[infinitesymphony]

I hadn't heard of HT bypass until it came up in the DAC1 thread, and now I want to learn more. I've read a bunch of explanations about it, but I'm still confused about what it is or why anyone would want to use it...

What's the purpose of HT bypass? If someone could draw a diagram and/or explain, I'll be very grateful.

 

[HeadphoneAddict]

Let's say you wanted to have your 2-channel system in the same room with your home theater. You could use the DAC1 for the 2 channel pre-amp, and have it feed a headphone amp a 2-channel speaker amp.

But what if you wanted the 5.1 channel theater system to also use/share the same front 2 speakers and that the 2 channel system controls? Well, you put the DAC1 in-between the home theater audio video receiver's preamp and the front 2 channel amp - feeding the home theater pre-amp's signal into the DAC1 analog input.

Since this means you are going from a "pre-amp > pre-amp (DAC1) > "power amp" there is one too many preamps. You can use the HT setting to allow the DAC1 to do nothing with the signal other than to pass it right through to the amp, with no changes or signal control. Now, the home theater has total control over the front 2 channel, along with the center, surround and subwoofer.

When you are done with the movie, and want to go back to listening to your 2 channel speakers or headphones, you turn off HT mode, and select a different input on the DAC1.

 

[infinitesymphony]

Ah, okay, I think I understand. I wasn't getting how HT bypass was different from a tape loop / aux. output, or just sending the signal from the A/V receiver's preamp outputs directly to the two-channel power amp.

It still seems like unnecessarily complicating the signal path (a lot of extra connections and cabling means more resistance, capacitance, etc.), but from an ergonomics standpoint, I get it.

Thanks for the explanation.

 

[HeadphoneAddict]

Quote:

Originally Posted by infinitesymphony /img/forum/go_quote.gif Ah, okay, I think I understand. I wasn't getting how HT bypass was different from a tape loop / aux. output, or just sending the signal from the A/V receiver's preamp outputs directly to the two-channel power amp. It still seems like unnecessarily complicating the signal path (a lot of extra connections and cabling means more resistance, capacitance, etc.), but from an ergonomics standpoint, I get it. Thanks for the explanation.

Yeah, if you don't mind physically swapping the RCA cables, you could do that.

But most of us have our amps, or Home Theater equipment in an entertainment center/cabinet, and it isn't easy to go behind the gear to swap the RCA back and forth between a 2-channel amp/preamp/headphone setup and the 5.1 receiver.

In my case, I keep my home theater setup (dedicated room for only 5.1 channel with Velodyne satellites and subwoofer and 60" screen) separate from my 2 channel speaker setup (bedroom with Yamaha receiver driving Polk SDA CRS speakers), which is separate from my 2 channel headphone setups.

 

[infinitesymphony]

That's what I figured most people did... Either throw all of the money into one main system, or split the tasks into different systems. There doesn't seem to be much difference between high-quality two-channel preamps and HT preamps these days, but I guess we're probably talking about boutique equipment where a given brand may not manufacture a HT solution.

 

[HumanMedia]

Quote:

Originally Posted by infinitesymphony /img/forum/go_quote.gif Ah, okay, I think I understand. I wasn't getting how HT bypass was different from a tape loop / aux. output, or just sending the signal from the A/V receiver's preamp outputs directly to the two-channel power amp. It still seems like unnecessarily complicating the signal path (a lot of extra connections and cabling means more resistance, capacitance, etc.), but from an ergonomics standpoint, I get it. Thanks for the explanation.

I think it actually simplifies things.

It means you can have a high quality stereo audio system and a multichannel system and not have to double up on everything, or switch cables multiple times a day (for me).

Its means I can have a high quality CD player and tubed stereo preamp, high quality left and right speakers and high quality power amps. Then I throw a receiver into that to do the multichannel decoding and power just the center and surrounds.

I couldnt live without it.

 

[sejarzo]

I agree 100% with HumanMedia.....I can only have one room for both music and movies, so the front channels are my music system powered by separates, with an Onkyo HT receiver serving only as a processor plus center/rear amp. Taking the load of the front l/r off an HT receiver is a definite plus in my book, because they're generally current limited.

Seriously.......I had a NAD C320BEE for a few months, and driving my Paradigm Studio 40v3's with no sub in the chain, the low end was more solid than with the Onkyo driving the fronts with the sub in the chain, too!

One could just buy or build an A/B switcher and do without an HT bypass, I suppose, but it is a nice added feature to preamps. When I built a small passive pre/attenuator, it was simple to add a nice quality DPST switch and a set of jacks to provide that same capability.

 

[infinitesymphony]

HT bypass is a more popular feature than I had guessed! I sort of imagined all preamp sections as being equal when this wasn't the case, especially with tube preamps or pre/pros.