NAD C372 > Dayton DTA-120 > Outdoor Speakers?

[GO-NAD!]

I realize the title may look a bit cryptic, so I'll explain. Right now, I have my kitchen in-ceiling speakers routed through a speaker switch, so that I can run my outdoor speakers (Yamaha NSAW190) as an alternative. Because of their lower sensitivity and being outdoors, I have to raise the volume to the point where it is uncomfortably loud to have a pair of speakers on inside as well.

Anyway, I was pondering this option. The C372 has an extra pair of pre-outs - "Preout 2". I can install another amplifier, such as the DTA-120, to power the outdoor speakers. Pre-out 2 is controlled from the main volume control, so the voltage varies with volume (If I understand correctly). So, with the main volume down at a comfortable level inside, will there be sufficient voltage to drive a DTA-120 for the outdoor speakers? The gain on Pre-out 2 can be adjusted, but downwards only, i.e. at max the gain is the same as the normal gain of the C372.

I hope I've explained my query at least somewhat clearly.

 

[jotham]

I realize the title may look a bit cryptic, so I'll explain. Right now, I have my kitchen in-ceiling speakers routed through a speaker switch, so that I can run my outdoor speakers (Yamaha NSAW190) as an alternative. Because of their lower sensitivity and being outdoors, I have to raise the volume to the point where it is uncomfortably loud to have a pair of speakers on inside as well.

Anyway, I was pondering this option. The C372 has an extra pair of pre-outs - "Preout 2". I can install another amplifier, such as the DTA-120, to power the outdoor speakers. Pre-out 2 is controlled from the main volume control, so the voltage varies with volume (If I understand correctly). So, with the main volume down at a comfortable level inside, will there be sufficient voltage to drive a DTA-120 for the outdoor speakers? The gain on Pre-out 2 can be adjusted, but downwards only, i.e. at max the gain is the same as the normal gain of the C372.

I hope I've explained my query at least somewhat clearly.

I read your manual and they hint at the right approach for you in the Bi-amping approach. Both Pre1 and Pre2 are controlled by the volume knob. Neither are a set level. However, Pre2 has the addition of the gain control which only minimizes gain.

You would probably be fine with either but due to your description, I recommend the following config.
Pre1 ->outboard amp (DTA-120) -> yamaha outdoor speakers
Pre2 -> NAD amp (main) -> inside speakers.

This way, you will have plenty of gain for the less sensitive outdoor configuration and you can reduce the gain appropriately for the inside speakers using the trim knob.

good luck!

 

[ski2xblack]

Typically, one would use the second set of pre-outs in a bi-amp configuration, using the adjustable pre-outs on the amp with the highest voltage gain. They're handy if you want to insert an active crossover/eq etc. For your case, consider using the fixed pre-outs with the Dayton, and the adjustable with the build in amp: full hot signal to the Dayton->outdoor speakers, less hot pre-outs going back into the NAD so as to not overly blast the inside system when you're using the outdoor system. [edit. Jotham beat me to it]

Also, the pre-amp stage of the NAC C370 runs notoriously hot. Poorly ventilated units will cook themselves to death eventually, and while replacing caps is not terribly expensive, it's a hassle that can be avoided. With mine, I use a 3V-12V converter plugged into the accessory AC on the back of the amp, which is connected to a fan I keep on top of the unit. At 4V it is dead silent, and moves plenty of air. Total cost about $5. Cheap peace of mind.

 

[GO-NAD!]

Right now, Pre-out 1 is routed through the DCX2496. I never thought about going through Pre-out 2 and using Pre-out 1 for the other amp. That would probably work, but I'm not sure I want to have go in behind and fiddle with the gain whenever I'm using/not using the outside speakers. I guess I can't have it both ways though, eh?

Also, the pre-amp stage of the NAC C370 runs notoriously hot. Poorly ventilated units will cook themselves to death eventually, and while replacing caps is not terribly expensive, it's a hassle that can be avoided. With mine, I use a 3V-12V converter plugged into the accessory AC on the back of the amp, which is connected to a fan I keep on top of the unit. At 4V it is dead silent, and moves plenty of air. Total cost about $5. Cheap peace of mind.

Thanks for the tip. I know it gets pretty warm and I have thought about installing a fan, but that's as far as I gotten with that idea.

 

[agarwalro]

Right now, Pre-out 1 is routed through the DCX2496. I never thought about going through Pre-out 2 and using Pre-out 1 for the other amp. That would probably work, but I'm not sure I want to have go in behind and fiddle with the gain whenever I'm using/not using the outside speakers.

The gain on the Pre1 is probably matched to the amp input and the Pre2 has a gain knob to ensure an external device's input is not clipped (since NAD cannot predict what will be plugged into that output, amp, recording device, active monitors, etc.). You will in fact need to use the gain knob to ensure your DTA 120 or any other amp input is not driven to clipping.