RE: Mini / Multi - Home Recording (FX)?

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MRNUTTY
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by MRNUTTY » Wed Jun 24, 2015 11:54 am

LOL! Autocorrect got me again :-)
VoyagerEB, Minitaur, LittlePhattyII, 4xSlimPhatty, Sub37, MF[2x101,2x102,103,104M,105,105B,105M,2x107,108M], 3xCP251, XV351, MP201;
2xMother 32, DFAM, Subharmonicon;
System 55 and Minimoog clones with lots of mods.

monsterjazzlicks
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by monsterjazzlicks » Wed Jun 24, 2015 1:15 pm

Hello John,
MRNUTTY wrote:If you want subjective full frequency response in a delay you need a high sample rate digital; 44.1KHz of greater. Analog pedals are slow, but distort nicely unless you get too much energy in the frequency range above the Norquist (Nyquist! Thanks the alien666!) limit, then analog, and/or digital is going to have artifacts. Digital artifacts are often less desirable. Judging from a lot of modern Electronic Music, the modern ear is less inclined to dislike it.
Thanks you very much for the reply and listening to the demo. I appreciate your expertise here.

Perhaps I have not explained my scenario accurately enough or misinterpreted your kind comments (probably BOTH knowing me! lol).

The artifacts are sounding even when I am NOT recording (ie just playing the MULTI, into to MXR CC, into the soundcard and straight out of the headphone socket [to my ears]). I think you may mean that it sounds OK when I am playing the recording IN, but once EXPORTED (or even played back) as a RECORDING, then this is when the issue arises. I had not even gotten as far as this latter stage. I dare say the same thing would happen even if I did not have CUBASE open, though was still using the soundcard on my PC.

In any event, when I did EXPORT/RECORD it was a 44.1kHz. So do you think it will solve the issue if I PLAY/RECORD the MULTI and MXR CC at (say) 48kHz (I think is the next one up)? I think this is what you are referring to?

Could you hear/detect the noise in the recording? I would imagine it will have stood out like a sore thumb because I heard it straight away, and your ears will be far more trained than mine for sure!

Best,

Paul

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MRNUTTY
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by MRNUTTY » Wed Jun 24, 2015 5:26 pm

Paul, I didn't give it super critical listen - so I can't answer your specific questions about that particular recording. However, here is some general info yuo might find useful; in any applications with sampling you're going to hear artifacts related to samples taken with different sampling rates, or samples taken at the same rate but not synchronized. This is why there are 'word clocks' in high end digital DSP, 'master clocks' to synch systems of sampling devices, and the long push from 44.1khz to 192khz, to increase the 'fidelity', and reduce 'sampling artifacts'. To a large extent analog delays don't have these specific problems because the fidelity is already to low due to heavy filtering in and out of the box, but in the case of very long delays - depending on how much storage your pedal has - your can hear 'sampling artifacts' in the output because you're clocking the Bucket Brigade Delayline lower than it's speced clock rate for analog delay applications.

Now I don't remember technically the range of artifacts are evident at that point. They may be charge value corruption (stored too long), or uneven setrup and hold times (the window to extract the correct charge window is inaccurate), or perhaps the clock is encoded with the data, and extracting the data without getting some of the clokc in there too is impossible. I forget... maybe someone else remember the details of BBD tech. But I do remember the sound of it.

So after alll that I gave it a listen with headphones, I don't hear anything abnormal about your delay pedal; just a rounded off high end. Can you make a recording that isolates what you hear? A stereo recording that hard pans the wet and dry signal would be fine too.
VoyagerEB, Minitaur, LittlePhattyII, 4xSlimPhatty, Sub37, MF[2x101,2x102,103,104M,105,105B,105M,2x107,108M], 3xCP251, XV351, MP201;
2xMother 32, DFAM, Subharmonicon;
System 55 and Minimoog clones with lots of mods.

monsterjazzlicks
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by monsterjazzlicks » Wed Jun 24, 2015 9:20 pm

Hi John,
MRNUTTY wrote:So after alll that I gave it a listen with headphones, I don't hear anything abnormal about your delay pedal; just a rounded off high end. Can you make a recording that isolates what you hear? A stereo recording that hard pans the wet and dry signal would be fine too.
Cheers for listening. I am pleased you were able to detect and put into words the high-end glitching.

Well one thing I found out for sure tonight is: using the HI OUTPUT on the MULTI circa DOUBLES the amount (level) of artifacts when the MXR CC is activated. I changed it round last night to try this different OUTPUT, and at the same time, hooked up the MXR. Bad idea because I should have eliminated each individually. But I just realized tonight that the OUTPUT was HI so I changed it back to LO, and the results were better.

I will make a dedicated recording for you tomorrow. I have been messing around on the gear this evening and so only just got your kind reply, thank you. The artifacts are ONLY in the UPPER (2') register. And they sound almost pitch-like (ie high harmonics).

I will have a good read of your advice on the SAMPLING side and try and get my head around it all!

Appreciate your time John.

Best,

Paul
Last edited by monsterjazzlicks on Wed Jun 24, 2015 9:54 pm, edited 1 time in total.

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Re: RE: Mini / Multi - Home Recording (FX)?

Post by monsterjazzlicks » Wed Jun 24, 2015 9:50 pm

Hello,

Here is a piece I made tonight after putting some time in thinking more about the MXR CARBON COPY DELAYsettings.

I set it to (what I would term) a SINGLE MEDUIM DELAY and tried (with little success) to play/keep in TIME with the damn thing! (I did not realize how tricky it was) :? But this was partly because I was trying to concentrate on shaping the FILTER and EG RELEASE (that's my excuse anyway!).

Because, as mentioned above, I came from the LO OUTPUT on the MULTI, the artifacts (as myself and MR_NUTTY were discussing earlier) are reduced.

I EXPORTED this (from CUBASE) as MP3 @ 44.1 and 48kHz (the latter being the highest option in mpeg). Though the FILE SIZE was IDENTICAL for both (2.21MB)?! And similarly I EXPORTED the WAV's @ 44.1 and 96kHz (39MB and 84MB respectively). But they are too big to upload to most places (though I could upload to MyDrive [Google] if anyone was interested in comparing)?

Anyway, here it is on You Tube and PicoSong:

https://www.youtube.com/watch?v=fi9Q8aXkpIo

http://picosong.com/g6x6

Many thanks,

Paul

monsterjazzlicks
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by monsterjazzlicks » Thu Jun 25, 2015 7:03 pm

"Funky Slap Back" - dedicated to Mark Warren, London, UK (Seaman - 2015).

Rockin' out on the MULTIMOOG with MXR DELAY set to produce a SLAP BACK FX.

The SPEED is so fast that it sounds almost like double-tracking/chorus!

Performed in 1 x pass with exception to the INTRO and ENDING (which use a slightly different PATCH), and the PORTAMENTO FX (midway point OVERDUB) which uses a very LONG DELAY (time).

'Twas a bugger to try and play! :shock:

Please find on You Tube or PicoSong:

https://www.youtube.com/watch?v=qmZ99fW ... e=youtu.be)

http://picosong.com/gQ6g

Cheers,

Paul

monsterjazzlicks
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by monsterjazzlicks » Thu Jun 25, 2015 8:17 pm

Mr Nutty,

Here is an example of the artifacts on the MultiMoog with the MXR CC DELAY pedal.

I play a few notes in three different registers without the MXR, and then the same pattern again (more or less) with the MXR turned ON. The HIGHER I play, the MORE the artifacts become present.

I watched a couple of You Tube videos (of guitarists) and they both raved about how pure and clean the MXR delay FEEDBACK's were (ie the reproduction tone was unaffected).

I uploaded the demo to PicoSound:

http://picosong.com/gQhs

Much appreciated,

Paul
Last edited by monsterjazzlicks on Thu Jun 25, 2015 8:34 pm, edited 1 time in total.

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MRNUTTY
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by MRNUTTY » Thu Jun 25, 2015 8:28 pm

Paul, yes I can clearly hear it on this last recording. I couldn't find any spec for sample rate on this pedal, so I couldn't say much more than it sounds like some significant energy in the high notes is being mangled by the Nyquist limit - but I can't pull any numbers out of my hat without knowing the sample rate.
VoyagerEB, Minitaur, LittlePhattyII, 4xSlimPhatty, Sub37, MF[2x101,2x102,103,104M,105,105B,105M,2x107,108M], 3xCP251, XV351, MP201;
2xMother 32, DFAM, Subharmonicon;
System 55 and Minimoog clones with lots of mods.

monsterjazzlicks
Posts: 294
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by monsterjazzlicks » Thu Jun 25, 2015 8:36 pm

Hi,
MRNUTTY wrote:Paul, yes I can clearly hear it on this last recording. I couldn't find any spec for sample rate on this pedal, so I couldn't say much more than it sounds like some significant energy in the high notes is being mangled by the Nyquist limit - but I can't pull any numbers out of my hat without knowing the sample rate.
Thanks for listening. I knew you would here them instantly.

If I can find the box, maybe it has a MANUAL in it. Do you think the SAMPLE RATE will be mentioned in there?

