View Full Version : Need advice on my mono amp

10-06-2003, 09:34 AM
Hi, I need some advice from someone knowledgeable with mono amps to help me with a confusing issue.

My system's pretty low-key, and I'm far from being an audio expert so please bear with me... Here's my current setup to clarify the situation:

Clarion HX-D10 CD tuner === Sony XEC505 in-dash X-over === Nakamichi PA-304 4-channel amp (running 30W x 2 + 90W x 1) === Nak SPS-510 5 1/4" separates + Solobaric 10" in sealed enclosure.

I just got a used Nak PA-301 mono amp (rated at 160W) so I can bridge the PA-304 to 90W x 2 to drive a pair of Diamond Audio separates that I plan to get soon (needs more than 30W to drive them). I was assuming the PA-301 would be your basic 2-in 1-out mono amp but it turns out it has outputs for 2 subs (4 terminals, 2 plus and 2 minus), and THERE IS NO BRIDGE SETTING. I only have one sub, and I'm wondering, if I hook it up to only one pair of terminals, will I still get 160 watts (Conversely, say if I had a pair of subs, if I hook them up to both pairs of terminals would I then end up with only 80 watts driving each speaker)? And which set of terminals should I be hooking my sub up to in order to get 160 watts?

As I got it through an auction it didn't come with a manual, and now I'm worried that I just wasted my money on the wrong type of amp :( (perhaps I shoulda gotten a PA-302 80W x 2 amp to bridge to 160 x 1).

Has anybody had experience with this sorta setup? Does anybody happen to have a PA-301 manual lying around (yeah, right)? Does anybody even know what I'm talking about?!


10-06-2003, 11:22 AM
Have you emailed the company to get specs on the amp. Usually you tap in to (+) outputs on both left and right channels for it to bridge (not using the (-) outputs), but I would suggest emailing them www.nakamichi.com and asking for their input to make sure that it is okay to do so. On my Soundstream, there are plastic pieces on the back that pop off revealing a switch mono, stereo, mixed mono.

10-06-2003, 04:06 PM
Actually to bridge, you usually use one channel's (+) and the other channels's (-). Nto sure which channel would be which on that amp though. DO you have any pics of the amp and the connections to it?

10-06-2003, 04:08 PM
how to bridge on all amps are different, but it usually says which terminals to use on the amp itselt.

blue LEDz
10-06-2003, 04:53 PM
if the speaker terminals are in a line, you usually have to connect the speaker wire to the outermost terminals;) it should have an internal bridge setup, for if you connect 2 subs to it, which you don't need to worry about:biggrin: but don't worry, the amp will work fine for you. are both your amps, 301 and 302, the same dimensions? they are probably the same casing, so it'll have the 2 sets of outputs to keep the production costs down from not having to change the case;)

btw, sweet car:biggrin:

10-07-2003, 09:26 AM
Thanks for all the input, guys. Really appreciate it.
You'd think there was some way to bridge it using the terminals (outermost makes sense, based on my limited experience with other amps), but then again maybe "bridging" isn't really part of the deal...I mean, it's a mono amp to begin with, so what need is there to "bridge" any signals? :confused:
I'm just hoping I can get the full 160 watts out of this amp...
Anyway, I've taken Mister T's advice and emailed Nakamichi.com with my question. Hopefully they'll be nice enough to respond...
I'll keep you posted just in case there's interest. Thanks again!

10-07-2003, 09:55 AM
Like BLue said, it is the outer most outputs. I was looking at my SoundStream amp and wanted to clarify that. I would think that this would work, but would wait to hear from Nak before doing it just to ensure that nothing happens. Hopefully Nakamichi will be more informative about their amps than Soundstream is:rolleyes: SS makes great products, but they are lacking in customer support.

10-07-2003, 12:23 PM
Well, going back and looking at the JBL amp that I just sold to MisterT, it also had two sets of speaker outputs. It gave two outputs to facilitate wiring more than one woofer. I would just tryt o use one of the outputs first, if you don't hear back from Nak.

10-07-2003, 01:30 PM
Thanks, you guys are great.
I'll let you know what they say, if they reply.

10-10-2003, 01:26 PM

I took MisterT's advice and contacted nakamichi.com and they were nice enough to advise me the next day that you don't have to "bridge" by using the (+) terminal of one channel and the (-) terminal of the other after all. You just use the left channel outputs (go figure), and you get the full 160 watts. AND they were nice enough to attach a PDF file of the manual! Great support.

Thanks for all the input guys. If I have any more Qs about car audio, I know where to go!

10-10-2003, 02:06 PM
Originally posted by Rider69
Well, going back and looking at the JBL amp that I just sold to MisterT, it also had two sets of speaker outputs. It gave two outputs to facilitate wiring more than one woofer. I would just tryt o use one of the outputs first, if you don't hear back from Nak.

So you don't recommend running it Bridged, but to run each sub to each output? Right now I have it bridged. That amp is nice too! I like the illumination around the JBL logo on the amp. I just have a little more tweaking to do. Lights still dim however, but not sure if it is as bad as when the SoundStream was in. A cap won't do much, but after work, i am going to put the cap back in to the car to see if it helps with the little bit of dimming it was doing. The A/C was off and it would dim, but the fan was on. More tests to come tonight.;)

10-10-2003, 02:35 PM
MisterT, yes, bridge your speakers. There should only be one set of wires going to the amp. It is fine the way you have it.

Oh, and go figure, was testing out my system the other day in the garage and wouldn't you know it, I noticed a little bit of a dim when the bass hits. I will have to work on that.:mad:

10-10-2003, 10:02 PM
With the JBL, I still get dim, but not as bad. I crossed it over at 80 Hz instead of 125, and that seemed to help as well as retain some punchiness in the bass:p: Only at loud volumes, it will dim enough to notice, but with the SoundStream, it dimmed even at moderate levels. I got the 1.5 farad cap back in and it may help it some:rolleyes: I should have gotten four 8 ohm 10's;) imagine the space that would take up though! :eek: You should hear the EDs in the box Blue built. It hits really hard and sounds good with all types of music. A little trickier tweaking than a simple sealed, but hey, once you get it on, you are right on!:40oz: