Changing sample rate in Sound Forge Pro 2026 is a conversion job, not a metadata edit. For normal work, open Process → Resample → Resample, enter the target rate, leave Set the sample rate only off, choose a phase setting, and click OK. That preserves the file’s pitch and duration while Sound Forge calculates a new set of samples.
The warning matters because Sound Forge can also change only the rate stored for playback. That makes the same samples play faster or slower and shifts pitch with them. It is useful for a wrongly tagged recording; it is the wrong tool for delivering a 48 kHz file from a 44.1 kHz master.
This guide uses the current Sound Forge Pro 2026 Resampling help, last modified March 4, 2026. The current dialog uses Phase Setting and Allow aliasing/imaging above 3 dB. Older tutorials that show an Interpolation Accuracy slider or a separate iZotope 64-bit SRC command describe legacy releases, not the 2026 workflow.
Change sample rate without changing pitch
- Open the audio file and note its current sample rate in the status bar.
- Choose Process → Resample → Resample.
- Enter the required value in New sample rate, such as 44100, 48000 or 96000 Hz.
- Choose Intermediate for the safest general-purpose phase setting.
- For normal downsampling, leave Allow aliasing/imaging above 3 dB unchecked so the anti-aliasing protection remains active.
- Confirm that Set the sample rate only is unchecked.
- Click OK, then save the converted result under a new name if you need to keep the source unchanged.
If the target comes from a broadcaster, video editor, game engine, sampler or client, use that specification. Don’t convert to 96 kHz just because the number is larger. Sound Forge’s current glossary describes 44.1 kHz as common for CD audio and 48 kHz as the common video rate; neither is a universal delivery rule.
What the Sound Forge 2026 controls actually do
New sample rate
This is the rate of the converted file in samples per second. A 48,000 Hz file stores 48,000 sample values per channel for each second of audio. Converting to a lower rate reduces the available frequency range and usually reduces file size. Converting upward interpolates additional samples and increases file size, but it does not reconstruct information that the original recording never captured.
The highest frequency that can be represented is half the sample rate, the Nyquist frequency. A 44.1 kHz file therefore has a theoretical limit of 22.05 kHz; a 48 kHz file has a 24 kHz limit. The practical reason to know this is downsampling: content above the new limit has to be filtered before the new samples are calculated.
Phase Setting: Minimal, Intermediate or Linear
The current dialog no longer asks for an interpolation-accuracy number. It offers three phase behaviours:
- Intermediate is the official recommendation for most uses. It balances transient behaviour and phase response.
- Linear preserves phase relationships more consistently across frequencies, but can place ringing both before and after sharp transients.
- Minimal keeps pre-ringing away from transients, while phase varies more at lower frequencies.
Intermediate is the sensible starting point unless a delivery test or a specific transient problem gives you a reason to compare the other two. “Linear” is not automatically better; it is a different trade-off.
Allow aliasing/imaging above 3 dB
This label is easy to misread. For an ordinary sample-rate conversion, especially when reducing the rate, leave it unchecked. Sound Forge then applies the filtering needed to keep frequencies above the new Nyquist limit from folding back into the audible band as false tones.
The 2026 help says you may enable the option when you are certain the signal contains nothing above half the target sample rate. That can make processing faster and reduce ringing, but it is an exception for known material, not a default “quality” switch.
When “Set the sample rate only” is correct
Set the sample rate only changes playback interpretation without calculating new samples. If a 44.1 kHz file is relabelled as 48 kHz, it plays about 8.84% faster and roughly 1.47 semitones higher. Relabelling 48 kHz as 44.1 kHz does the reverse.
That behaviour is useful when the audio data is correct but the stored rate is wrong—for example, a raw transfer imported with the wrong header value. It can also be used deliberately for tape-style speed and pitch changes. It should not be used to meet a normal delivery specification.
If a conversion unexpectedly changes pitch or duration, undo it and reopen Resample. The first thing to check is this box. Changing the rate through a properties field or status-bar control without resampling can create the same symptom.
Choose the target rate from the destination
| Destination | Practical choice | What to verify |
|---|---|---|
| Audio CD | 44.1 kHz | The authoring workflow also expects the correct bit depth and channel format. |
| Video or broadcast handoff | Commonly 48 kHz | Use the editor’s or broadcaster’s written specification. |
| Music distribution | Keep the native master unless the distributor requests another rate | Do not infer a platform requirement from a generic web chart. |
| Sampler, game or hardware device | Exactly what the device accepts | Check supported rates, channels and sample format together. |
| Archive or further processing | Usually keep the source rate | A larger rate does not restore missing bandwidth. |
Avoid repeated conversions. If the source is 96 kHz and the final deliverable is 48 kHz, work from the 96 kHz source and make one conversion at the end. Converting 96 → 44.1 → 48 kHz adds another filtering and interpolation pass without adding useful information.