Cheers,

Paul

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MRNUTTY
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by MRNUTTY » Fri Jun 26, 2015 8:37 am

Oddly, I haven't seen it spec'd anywhere for analog delays, possibly because they're variable sample rate designs. A fixed sample rate device, like nearly all modern gear spec'd at 44.1Khz, 48, 96, 192, etc... is (nearly) always spec'd. Perhaps it's too much to expect from a pedal. In any event, if you have the minimum and maximum delay time and the amount of storage (number and size of delay BBD chips), you can calculate the sample rates, and compare them to then frequency and harmonic content of the notes you're playing. It's a lot of work to get the answer you already know though from the apparent cutoff frequency of the filters in the pedal though; multiplied by two or three.
VoyagerEB, Minitaur, LittlePhattyII, 4xSlimPhatty, Sub37, MF[2x101,2x102,103,104M,105,105B,105M,2x107,108M], 3xCP251, XV351, MP201;
2xMother 32, DFAM, Subharmonicon;
System 55 and Minimoog clones with lots of mods.

monsterjazzlicks
Posts: 294
Joined: Mon Aug 12, 2013 8:34 pm

Re: RE: Mini / Multi - Home Recording (FX)?

Post by monsterjazzlicks » Fri Jun 26, 2015 9:51 am

Hi MN,
MRNUTTY wrote:Oddly, I haven't seen it spec'd anywhere for analog delays, possibly because they're variable sample rate designs. A fixed sample rate device, like nearly all modern gear spec'd at 44.1Khz, 48, 96, 192, etc... is (nearly) always spec'd. Perhaps it's too much to expect from a pedal. In any event, if you have the minimum and maximum delay time and the amount of storage (number and size of delay BBD chips), you can calculate the sample rates, and compare them to then frequency and harmonic content of the notes you're playing. It's a lot of work to get the answer you already know though from the apparent cutoff frequency of the filters in the pedal though; multiplied by two or three.
Well I found the BOX but there is no MANUAL. I keep, and look after, all of my musical properties but it would seem strange that it came with no documentation at all?! Though maybe it did (I bought it a couple of years ago).

lol, gee that's a lot of MATHS to work out every note (too above me for sure)! I am still getting head around you earlier reply regarding NYQUIM etc!

What does: 'BBD' mean please?

I watched some more demonstration You Tube videos on it this morning and it appears (unbeknown to me!) that if you open up the device, there are (what people call) 'trimming pots' with which you can modify how the TOP END FREQ's react (or words to that effect). Though hardly anyone discusses this and it is only mentioned in passing. Nobody has demonstrated this and in all instances owners have RETAINED all settings as per FACTORY default.

Thanks a lot,

Paul

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DonutDude
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by DonutDude » Fri Jun 26, 2015 12:05 pm

Paul,
You can find a .pdf of the manual here: http://www.jimdunlop.com/product/m169-c ... alog-delay

monsterjazzlicks
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by monsterjazzlicks » Fri Jun 26, 2015 12:59 pm

Thanks a lot,
DonutDude wrote:You can find a .pdf of the manual here: http://www.jimdunlop.com/product/m169-c ... alog-delay
I will take a look. Hopefully you can download it as PDF.

Ta,

Paul

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MRNUTTY
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Re: RE: Mini / Multi - Home Recording (FX)?

Post by MRNUTTY » Fri Jun 26, 2015 2:03 pm

monsterjazzlicks wrote:lol, gee that's a lot of MATHS to work out every note (too above me for sure)! I am still getting head around you earlier reply regarding NYQUIM etc!

What does: 'BBD' mean please?
Hi Paul,

BBD is Bucket Brigade Delay - an analog delay line. Here's a blog specifically about your pedal http://guitarwtf.com/2012/05/01/wtf-is- ... echnology/

The way it works is there is a chain of capacitors that hold a continuous value - charge; which is proportional to the instantaneous input signal. The BBD is controlled by a clock, which governs the transfer of the charges from one bucket to the next. On each clock, the input of the pedal is sampled and placed in the first bucket, also each bucket will transfer the charge from the previous one to itself, the final bucket will output the charge to the output stage of the pedal. There is a master clock that provides a signal to each bucket, the input and output stage. This clock is referred to as the 'rate', the rate determines the 'delay' depending on the amount of storage you have. The rate is variable. The lower the rate, the slower charges proceed through the bucket brigade. What's especially nice and musical about this is that overdriving the charges produces and 'analog distortion', and making swift adjustments to the clock rate doesn't distort the relationship between successive charges or samples.

