Just recently I have been trying to record a sample from my computer through the input on the keyboard. Everything was going great. I got the sample, saved it to FLASH, auditioned it and it sound nice and loud. But when I bring it in to VOICE mode, the sample is substantially quieter than when I auditioned it. I have gone back and forth but each time it is loud when auditioned and soft when played through VOICE mode.

This is normal and can be adjusted for. When you are recording (sampling) you are listening to the audio of the source. Both the RECORD MONITOR and the initial Audition function are set so the audio is heard as it came in. Once you begin the process of building it into a Motif XF structure you will notice a significant decrease in its amplitude (this is normal). You can adjust for this fairly easily.

Not to just give you a fish... here are instructions on how to catch your own fishes! 🙂 (bare with it... once you begin creating your own audio samples, the following knowledge will only help you understand what is going on).

When you initially created a sample (depending on how you record it) you can reduce its amplitude impact or increase its amplitude impact or you can keep it exactly the same amplitude. From what you wrote it seems like you are routing the signal from the computer through an analog output and going into the Motif XF via the A/D INPUT (analog to digital input (This is one way to do it). If you have the FW16E (FireWire option) you could route the audio digitally from the computer into the Motif XF sampler via FW. This avoids the D-to-A and A-to-D conversion process you are going through. When you sample using this D/A and A/D conversion method or when you sample by digital transfer, you can greatly enhance the audio sample using the parameters of the Motif XF's Sample and VOICE architecture.

Turning raw audio into Music
In order for the audio to work musically inside a Motif XF VOICE - it is initially reduced in amplitude (this is normal). Your sample is not going to be the *only* one playing back... in fact, immediately your sample goes from being a single piece of audio to being able to be played 128 times simultaneously (it becomes potentially 128 note POLYPHONIC). Imagine if the VOLUME stayed the same for all 128 instances, maximized in each instance, and you played all 128 instances of this audio simultaneously... And while sound output levels to do not increase arithmetically, (the increase is logarithmic) but even so still this would cause problems - without getting too, too technical, the volume of the single instance is initially reduced. This is normal. Do not panic - you can fix it as you require.

BACKGROUND on What is happening
The difference between a raw sample (.Wav) and a Motif XF Waveform is the additional parameters that the Motif XF assigns to it. These include (most importantly) a KEY on which the original pitch of the sample is assigned and reproduced. By default, this is usually "middle C" (C3). Why? So that you can easily pitch it across the keyboard (if you so desire) allowing it to sound both higher and lower than the original pitch of the recording _ this is obviously useful in creating musical instruments that tune yo scales left to right across the keys. Also the raw sample is assigned a VELOCITY RANGE - by default, 1-127. This is the full range of velocities for MIDI protocol. This means that no matter how hard (actually how fast) or how soft (how slowly) a key is pressed it will trigger output (initially at a fixed level).

If you would rather a sample respond to this VELOCITY RANGE with some kind of musical sensitivity (touch sensitivity/velocity sensitivity - this is setup among the many VOICE parameters. (we'll discuss that later).

These basic Waveform parameters (KEY RANGE and VELOCITY RANGE) are applied immediately when the audio sample is placed in a Motif XF Waveform.
Press [INTEGRATED SAMPLING]
You arrive at the Sample Select screen.
Your sample will be found in one of these Waveforms numbered 001-128.
A Waveform organizes samples into useable groups.

Recall your Waveform by its number.
In the middle of the screen is a large box with KEY RANGE and VELOCITY RANGE of the sample. There is room for some 256 samples in each WAVEFORM (they are numbered in the first column). If you recorded just one, it will appear at the top of the list.

Other basic default settings include things like PLAY direction/mode: That is, whether the audio is played once (called "one shot") or repeats ("loop"), whether it plays normally or plays in "reverse"... and there are a few others.

Press the AUDITION button hear the response
Press a KEY in the KEY RANGE (initially it is assigned a single key KEY RANGE C3-C3) and notice that it plays a fixed Volume... no mater how hard or soft you strike the key.

Building a VOICE: From WAVEFORM to ELEMENT
Next... a WAVEFORM is one of eight building blocks that can make up a normal Motif XF Voice. The Waveform is placed in an entity called the ELEMENT. Eight Elements can be used to make up a normal VOICE. The ELEMENT is a set of additional parameters that help to further refine the Waveform... you can now do things like NOTE SHIFT it to a different region of the keyboard. But only if you extended the KEY RANGE of the WAVEFORM. What this means is, if you leave the KEY RANGE set to C3-C3, then only when you strike C3 will you be able to hear the sound. If you extend the KEY RANGE of the WAVEFORM to C3-C4 then the thirteen keys from C3 through C4 will sound the sample... tuning defaults to "Equal Temperament" scaling. The full range can be set to 10 and a half octaves (C-2 through G8)

