Most of the YouTube to MP3 converters that are free or web-based struggle with bigger files. The processing of a file such as the sample above takes time—depending on how it is done, and large files will be much easier to work with. A 2h YT video at best yields a ~200MB MP3 of only moderate quality (i.e., not exactly WAV.) A lot of converters cap you at like 100 MB or they only let your video be up to 90 minutes long (which would eliminate a podcast, lecture, or an entire album) so what makes UnitPDF any different.
If you have larger files to convert than Handbrake can handle, better software-based options include Any Video Converter Ultimate or 4K YouTube to MP3. Thanks to optimized encoding algorithms and the ability to produce high-bitrate outputs without sacrificing any speed. E.g., a 4K Video Downloader can do the job in under ten-minute FOR A THREE-HOUR VIDEO with almost > no< quality loss. In this context, efficiency is typically related to multi-threading capabilities in the software(having multiple parts of a task executed on several processing cores). And that is essential especially for large files, as it also decreases the likelihood of occurring errors or crashes in inferior converters.
We have industry benchmarks displaying hardware acceleration can even ensure up to a 40% fillip in conversion speeds; particularly when it comes to rendering 4K UHD and HD content. Although this feature is pretty standard in top converters that benefit from GPU acceleration as well. And the extra processing power helps maintain audio quality in long files, which is easy to lose track of—think lags and skips or even that one glitch you hear under compression.
Most online converters are restricted by server bandwidth and processing power, though. In 2022, it was reported that as many as 60% of users converting video longer than two hours with free conversion services experience out-of-use errors or quality problems. These tools also proved impractical for scale due to a process that average conversion speeds of 500 KB/s.
Free services also restrict you by cloud storage limits of files sizes. For example, some platforms have an upper limit of 50 MB for downloads which is simply inappropriate for large MP3s coming from long videos. On the other hand, standalone software presents a greater amount of limitations but allows for virtually unlimited output sizes which can be ideal if you are looking to have high-quality audio.
Whether YouTube to MP3 converter can download big files well, that is not your call as it lies mostly in the hands of said converter. Free and online tools generally can not handle more than a moderate file size (500MB or so) at once, while premium solutions also dedicated software have no problems running even the highest bitrate files as quickly as possible without any degradation in quality. Aiming for a consistent performance, it is still preferable to use the one that can convert youtube videos very long with reliability will always go to those dedicated mp3 downloaders.