied in that sarcastic and maybe harsh way just because, in this 4 months old thread and generally in this forum, anyone's question that's led by curiosity is often interpreted and answered as a complaint by most of users.. because "the axe fx is the most awesomest musical instrument on earth, so shut up and play!"
I just don't like that attitude.
Sorry if that wasn't your intention
 
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I think its good to be curious too, and question why things are. That's what led Cliff to developing the axe in the first place isn't it?

Side story (ironic). There was a post from cliff about this but I can't find it:
Cliff traded in his real amp for a digital modeller that some music shop guy sold him on. The music shop guy (lets call him Norm) said "this is the best thing ever", (or something like that), then when Cliff took it home he couldn't make it sound like anything but balls after trying for days. He thought to himself - "surely, digital modelling can be better than this garbage" (or something like that). This is what drove him to develop the axe-fx. Does Norm realise that he, being ignorant and too accepting of mediocre digital modelling in general, is responsible for guitar amp modelling history? Where is Norm now? Selling hot dogs? Selling helix's? Unhappy because these 'fractals' are driving his sales down?

Cliff is like a bullet, but a bullet can't ignite without a gun. Norm is Cliff's gun. Norm is the key to the Axe-FX III. We must find him.

The moral: curious people, ignorant people, we all have a place in the world.
 
JJunkie said:
I think its good to be curious too, and question why things are. That's what led Cliff to developing the axe in the first place isn't it?

Side story (ironic). There was a post from cliff about this but I can't find it:
Cliff traded in his real amp for a digital modeller that some music shop guy sold him on. The music shop guy (lets call him Norm) said "this is the best thing ever", (or something like that), then when Cliff took it home he couldn't make it sound like anything but balls after trying for days. He thought to himself - "surely, digital modelling can be better than this garbage" (or something like that). This is what drove him to develop the axe-fx. Does Norm realise that he, being ignorant and too accepting of mediocre digital modelling in general, is responsible for guitar amp modelling history? Where is Norm now? Selling hot dogs? Selling helix's? Unhappy because these 'fractals' are driving his sales down?

Cliff is like a bullet, but a bullet can't ignite without a gun. Norm is Cliff's gun. Norm is the key to the Axe-FX III. We must find him.

The moral: curious people, ignorant people, we all have a place in the world.
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Great post! ;)
 
sam said:
When running two Amps it uses "normal" instead of "highest quality" amp modeling. This is because running 1 high quality amp uses more than 50% of DSP power on this chip.
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Are you talking about a single amp block or and amp *plus* cab using more than 50% of the DSP, i.e., are you saying that one single HQ amp block takes more than 50% of one Tiger Shark?
Because if that's true, it means that the AX8 (which has one DSP dedicate to amp modeling that are 3 times slower than the Tiger shark used in the Axe FX2) *must* be running its amp algorithm in "normal" modeling.
 
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