DHD amp in tri-mode

[NicoB16A2]

Hi. I own a DHD NTX-2008 4ch amp, and... no owner's manual!!

I need to connect it to 2 speakers and one sub (tri-mode). I attach a pic of the speakers connectors. Should I use channel 1 and 2 for the speakers and bridge 3 and 4? Also, I'm not sure how to bridge it (no manual or schematics!). As you can see in the pic, some of the connectors are circled, it would look like those are the one to use in bridge mode. Would that be a correct asumption? Anybody has a DHD amp to help me?

Also, in the back panel there is another switch which reads "Mode 2-3-4". Should I select "3" when running in tri-mode? If I do, should I bridge 3 and 4 or 1 and 2? If anybody has a DHD amp, your help is appreciated!!!!

[NicoB16A2]

back panel...

[lloyd_nickens]

run spkrs off ch 1 & 2 and run subs off ch 3 & 4 (bridged). set the mode to 3.

[PaulD]

what you want to do is NOT tri-mode .... but it sounds like lloyd has got it figured out for you.

[NicoB16A2]

Thank you all. As soon as I finish the sub enclosure I will try it out.
Anyway, I would like to know what the "Mode 2-3-4" really do.
Also, when in bridged mode, does the single sub get signal from both the left and right channel?

[PaulD]

mode 2 = front L&R bridged AND rear L&R bridged
mode 3 = front L&R in stereo, rear L&R bridged
mode 4 = all channels in regualr mode (a 4 channel amp)

yes, bridging ads the output waveforms of the two channels to make a single channel that has (in theory) twice the power.

[lloyd_nickens]

thanks paul, i haven't been on in a while. and yes what i wrote wasn't tri-mode. it looks like that amp isn't actually capable of tri-mode operation.


[edit] i looked into it a lil more... theoretically you could get any amp to run in tri-mode. but it would require high impedance (8 ohms +) speakers for amps not designed to run under 4 or 2 ohms...

[NicoB16A2]

Well I hooked everything. Channel 1 & 2 to front left and right signals, and Channel 3 and 4 to rear left and right signals. Channels 1 and 2 drive the front speakers, and channel 3 and 4 are bridged to drive the (single) amp.

I had to set the amp in "Mode 4" (and I still not sure what that exactly does), because setting it in "Mode 3" only got bass signal from one channel (right). When setting the balance all the way to the left, no bass signal was heard. In mode 4, whether I pad to left or right, bass signal is allways there.

Thanks to all of you.

Nicolás

[lloyd_nickens]

hmm thats odd. there is the possibility that mode three and four were reversed (as in our explaination of it).

[Rich]

Ive also seen some amps that when set to drive a sub, they just take 1 of the channels and use it, instead of bridging them together and making a mono signal out of it.

My 2ch amp does this. When set in mono mode, it only uses the signal from the Lch.

[NicoB16A2]

Originally posted by lloyd_nickens
hmm thats odd. there is the possibility that mode three and four were reversed (as in our explaination of it).

I don't think it was reversed, because I used it in mode 4 driving 4 speakers for 2 or 3 months with no problems.
Well, I seems to be working now but I sure would like to get a hold on the users manual. If somebody ever reads these and has a DHD amp, scan the user manual for me!