Upsampling and downsampling: the useful distinction
Upsampling creates intermediate sample values so the file can run at a higher rate. It can be useful when a specific processor behaves better at that rate, but many modern plug-ins oversample internally when needed. Upsampling a finished 44.1 kHz file to 96 kHz does not extend its original recorded bandwidth or make it a true high-resolution source.
Downsampling reduces the number of samples and the reproducible bandwidth. A proper converter filters frequencies that cannot exist at the new rate before decimation. That is why Sound Forge’s aliasing option deserves more attention than any “higher numbers sound better” argument. The underlying interpolation and filtering problem is also described in Julius O. Smith’s Digital Audio Resampling material at Stanford CCRMA.
Sample rate is separate from bit depth. Resampling changes the time grid; bit-depth conversion changes how each sample value is represented. If the destination also requires a lower bit depth, perform that conversion once at final delivery and use dither where appropriate. The Sound Forge conversion guide covers format and bit-depth decisions.
Export and batch workflows
For one file, the safest audit trail is simple: keep the source, run Resample, then use Save As with a new filename that includes the target rate, such as mix-v7-48k.wav. Reopen the result and confirm its status-bar rate before delivery.
When many files need the same destination format, use the Batch Converter workflow instead of repeating manual clicks. Build one preset, test it on a copy of a single file, verify rate, duration, channels and output format, then run the full folder. That test catches the expensive mistakes: changing only the header, choosing the wrong destination folder or applying a rate intended for a different device.
Troubleshooting sample-rate changes
The result is faster and higher, or slower and lower
The rate was probably changed without resampling. Undo if possible, then use Process → Resample with Set the sample rate only disabled.
The converted file has high-frequency whistles or roughness
Check whether Allow aliasing/imaging above 3 dB was enabled during downsampling. Repeat the conversion from the untouched source with it disabled.
The audio interface changes rate or will not play the file
This is often a device-clock or driver issue, not a file-conversion failure. Confirm that Windows, the ASIO driver and the open Sound Forge file agree on a supported rate. The recording setup guide covers interface and ASIO configuration.
I cannot find Interpolation Accuracy or 64-bit SRC
You are probably comparing Sound Forge 2026 with an older manual or screenshot. The current Boris FX Resample page documents New sample rate, Phase Setting, Allow aliasing/imaging above 3 dB and Set the sample rate only. It does not document an iZotope 64-bit SRC submenu.
Frequently Asked Questions
How do I change sample rate in Sound Forge Pro without changing pitch?
Choose Process → Resample → Resample, enter the target rate and keep Set the sample rate only unchecked. Sound Forge then converts the sample data while preserving pitch and duration.
Which Phase Setting should I use?
Use Intermediate for most conversions. The 2026 help recommends it as the general-purpose balance. Linear preserves phase more consistently but can add pre/post-ringing; Minimal protects transient onset from pre-ringing while allowing more low-frequency phase variation.
Should I enable Allow aliasing/imaging above 3 dB?
Normally no, especially when downsampling. Leave it unchecked so anti-alias filtering remains active. Enable it only when you know the source has no content above half the target rate and accept the trade-off described in the current help.
Why did changing sample rate change speed and pitch?
The file rate was relabelled without resampling. Use Process → Resample with Set the sample rate only disabled. Reserve the rate-only option for correcting a wrong header or for a deliberate speed-and-pitch effect.
Does converting 44.1 kHz to 96 kHz improve quality?
No. It creates additional interpolated samples but cannot recover frequencies or detail absent from the source. Upsample only when a tested processing or delivery workflow requires it.
Is 44.1 kHz or 48 kHz better?
Neither is universally better. 44.1 kHz is the established audio-CD rate; 48 kHz is common in video. Follow the destination specification and avoid unnecessary conversions.
Can I change a folder of files at once?
Yes. Use Sound Forge’s Batch Converter, test the preset on one copied file, verify the output, and then process the folder. Keep the originals until the batch has passed QA.
When the destination also specifies codec, bit depth or channel layout, continue with the Sound Forge file-conversion workflow. For a folder of deliverables, build and test one preset with the Batch Converter guide before processing the full set.
Last fact-checked: August 2, 2026 against the current Boris FX Sound Forge 2026 Resample documentation.