OTHER ELEMENT parameters: You can apply things like Pitch Envelopes, Filter Envelopes, Amplitude Envelopes that shape how the audio behaves over time ... does it change pitch as it sounds, does it get brighter or darker, does it get louder then softer over time. You can TUNE it, you can further adjust the SENSITIVITY to Pitch change, to Timbre change, to Loudness change, so that the harder or softer you strike a key can cause dramatic changes in how the audio plays back. This makes your audio more "musical". Many different audio devices are able to playback a .wav as it is, but they cannot immediately map it across keys for musical pitching... that is what these parameters are doing - turning your audio into a musical 'instrument' sound that can be performed, if necessary, from you chromatic keyboard.

You can EQ the audio - changing its high and low frequency content, you can BOOST the volume by as much as +18dB (That is a tremendous amount of change). Each Element has its own complete set of controls!

A raw sample (as a .wav) can only playback exactly as recorded... by the time you apply the Motif's Waveform parameters and the Element parameters you can change dramatically how that raw sample sounds in response to striking a key, moving a wheel, moving a foot pedal, stepping on a sustain or sostenuto pedal, touching the Ribbon controller, etc., etc.

VOICES access Waveforms via the Element
Go to the VOICE into which you placed the sample.
Press [EDIT]
You can now view the two sets of VOICE parameters: "COMMON" parameters (those that affect all things in the VOICE) and individual "ELEMENT" parameters.
COMMON can be seen by pressing and lighting the dedicated [COMMON EDIT] button
ELEMENT can be seen by pressing and lighting a numbered button [1]-[8] depending on how many Elements you have in the VOICE. Buttons 9-16 light when a corresponding Element 1-8 directly above it, is activated.

Press [1] to select Element EDIT _ see the parameters for your Waveform (most likely assigned to Element 1)

Notice that the F (Function) and SF (SubFunction) buttons will allow you to access all the Element parameters.
[F1] OSCILLATOR - is where the Waveform is assigned to Element 1
[F2] PITCH is where you can adjust things concerning its pitch
[F3] FILTER is where you can adjust things concerning its timbre
*[F4] AMPLITUDE is where you can adjust thing concerning its loudness*
[F5] ELEMENT LFO is where you can apply modulation (vibrato, wah-wah, and tremolo)
*[F6] EQ is where you can adjust the loudness by frequency or boost the entire frequency range*

We've placed an asterisk (*) next to AMPLITUDE and EQ - because here is where you can quickly adjust the loudness response of your audio.

For the purpose of your question, focus in on these:
[F4] AMPLITUDE - here you can study how the Element is set to respond to your key-on velocity... velocity sensitivity
Press [F4] AMPLITUDE
Press [SF1] LEVEL/PAN
By default, your Waveform is set to a volume of 127 but the VELOCITY SENSITIVITY defaults to +0 (no change per key-on velocity).
A Velocity Sensitivity setting of +32 will result in a response where for each increment increase in EFFORT will be matched with an equal increment increase in OUTPUT LEVEL.
A Velocity Sensitivity setting of +63 will result in a response where low velocities will cause no sound at all, and only maximum EFFORT will cause any OUTPUT LEVEL at all.
Negative settings reverse the EFFORT/OUTPUT LEVEL function.
The CURVE also influences this Effort-In/Level-Out relationship... A +32 Level Sensitivity with a Curve of 2 is a perfectly linear response to key-on velocity.

Finally, look at [F6] EQ - an Equalizer is a device that can boost or cut output level according to the frequency (pitch) of the signal. Each Element has access to a 2-Band EQ or a 1-Band Parametric EQ - these are used to fix specific issues within an audio sample set. The EQ can also be used as a straight BOOST device (all frequencies are BOOSTED equally)... you have the following settings: +6dB, +12dB, +18dB

These setting allow you to restore any loss in Volume that occurred when you placed your audio into a Motif XF entity. Because in music 128 notes never (or should) never be played all at once... think about it: musically that is quite an unusual situation. Music is a set of instruments coming and going, playing together and alone, not all instruments are typically sounding together. And ensembles that can produce 128 musical tones at once are quite rare indeed. So use the BOOST wisely... +18dB is absurd... if you find you need to boost your Element more than +6 (or +12dB at max) we highly recommend you re-record your audio sample... with better Gain Staging (in other words, that is for very weak signals only).

Hope that is helpful - we are not at all sure whether you were creating a musical instrument sound or just an audio sound clip (sound effect, or event)... but the above should help you with navigating placing a Sample into a Motif XF Voice.

Let us know. Please see the complete tutorial on Sampling in the MOTIF XF section under "Resource" here on YamahaSynth. If you get stuck or have questions, post back here.