Reviews and questions about the entry-level MPC500
By bfrgus Sat May 19, 2018 11:06 am
Hi, first post on the forums!
I was wondering if the resampling function in the mpc500 is purely digital.
My question is: does the signal flow through the D-A converters before being resampled? Or is the function a Digital to Digital procedure? :hmmm:
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By Ill-Green Sat May 19, 2018 8:08 pm
The MPC is a digital sampler regardless, but from what I understood from the manual on Chapter 10 if I remember; "Recording The Main Out" as Akai called it. You are sampling as D/A to A/D. If you sampled an analog vinyl record into the MPC, that sound becomes digital and when you resample it, it goes from digital to analog and back to digital again.

At least thats how I gathered it. But whatever comes out those Main Outs will always be in analog form...just boxy :-D
By bfrgus Sun May 20, 2018 1:31 pm
Ill-Green wrote:The MPC is a digital sampler regardless, but from what I understood from the manual on Chapter 10 if I remember; "Recording The Main Out" as Akai called it. You are sampling as D/A to A/D. If you sampled an analog vinyl record into the MPC, that sound becomes digital and when you resample it, it goes from digital to analog and back to digital again.

At least thats how I gathered it. But whatever comes out those Main Outs will always be in analog form...just boxy :-D

Thanx for the reply! I am aware that mpc 500 is a digital sampler.
Well, tbh the manual's chapter is not really specific on this matter... for example, in the mpc 1000 whatever comes out of the "main outs" comes out of the "digital out" concurrently. This means it should not be impossible to bypass the D-A stage ( i think that this concept basically applies to any digital sampler ) .

The reason i am asking is that IF the resampling process is bypassing the D-A stage, resampling whole tracks and then transfering them to DAW via the CF card would be a killer option to get "rid" of the shitty converters of the 500...

Maybe someone with a little bit more knowledge could spot this by looking at the schematics?
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By tapedeck Sun May 20, 2018 3:39 pm
99% sure it'd be a strictly digital process. you'd have to run it in realtime or the converters would have to be over-specced by a factor of how much quicker the bounce takes vs recording in realtime.
By bfrgus Sun May 20, 2018 7:01 pm
tapedeck wrote:99% sure it'd be a strictly digital process. you'd have to run it in realtime or the converters would have to be over-specced by a factor of how much quicker the bounce takes vs recording in realtime.

I think this makes sense! If the recording is indeed real-time... I guess one can cross check by resampling the same loop 2-3 times and see if there is any delay on the recording. I currently don't have an MPC 500 so i can't check.
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By tapedeck Mon May 21, 2018 3:38 am
bfrgus wrote:
tapedeck wrote:99% sure it'd be a strictly digital process. you'd have to run it in realtime or the converters would have to be over-specced by a factor of how much quicker the bounce takes vs recording in realtime.

I think this makes sense! If the recording is indeed real-time... I guess one can cross check by resampling the same loop 2-3 times and see if there is any delay on the recording. I currently don't have an MPC 500 so i can't check.

almost...i don't mean there would necessarily be delay in the recording, i mean that time would have to pass while it generated / recorded the signal. even if that were fast, it would mean some signal being generated in time. the specs of the converters here would matter too as that would limit how fast you could bounce without frequency loss.
i highly doubt it would work that way
By bfrgus Mon May 21, 2018 2:06 pm
tapedeck wrote:almost...i don't mean there would necessarily be delay in the recording, i mean that time would have to pass while it generated / recorded the signal. even if that were fast, it would mean some signal being generated in time. the specs of the converters here would matter too as that would limit how fast you could bounce without frequency loss.
i highly doubt it would work that way

If that's the case, i'm one step closer to re-buying one.
Many thanks!
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By Harmoncj Mon May 21, 2018 5:16 pm
i'm assuming it is analog.

think about it, wouldn't it be much easier to just feedback the outputs to the inputs? otherwise youd have to sit and wait for it to render all the polyphony and effects
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By tapedeck Mon May 21, 2018 5:41 pm
Harmoncj wrote:i'm assuming it is analog.

think about it, wouldn't it be much easier to just feedback the outputs to the inputs? otherwise youd have to sit and wait for it to render all the polyphony and effects

no, actually the opposite.
if it's purely digital, then it can be computed in faster-than realtime. its not a ton of processor-heavy cpu going on here to just playback and effect audio - it's really fast to compute.
if it was analog, you'd literally have to wait in realtime for the signal to generate. if you wanted to go faster than realtime, the converters sample rates would have to be a factor higher than the highest sample rate to reproduce the audio correctly, and you'd still lose quality. for example, if the resampling happened at 2x the speed, the converters would have to be 88.2khz to give you 44.1k on the output. if resampling happened 10x faster than the actual playback time, youd have to have converters that went up to 44.1k x 10 = 441k....i've never seen converters go that high in a consumer audio product.
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By Lampdog Mon May 21, 2018 10:40 pm
It's digital.

Tapedeck is right.
By Emilie Wed Jun 06, 2018 5:46 pm
"I was wondering if the resampling function in the mpc500 is purely digital. "

It is pure digital, no DA/AD conversion in resampling

"My question is: does the signal flow through the D-A converters before being resampled? Or is the function a Digital to Digital procedure"

Pure sweet digital all the way :-)
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By motosega Wed Jun 27, 2018 5:15 pm
although it is digital, theres nothing to stop you doing it analog, the mpc500 can play sequences while it's recording.
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By Sharris Wed Jun 27, 2018 8:35 pm
motosega wrote:although it is digital, theres nothing to stop you doing it analog, the mpc500 can play sequences while it's recording.


If the MPC is digital, how would sampling while the sequencer plays make it analog?
Genuine question........
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By Wal Martian Wed Jun 27, 2018 9:53 pm
Sharris wrote:If the MPC is digital, how would sampling while the sequencer plays make it analog?
Genuine question........

Just remember analog is audio, digital is data (1's and 0's)
Record input = Analog to digital conversion
Master output = Digital to analog conversion.