Hybrid Bass/Guitar slide instrument

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StevenRowat1952
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Joined: Wed Nov 28, 2012 7:05 am

Hybrid Bass/Guitar slide instrument

Post by StevenRowat1952 »

Hi,
I'm very interested in your products, particularly the i2M. I have an unusual instrument, so I'd like to ask some questions:

The instrument was modified from an electric bass, and is now called an 'analude', with the main differences being:
a) It has high strings as well as low (notes as high as the high octave on a guitar, as low as the A string on a bass).
b) It is played as a slide.
c) It has stereo output, so the bass side and the high side can be output separately (but sometimes are output as mono).

Questions about the i2M applications for this instrument:
1. If I just output in mono, can the i2M recognize all the notes from lowest to highest? Or will it automatically choose one of its modes (bass or guitar) and then cut off either the high notes or the low notes? I ask because this is exactly what my Roland GI-20 does -- it has a switch for bass or guitar, and one way it cuts off some of the notes, and the other way it cuts them off at the other end.

2. I slide often more than an octave. Am I correct that the i2M can track up to +24 pitch bend?

3. Since I have stereo output, it would seem possible to put one i2M on each output, and assign one of them as bass and the other as guitar. Or...is the assignment automatic, made by the device itself? In which case I might be back to the problem of it cutting some of the notes off.

4. Again about using two of the i2Ms on the stereo output: I use a Mac; so I assume that I could gang them into an aggregate device, and record them together?

Thanks...

S.R.
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james
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Re: Hybrid Bass/Guitar slide instrument

Post by james »

That's an interesting instrument!

We have an endorsee who does something similar with a Chapman Stick with stereo outputs, and 2 i2Ms.
1. If I just output in mono, can the i2M recognize all the notes from lowest to highest? Or will it automatically choose one of its modes (bass or guitar) and then cut off either the high notes or the low notes? I ask because this is exactly what my Roland GI-20 does -- it has a switch for bass or guitar, and one way it cuts off some of the notes, and the other way it cuts them off at the other end.
The mode is not selected automatically, you have to do that. But in guitar mode, it will recognise down to the low E of a 4-string bass (E1). For finest precision of pitch-bend, the bass modes give better accuracy for the lowest notes, but won't reach the top notes you need.
2. I slide often more than an octave. Am I correct that the i2M can track up to +24 pitch bend?
Actually, the i2M will support up to +/- 36 semitones of pitch-bend. You just have to make sure the synth you use supports whatever you set this to.
3. Since I have stereo output, it would seem possible to put one i2M on each output, and assign one of them as bass and the other as guitar. Or...is the assignment automatic, made by the device itself? In which case I might be back to the problem of it cutting some of the notes off.
See above -- you assign the mode yourself, but in guitar mode it should be fine for your lowest notes anyway.
4. Again about using two of the i2Ms on the stereo output: I use a Mac; so I assume that I could gang them into an aggregate device, and record them together?
Yes, you can use several i2Ms together. If you only want to use the MIDI features, you don't need to create an aggregate device because it will simply appear as two new MIDI devices, so you can route these where you want them. If you want audio, you need to create an aggregate device (unless the software you use supports input from multiple devices).
StevenRowat1952
Posts: 3
Joined: Wed Nov 28, 2012 7:05 am

Re: Hybrid Bass/Guitar slide instrument

Post by StevenRowat1952 »

james wrote:...in guitar mode, it will recognise down to the low E of a 4-string bass (E1). For finest precision of pitch-bend, the bass modes give better accuracy for the lowest notes, but won't reach the top notes you need.
Thanks james. I've now read your spec page and the KVR threads about your products. I still have several questions:

1. Your specs state the latency as: "5 ms (E5), 17 ms (E2), 32ms (E1), 40 ms (B0)".
--For the E1 and B0, is this the latency in bass mode, or in guitar mode? And in either case, you say the bass mode would be better for those low notes, so what would the exact difference be (say for the E1 -- how many ms worse would it be in guitar mode, if this is the bass mode latency; or how many better if it's the reverse?)

2. Am I understanding correctly that the i2M passes both the audio signal and the midi converted signal through separately into the USB data? So that in, say, Logic on a Mac, I can record a PCM audio file on 1 track and the midi data on another track, simultaneously?

3. If so, just out of interest, what happens with the latency during recording? Are these lined up exactly by your software, or is there still a variable latency between the audio and the MIDI data, depending on the frequency of the note being converted?


Thanks

S.R.
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james
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Re: Hybrid Bass/Guitar slide instrument

Post by james »

1. Your specs state the latency as: "5 ms (E5), 17 ms (E2), 32ms (E1), 40 ms (B0)".
--For the E1 and B0, is this the latency in bass mode, or in guitar mode? And in either case, you say the bass mode would be better for those low notes, so what would the exact difference be (say for the E1 -- how many ms worse would it be in guitar mode, if this is the bass mode latency; or how many better if it's the reverse?)
The latency depends on the frequency of the note. The lower the note, the higher the latency. It is impossible for it to have lower latency than one period of the note.

The latency doesn't really depend on the mode that is set. But when playing fast, the pitch-tracking is faster in guitar mode compared to bass mode. What this means is that pitch-bend changes, or note changes that don't have an obvious "note-on" by plucking the string will be tracked faster in guitar mode.

The advantage of bass mode is that the pitch-bend tracking is a bit more accurate on the lower notes. Our converters track pitch-bend very precisely, so subtle pitch changes on the lowest notes will be more accurately tracked in bass mode. It call comes down to subtleties, and nuances of what you are trying to achieve.
2. Am I understanding correctly that the i2M passes both the audio signal and the midi converted signal through separately into the USB data? So that in, say, Logic on a Mac, I can record a PCM audio file on 1 track and the midi data on another track, simultaneously?
Yes, exactly. The i2M can also split MIDI into 6 different MIDI channels so you can record onto 6 MIDI channels. This lets you set up "splits" so that different notes can route to different MIDI tracks, or harmonies can be set up.
3. If so, just out of interest, what happens with the latency during recording? Are these lined up exactly by your software, or is there still a variable latency between the audio and the MIDI data, depending on the frequency of the note being converted?
The latency is variable. It also depends on the recording software, and what audio buffer sizes it uses. If it uses a large audio buffer size, the audio could actually lag the MIDI data that is recorded. But, usually, the MIDI data will lag slightly. Because the latency is variable, it's not possible to delay the audio in real-time to make it align.
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