[Ultralight]

Current setup that's pretty intuitive: Laptop > USB DAC>Integrated tube amp>Speakers

Now I'd like to add a self powered subwoofer in the chain.  How do I add a sub in terms of connects and also have the signal to the speakers cut off below 80hz?  Do they make a USB DAC with dual output - one for sub, and one to put into tube amp which will then power the speaker - AND with the signal cutoff below 80hz?   If not, how do people add subs?

Don't want to take the signal through the sub and then take the signal out as that degrades the signal a bit per the sub manufacturer. 

Thanks,
UL

 

[TJHUB]

You can't add a subwoofer to a DAC because you wouldn't have volume control over the sub.  I don't think you can do it with an integrated amp.  I do it with my preamp, but that's because I can add devices between my preamp and amps.  What outputs and inputs does your integrated have on it?

[JRace]

Which integrated amp do you have?
Which sub?
What speakers?

You must run the audio signal through a crossover in order to cut out the sub freq from your mains.

You either, run line-level (pre-outs / RCA) to an external crossover, then run the lowpass to the sub and the high pass to the speakers, or you run speaker wires to the sub, and then hook the speakers to the subs hi-pass outputs.

Alternatively you could run line-level (pre-outs / RCA) straight to the sub and leave the mains full range.

[Ultralight]

The original setup is:

Laptop > HRT Music Streamer II DAC (pair of RCA output) > Miniwatt N3 tube amp > speakers.

The sub could potentially be a Emotiva subwoofer.

So I need a crossover?  I wasn't aware that they even made something like that. Any brand suggestion?  I assuming that adding a crossover unit will impact the sound negatively if one listened carefully?  What type of crossover or brand?

Thanks in advance for any further help.

Thanks,
UL

[Tone Depth]

The easiest way to do it is to get a sub powered by an integral plate amp that has a high level bypass.  The plate amp has the crossover you need.  Wires go from the DAC to the sub amp inputs, then from the plate amp high level bypass outputs to your tube amp inputs.

The original setup is:

Laptop > HRT Music Streamer II DAC (pair of RCA output) > Miniwatt N3 tube amp > speakers.

The sub could potentially be a Emotiva subwoofer.

So I need a crossover?  I wasn't aware that they even made something like that. Any brand suggestion?  I assuming that adding a crossover unit will impact the sound negatively if one listened carefully?  What type of crossover or brand?

Thanks in advance for any further help.

Thanks,
UL

[TJHUB]

The original setup is:

Laptop > HRT Music Streamer II DAC (pair of RCA output) > Miniwatt N3 tube amp > speakers.

The sub could potentially be a Emotiva subwoofer.

So I need a crossover?  I wasn't aware that they even made something like that. Any brand suggestion?  I assuming that adding a crossover unit will impact the sound negatively if one listened carefully?  What type of crossover or brand?

Thanks in advance for any further help.

Thanks,
UL

You can't really add a sub with your current integrated.  Most subs only have low-level (RCA) inputs (like the Emo subs).  You would have to feed the signal to the sub from a pair of pre-outs on your integrated.  Your integrated doesn't have any outputs.  Can't be done.

Your ONLY option with your current integrated is to find a sub that has high-level speaker inputs.  This would allow you to connect the speaker outputs from your integrated to the sub's speaker level inputs.  However, I think most of those subs will not high-pass your main speakers, so they would be running full-range.  This is not a crime in some cases.  It really depends on how capable your main speakers are for bass and how they are reacting with the room.

My suggestion is to try a sub with speaker level inputs and give it a try.  If you want something more serious, then you need a different integrated amp with more features, or a separate preamp/amp setup. 

What speakers are you running? 

[srb]

Another option with your existing amp, which would also result in running your mains full-range, is to use a subwoofer like the REL that connects in parallel to your main speakers at the amplifier's speaker terminals with a special high impedance connection.
 
Although your mains would still be running full range, it is a purer connection that doesn't require routing the amplifier's outputs through a subwoofer's speaker-level inputs and then on to the speakers.
 
Steve

[Elizabeth]

Expensive answer is to buy a sub crossover, like a Bryston 10b. $$$$
The cheap answer is to run the sub off your amp and ignore a crossover. Your speakers are not going to put out much in that range, and you can adjust the sub to be a good balance.
The  REL mentioned by srb is a good idea.

[Jazzman53]

A "Mini-DSP" crossover might be a good option and it doesn't cost much.

[Ultralight]

Everyone, HUGE THANKS!   Wow - what a great forum.  I consider myself a newbie and having a newbie forum is something I've never thought of - but makes perfect sense and I am grateful for all your help.

The most valuable part of all your answers is that I feel I have received a good sense of the RANGE of possible solutions - along with the limitations of each solution.

A couple of comments:

1. The cheapest sub I found that I consider to be good quality for music reproduction is the Rythmik F12 which does have high pass and low pass so it would work, to pass the signal with low frequencies filtered out, to the tube amp.   It's still not cheap at $800 or so.  The problem with this approach is the increased grain in the signal as reported by some user.  Basically there's a hit in the quality of the signal when passed through the Ryhmik crossover.    Question of course is how much - no idea on that

2. MiniDSP   Wow!  Never even dreamed something like this existed.  Pretty amazing - looks like exactly what I need for under $200.  The question remains how much audio quality takes a hit being put through the processing.  The flexibility and power of this little thing is amazing.    Thanks for the posting.  I'll have to look at it more.

Thanks!!

UL

[JLM]

The Rythmik sub should be good and are sold direct by Ascend Acoustics.  BTW I love my Ascend Acoustics CBM-170's (original models).  I used them with a sub in a 2.1 audio/HT system for several years, now I've added a HTM-200 center channel and built-in rears for my dedicated HT.

Content value is extreme (but standard cabinet finish is poor), dynamics, tonality, and imaging are all very good.

[wgscott]

I know nothing about subwoofers, but occasionally wonder if my two-channel system might benefit from this.

Is there any reason why one can't simply run a pair of speaker wires from the main speaker to the sub's high-impedance speaker wire in?  In other words, is there any disadvantage to having wire going from amp to speaker to sub, vs. two parallel sets of wires going from the amp to each?