This is different from a fixed rate delay. In a fixed rate delay; the input, output are always clocked at the same rate. There is no bucket bridge per se. Instead samples are stored in fixed location in a randomly addressable storage device (DRAM or SRAM). The address for storing input samples is a continuous range of values 1, 2, 3, 4... and so on, the output addressing however depends on the delay time. While the delay time is constant the output addressing is also continuous 1+dt, 2+dt, 3+dt, 4+dt... and so on, where 'dt' is an offset added to the address to implement the delay - the idea here is that the offset provided for a delay time between when the input stores the sample and the output retrieves it. The ugly part happens when the delay time is changing. When that is happening the value of 'dt' is being modulated, allowing some samples to be either missed or retrieved twice. This creates an anharmonic relationship between the sample rate and the value of sample that are being retrieved, because the values are no longer harmonically related as they were when they were stored. Note all: I really simplified the operation of the fixed sample rate storage store and retrieval algorithm, so don't go poking holes in it - I know they're there. I know how they work, I'm just not wordy guy and I'm late for my nap :-)
I watched some more demonstration You Tube videos on it this morning and it appears (unbeknown to me!) that if you open up the device, there are (what people call) 'trimming pots' with which you can modify how the TOP END FREQ's react (or words to that effect). Though hardly anyone discusses this and it is only mentioned in passing. Nobody has demonstrated this and in all instances owners have RETAINED all settings as per FACTORY default.

Thanks a lot,

Paul
The danger of changing those pots is that they are set using calibration methods that may not be evident in the sound of the output. They can be sampling windows, where for most setting they're OK, but worse case conditions will show up poor setting, and you don't know what that condition is. They will certainly contribute to the amount of artifact you hear on the output. So advice is to leave them alone, unless you have the calibration procedure, know what they do, and have the equipment needed to make the setting. I was a hardware guy IRL, we do things that are not always evident unless you know the whole story :-)


-John
VoyagerEB, Minitaur, LittlePhattyII, 4xSlimPhatty, Sub37, MF[2x101,2x102,103,104M,105,105B,105M,2x107,108M], 3xCP251, XV351, MP201;
2xMother 32, DFAM, Subharmonicon;
System 55 and Minimoog clones with lots of mods.

monsterjazzlicks
Posts: 294
Joined: Mon Aug 12, 2013 8:34 pm

Re: RE: Mini / Multi - Home Recording (FX)?

Post by monsterjazzlicks » Fri Jun 26, 2015 2:47 pm

Hi John,
MRNUTTY wrote:BBD is Bucket Brigade Delay - an analog delay line. Here's a blog specifically about your pedal http://guitarwtf.com/2012/05/01/wtf-is- ... echnology/
That was very interesting to read! I never knew anything about that before. Cheers.
MRNUTTY wrote:The way it works is there is a chain of capacitors that hold a continuous value - charge; which is proportional to the instantaneous input signal. The BBD is controlled by a clock, which governs the transfer of the charges from one bucket to the next. On each clock, the input of the pedal is sampled and placed in the first bucket, also each bucket will transfer the charge from the previous one to itself, the final bucket will output the charge to the output stage of the pedal. There is a master clock that provides a signal to each bucket, the input and output stage. This clock is referred to as the 'rate', the rate determines the 'delay' depending on the amount of storage you have. The rate is variable. The lower the rate, the slower charges proceed through the bucket brigade. What's especially nice and musical about this is that overdriving the charges produces and 'analog distortion', and making swift adjustments to the clock rate doesn't distort the relationship between successive charges or samples.

This is different from a fixed rate delay. In a fixed rate delay; the input, output are always clocked at the same rate. There is no bucket bridge per se. Instead samples are stored in fixed location in a randomly addressable storage device (DRAM or SRAM). The address for storing input samples is a continuous range of values 1, 2, 3, 4... and so on, the output addressing however depends on the delay time. While the delay time is constant the output addressing is also continuous 1+dt, 2+dt, 3+dt, 4+dt... and so on, where 'dt' is an offset added to the address to implement the delay - the idea here is that the offset provided for a delay time between when the input stores the sample and the output retrieves it. The ugly part happens when the delay time is changing. When that is happening the value of 'dt' is being modulated, allowing some samples to be either missed or retrieved twice. This creates an anharmonic relationship between the sample rate and the value of sample that are being retrieved, because the values are no longer harmonically related as they were when they were stored.
Wow, I did not expect a full explanation like that! Thanks very much.

I never heard of 'anharmonic' though before? Just enharmonic and disharmomic.
MRNUTTY wrote:The danger of changing those pots is that they are set using calibration methods that may not be evident in the sound of the output. They can be sampling windows, where for most setting they're OK, but worse case conditions will show up poor setting, and you don't know what that condition is. They will certainly contribute to the amount of artifact you hear on the output. So advice is to leave them alone, unless you have the calibration procedure, know what they do, and have the equipment needed to make the setting. I was a hardware guy IRL, we do things that are not always evident unless you know the whole story
Quite possible why nobody in the You Tube demo's has ever re-configured it then! Plus, everyone seems to be happy with the FACTORY default setting.

What is IRL please? You mean that you were working in IRELAND?

Many thanks,

Paul

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