That's actually what the switch is for, the only way to turn off the filter built into the DAC chip is to feed it 352 or 384. By turning my filter off you can then use an external program to implement your own filter if you want to play around with designing your own. In order to do that you have to turn off my filter and send your 352 or 384 to the DAC chip which will then turn off ITS filter. The switch lets you do that.
If you are not doing that just leave my filter on.
There HAS to be a filter, if you just send a 44.1 or 96 or whatever, the DAC chip will use its own. The only way to turn it off is to upsample to 352 or 384.
BTW a reconstruction filter is not evil, it is a very good thing, it's just that all the DAC chip implementations have made compromises that adversely affect the sound quality. That is what my filter is all about, doing it right so you get the good things from a proper reconstruction filter with out the bad side effects of the DAC chip implementations.
The subject is fairly deep and complicated, it takes WAY more time than I have right now to give it justice in this post. I have written extensively about it on other forums, if you want to track those down you can get some of the details.
The over all summary is that not having an oversampling reconstruction filter is NOT the best sound. It may be better than some of the horrible sounding filters used in DAC chips, but a properly done oversampling reconstruction filter sounds way better than either no filter or the ones built into the DAC chips. The secret is to find the RIGHT filter and how to implement it without degrading the sound. I have been working on this for many years and what is in the BH DAC is the culmination of all that research and listening.
John S.
