Bridging NADs

[Dogsnif]

Hello all. My first post, so bear with me. I will very soon take possession of two NAD 214 Amplifiers. They will join a NAD 7155 Integrated Amp and a NAD C541i CD Player. I am currently driving either JBL Studio 230s or KEF Q Compacts as well as a Definitive Technologies 200TL powered sub.

My question is can I bridge the 214s and use the 7155 as a preamp? And, if so, how do I go about wiring it up. The NAD manuals aren't the clearest things in the world when it comes to bridging anyway. I keep looking for a diagram (a picture is worth a ....) but cannot find one specific for my needs.

I noticed several postings on this site about bridging NADs with Maggies(?) but they didn't seem to apply to my situation. Any help is appreciated!

[Feanor]

Hello all. My first post, so bear with me. I will very soon take possession of two NAD 214 Amplifiers. They will join a NAD 7155 Integrated Amp and a NAD C541i CD Player. I am currently driving either JBL Studio 230s or KEF Q Compacts as well as a Definitive Technologies 200TL powered sub.

My question is can I bridge the 214s and use the 7155 as a preamp? And, if so, how do I go about wiring it up. The NAD manuals aren't the clearest things in the world when it comes to bridging anyway. I keep looking for a diagram (a picture is worth a ....) but cannot find one specific for my needs.

I noticed several postings on this site about bridging NADs with Maggies(?) but they didn't seem to apply to my situation. Any help is appreciated!

Bridging the 214 is a simple matter but beware that bridging should only be used (in case of the 214) with speakers whose impedance is 8 ohms or higher. I see that both the JBLs and the KEFs are 8 ohms, so no problem;

Here is a picture of the rear of the 214. With the amp off and the speakers disconnected, first move the 'Bridge Mode' switch from 'Off/Stereo' to 'On/Mono', then connect the both speaker cable connectors from a single speaker to the RED speaker output connectors, i.e. cable end '+' to the indicated '+' Red speaker output, and '-' to the '-' Red output as indicated on the amp.

9994

[Dogsnif]

Thanks so much for responding Feanor! I'm assuming that the Left RCA output coming from the Pre-out on the 7155 would go to the Left input on 214-A and the Right RCA output would go to the Left input on 214-B per the attached crude diagram. 9995

[Feanor]

Thanks so much for responding Feanor! I'm assuming that the Left RCA output coming from the Pre-out on the 7155 would go to the Left input on 214-A and the Right RCA output would go to the Left input on 214-B per the attached crude diagram. 9995

Yes, that's right. Per the instruction on the rear of the amps themselves, the both the Left and Right outputs on the amps go the Left (Mono) input on the respective amps.

[Dogsnif]

Yes, that's right. Per the instruction on the rear of the amps themselves, the both the Left and Right outputs on the amps go the Left (Mono) input on the respective amps.

Thanks again. I noticed that your system configuration shows that you run your subwoofer off of your preamp but I don't know if your preamp has a dedicated sub channel. I'm wondering if I can do the same by running my sub off of the NAD 7155 that does not have a separate sub channel.

[Feanor]

Thanks again. I noticed that your system configuration shows that you run your subwoofer off of your preamp but I don't know if your preamp has a dedicated sub channel. I'm wondering if I can do the same by running my sub off of the NAD 7155 that does not have a separate sub channel.

Yes, you can provided your sub has stereo, (i.e. both Left & Right), RCA input connectors as most do, (and not just one, 'LFE' input). You will run interconnect cables from the Preamp output on the 7155 to you sub, BUT since the 7155 has only one set of Preamp outs, you will need a 'Y' connector to divide the outgoing signal between you power amps and the sub.

Here is a type of RCA 'Y' adaptor: you need a Left and a Right; each has one male input plug, (goes to the 7155 Preamp out), and two female output, (attach one interconnect for the power amp and one for the sub) ...

http://www.parts-express.com/data/default/images/catalog/120/091-515_HR_0.jpg http://www.parts-express.com/data/default/images/catalog/120/091-510_HR_0.jpg

This is another design of 'Y' adaptor that does the same thing ...

https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcQSvHzPIhEM-63GofBwZ30pF840EpR5yJBkaUg2DqdemvF3FRXR_Q

[Dogsnif]

Thanks for your patience. I was wondering why I couldn't just use the unused 7155 speaker connections straight to the sub but I figured that's what the manual was talking about when it says that the Pre-out controls the front panel and the Main-in controls the speakers. Duh! I guess what lead me to the thought of using the unused speaker terminals is that when I use my tube amp (Yaqin MC-13s) I use banana plugs for the main speakers and then double up with spade connecters to send juice to the sub. I've got to stop thinking so much!

[Feanor]

The Main-Ins supplies signal to the 7155's built-in power amp; if you disconnect them from the Pre-Outs no signal goes the the 7155's power amps so there will be no signal coming from its speaker connections.

Of course you could use a 'Y' connector to feed both the external power amps and the 7155's Main-In, but it would be better, (if using a 'Y' connector), to directly feed the sub's Line-level RCA inputs.

[Feanor]

Thanks for your patience. I was wondering why I couldn't just use the unused 7155 speaker connections straight to the sub but I figured that's what the manual was talking about when it says that the Pre-out controls the front panel and the Main-in controls the speakers. Duh! I guess what lead me to the thought of using the unused speaker terminals is that when I use my tube amp (Yaqin MC-13s) I use banana plugs for the main speakers and then double up with spade connecters to send juice to the sub. I've got to stop thinking so much!

If you have interconnects from your 7155's Preamp Out connectors to your external power amps, then the 7155's internal power amps aren't getting a signal and, accordingly, the Speaker outputs can't pass a long a signal to your sub.

[bfalls]

How disappointing. From the title I thought this was another sex ad:-)

[Dogsnif]

How disappointing. From the title I thought this was another sex ad:-)

Too funny!

[Jaguar]

I bridged a pair of 3020's early in my audiophile experimenting, but never got good sound.

[blackraven]

is any one having trouble posting? AR has been wonky this week