Performance of reading big binary arrays from IndexedDB is low in Javascript

I’m using IndexedDB for storing images and MP3 files as binary arrays but it doesn’t seem to be blazingly fast. Reading one MP3 file takes about 0.5-1 sec and it’s actually quite slow compared to streaming from server where delay is not noticeable. Any idea if it’s possible to stream data from IndexedDB or store file in two parts and then “stream” second part into already existing blob?