Promit
Inspired
I assume you don't mean the rebranded Panasonics :lol Leica's been all over the map lately. Imagine reselling HD500s with Fractal logos on them!Do you want an Olympus or a Leica. I'll take the Leica.
I assume you don't mean the rebranded Panasonics :lol Leica's been all over the map lately. Imagine reselling HD500s with Fractal logos on them!Do you want an Olympus or a Leica. I'll take the Leica.
No, but they can still pull the same weight as an 800Hp F1.
I get what you're saying, but it's still hard to grasp for a layman in microelectronics how the differences in processing power can be so huge depending on the purpose.
At one point in hardware evolution, we had 4Ghz single-core general-purpose CPUs before the trend for multi-cores started. It's like DSPs are living 15 years in the past.
No, but they can still pull the same weight as an 800Hp F1.
I get what you're saying, but it's still hard to grasp for a layman in microelectronics how the differences in processing power can be so huge depending on the purpose.
At one point in hardware evolution, we had 4Ghz single-core general-purpose CPUs before the trend for multi-cores started. It's like DSPs are living 15 years in the past.
Comparing Ghz is meaningless when comparing different classes of processors. It is simply the speed of clock that pushes the CPU. What matters is how much can be done within those clock cycles. DSP chips can perform certain types of operations by executing just a couple instructions vs. a traditional CPU which would have to perhaps iterate thousands of times over a more complex set of instructions. So while your 4Ghz CPU is spinning it's wheels doing that, the 500Mhz DSP has done dozens of other operations already.
The HP comparison is an interesting one. You say an F1 is 800HP. Well, there are trucks out there that are 800HP. Which is going to haul 10 tons of bricks faster? If HP were all that mattered, how come two vehicles with the same HP can't go the same speed? There are plenty of cars with less than 800HP that will outrun an F1.
How about we compare cylinders instead? A McLaren is a V12 so it should be faster than a V8 right? Nope. The Venom GT with a V8 has got 30mph on the McLaren.
The point is simply that there are different designs and there is no single factor that will give you an absolute performance indicator that transcends all uses.
Even comparing Ghz to Ghz for the same basic CPU model is not going to give you an indication of what system performance is like. A computer with a 3Ghz CPU will not perform 50% better than an otherwise identical computer with a 2Ghz CPU - you're still limited by the system bus, memory speed, GPU/display speed, etc.
Almost all cellphones use ARM CPUs which are RISC-based CPUs. Intel CPUs that you find in PCs and Macs are CISC-based CPUs. So can you really compare your A8 powered 1.4Ghz cellphone to your Intel Atom powered 1.6Ghz tablet?
Ok, so - I'm not a DSP programmer, but I've done enough systems work to have a general sense of what's going on. There are a few competing factors at play.
First off, there's nothing all that special in the SHARC instruction set. A modern x86 (or even ARM!) processor has many of the same instructions and can even do vector versions of those operations. But you have to look at it from the perspective of a total system design. This is a real time embedded system. You have an analog signal in and in most cases an analog signal out. That means A/D conversion, digital processing, and D/A conversion need to all be done at very tight latency requirements. The DSP chip is designed to get those signals into the chip, processed, and out again quickly. Its operations are focused around that purpose, and when coded properly you don't have to deal with pipeline stalls, cache misses, TLB faults, page faults, interrupts, or a mountain of other garbage that can get in the way of processing on a normal off the shelf computing platform. And while I haven't dug into it, I suspect that synchronization across two DSPs is dramatically easier and more reliable than synchronization of CPU cores.
Second, you have power and heat requirements. Those 4 GHz chips are also going to be dissipating 90W on their own, and there are other components required to complete the system. It takes heavy heat sinks and multiple fans to dissipate the heat being generated. Then there are the support components involved. You've seen the size and weight of a PC power supply, right? There are expensive VRM capacitors that pull down the +12V lines again to the 1.1V or so (at quite a few amps) that the CPU depends on. Sure, you can start scaling down the power requirements, but once you get down to levels that are appropriate for something like the 30W Axe Fx? All of a sudden you'll find that compute performance has gone to shit and is actually worse than those focused DSP chips. Mobile chips are powerful for their size, but there's a reason BIAS sounds like trash next to Axe or even an 11r.
Hell, think about the physical requirements. Have you ever had to sit in a room with rackmount servers? They're probably 20 dB louder than the grinding "loud" fan on an Axe Fx. Significant airflow is required, too. A sealed box like the Axe would never fly.
Another issue that probably doesn't apply to Axe but applies to a whole host of other applications where a DSP is used - reliability and robustness. They put these things in missiles, rockets, submarines, etc. The error rate on an Intel x86 chip (that is, computations that return invalid results) is going to be significantly higher even in normal use, and harsh environments will make things worse. General purpose platforms are not designed to sustain this type of abuse. An Intel chip lives on the ragged edge of its physical limits and those limits are easily disturbed. This is why you constantly hear news stories where space equipment, fighter jets, etc are being produced with processors that are 8+ years old. The simpler, older designs are required to provide sufficiently robust platforms, and often there's a ton of extra improvements made.
All that said, it's not immediately obvious to me why a TigerSHARC is so expensive or what makes it preferable to something like a TI C6000 DSP which is claiming comparable performance at a fraction of the price.
I love how this totally boring speculative discussion flame-fest was completely derailed into something informative and interesting about DSP and audio hardware architecture.
It's like this thread got reverse-trolled.
Modern Intel CPUs are incredibly powerful and can easily replace a TigerSHARC. A Core I7 would probably be faster than a TigerSHARC. However...
There are host of problems with using general purpose CPUs for something like an Axe-Fx. Some of these have been pointed out already. Power, heat, support, etc., etc.
One of the biggest issues though is lifespan. DSPs usually have a guaranteed lifespan, typically at least 10 years. CPUs are obsolete in two years. If you design the latest I7 into a product you won't be able to buy it in two years. So by the time you finish your product design the CPU is obsolete. They keep changing the sockets and the voltages and the bridge chips and everything else. It's a moving target. Not a big deal for computer makers, they're making millions of them with short design cycles. In the quantities that modeling products sell it's simply not sustainable.
Modern Intel CPUs are incredibly powerful and can easily replace a TigerSHARC. A Core I7 would probably be faster than a TigerSHARC. However...
There are host of problems with using general purpose CPUs for something like an Axe-Fx. Some of these have been pointed out already. Power, heat, support, etc., etc.
One of the biggest issues though is lifespan. DSPs usually have a guaranteed lifespan, typically at least 10 years. CPUs are obsolete in two years. If you design the latest I7 into a product you won't be able to buy it in two years. So by the time you finish your product design the CPU is obsolete. They keep changing the sockets and the voltages and the bridge chips and everything else. It's a moving target. Not a big deal for computer makers, they're making millions of them with short design cycles. In the quantities that modeling products sell it's simply not sustainable.
lol, a $1500 Line 6.
BUt the truth is that there is NO other hardware box in the market right now better then the Axe Fx, no matter what you say, that is the truth.