Output connections from NOS1

[Robert]

I currently run the output from DAC through my preamp(7.1 inputs, sound is only running through volume pot). I'm keen to upgrade to the NOS1. I will need two sets of outputs one to the power amps and one to the active subs in order to remove preamp from circuit. I would prefer this over splitting signal with a Y splitter. Possible?

Robert 

[PeterSt]

Hi there Robert,

First response : very well possible. The NOS1 has two sets of outputs in parallel (both active at all times). Normally one set is XLR and one set is RCA. But any combination is customizeable for you easily. However :

There are a few things which make me think this is not the best way to do it. I mean, not when I'd like to kind of guarantee the best SQ possible, which otherwise will be the most hard to judge in advance. This is about the different reactance your subs may have compared to the normal main amp(s). So, although maybe minimal, both may react at different times, and depending on the music (frequencies) there even may occur "resonance" which is the worst (because that will create a frequency within itself *and* riding along with the beat of the music). Remember, maybe.

What I would prefer is satelliting your subs from the LS outs on your main amps. Now there's only one normal reactance with its own characteristic (which of course nobody knows again) which at least won't be influenced by another one.

What this officially takes is a "high level" input on your subs (many have that), but if that is not possible it can be tweaked into that fairly easy. Another thing is that this kind of connection is just way better in general (higher current). You will perceive this is as more powerful. More tight.
You can try this right today of course (when the inputs are there, and then without further hassle).

Let me know any further thoughts !
Peter

[Robert]

Hi Peter I've now connected my subs via the amplifier outputs. I had to make up a voltage divider to reduce output. Sub settings have all changed now.
I agree with you there is a better synergy of sound now. I'm running the subs crossed over at 40hz.
This is very similiar to the Rel connections I use to run.
I also have to report the Young Hitech software is better than the standard software and worked fine in my setup. I've also tweaked Benchmark some more.
All adding up to a major sound improvement overall.
Thanks for your input.

[AlainGr]

Hi Peter,

My question will be off topic, since I do not own an NOS1, but the subwoofer part is of interest for me.

I have 2 Tannoy subs (TS-1001) and they allow either an RCA connection (low current), or the possibility to connect from the line out of the amplifier. I did not read much about the latter.

As for the former, I have 2 pairs of outputs from the preamp, so I use one pair for the amplifier (then the speakers), the other pair is used for the subs...

I am not sure which could be the best ? From what you answer here, it looks as if it would be better to use the same line as for the speakers ?

Thanks,

Alain

[Robert]

Definitely try running subs from amplifier outputs. Read up on how REL connect subs(www.sumikoaudio.net/rel/manuals/REL-SET-UP.doc). This means you run your loudspeakers full range from pre-amp/power amp and subs from the amp outputs which is the same signal as the mains get.

It does help to better integrate subs with main speakers.

Your subs need to be active and have adjustable crossover points and volume. It takes some practice to get these correct over time.

[AlainGr]

Hi Robocop,

Thanks for the answer. Yet I am still wondering how the amplifier inside the sub kicks in when we use the power amplifier mains output ? Is the signal attenuated, then re-amplified again ?

EDIT: I am reading the article about the REL... It explains what I was wondering.

And is it recommended to have the same cable length between PA and subs (same lenght as the mains) ?

Finally, is there a "power drain" with this type of connexion ?
EDIT: It is answered here too :-)

Alain

[Robert]

I do run the same length cables but its not a major issue as long as its not very long lengths. I would try it with what ever you have got to start with.

No power drain but you are running the bass signal through a second amp(Sub). I think the integration advantage far out ways the disadvantage of the signal running through the second sub amp.

Mine is crossed over at 40hz now volume at 12 oclock. This will not have any relevance to your setup.

This site shows what I have done and also the reason I bought these subs over the REL's: http://www.10audio.com/jlaudio_f112.htm

Robert

[AlainGr]

Hi Robert,

I read the second article (F112 Audio Fathom) also and found it very interesting. I can just imagine what you perceive with such a powerful and fine subwoofer(s ?) !

Mines do not have adjustment knobs, instead all is done through a small LCD screen. Alas it does not allow fine tuning, except in jumps of 10HZ at a time. The crossover adjustment does not go below 50HZ (mains speakers are going down to 38HZ and surprisingly they do not deliver powerful bass in general). Since I only use my sound system for music, I did not have the intention of getting a sub (2 in fact). They are rated at 300 watts, but for what I do they are sufficient. I just want to extend the LF but with not too much presence.

I will try it as soon as I can put my hands on cables. I actually have a "quad" cable (bi-wiring) and I do not have 2 pairs of mains out... But I will try it in hope it will blend better with the mains, even if I have no real complaint about the way they actually are connected. I am not sure I have the hearing abilities to discern at this level, but it certainly does not cost much to try :-) And it's fun too !

What conducted me in that direction recently is the fact that I have 2 supertweeters over my mains and there was something wrong but I could not put my finger on it, until I started questionning the positioning of my ST. I started moving them .5 cm at a time and suddenly something blended a lot better... I remembered then that it was possible to connect the subs directly to the amplifier... Do I am curious.

Thanks again !

Regards,

Alain