Question re. front speaker pre-out Pioneer DEH P3500

[donbryce]

Hi all. I'm in the middle of a major install, and have stumbled on a question re. the HU, which has 2 RCA outs labeled in the (so-called) wiring diagram as 'front pre-out' or something like that. On the diagram, it shows a pair of RCA cables connecting these to a separate amp, and 2 'front speakers' coming from the separate amp. On the same diagram, it shows a pair of front and a pair of rear speakers directly from the HU.
There is nothing at all in the user manual about how the amp/speakers connected via these pre-outs are controlled from the HU. Would these be receiving the same signal as the fronts connected directly to the speaker leads of the HU? If I connect the 2 rear speakers instead to the amp from these RCA outs, will I in effect have 4 'front' speakers?

The rest of the system is 2 Infinity 6" components in front, 2 Infinity 6"X9"'s in rear, an MTX 4250D amp and 12" Concept DVC sub, and the other amp (referred to above), an older but great Sansui SMA707 (stereo/bridgable), that I'd like to use to run either the fronts or rears.

[Creedo]

Most every new head unit's packaged with at least one set of RCA preouts, In your case you may have Front and Sub....if so, you want your amp to run off the Sub level outs if possible into the amplifier, and out from there to the sub. >

If you want to amp your front speakers, DO NOT connect them to the speaker wires that come out of the HU too, just run the Front Rca outs to the smaller amp and use that amp's speaker level outputs. You wouldnt want to use both options of wiring (speaker leads and rca ), It wouldnt give you a benifit in any way that i can see, just introduce some problems.

As for the settings in your Head unit for crossover/eq - they opperate both wiring configurations ( using hu for power or rcas w/amp for powering speakers )

[Creedo]

Mis read part - if you ran an amp to anyset it should be the fronts and use the rear speakers off the head units rear speaker outs - the signal will be the same to front and rear, only left and right varies......your fronts would just be a little louder and hopefully clearer off the amp - you 6x9's should only really give you some fill so having them on an amp wouldnt be as beneficial

My theory on wiring them in this way is that it gives you option to set the crossover differently for the front and rear.......if you wired them all as fronts somehow - you wouldnt be able to adjust sound independently.

Sorry about that misread

[donbryce]

Thanks Creedo for your thoughts. I believe you have answered my question about whether the HU controls will operate on the amp running off the RCA front pre-outs ("As for the settings in your Head unit for crossover/eq - they opperate both wiring configurations ( using hu for power or rcas w/amp for powering speakers ))".

And your comments about using the rears for fill are also right on, in that I want to use the external mid/high amp to set up a nice front stage. The Pioneer is extremely complicated (for me) regarding equalizer settings, so I guess I'll have to experiment to find out how to tweak everything when it's all in.

The main thing is that I want to be able to fade the rears lower than the fronts, and have full control over the settings for the front speakers. If the HU controls for front speakers operate with the amp/front speakers from the RCA front pre-outs, as if they were wired into the HU front speaker outputs, then I should be alright.

Only 1 unknown remains, and that is that I don't know the power output of the Sansui amp. The front Infinity's are rated for 90W rms, so if I keep the gain down, say at half, should this be safe I wonder?

[Creedo]

Well there is a proper way to set the gain controls on amps so that you get optimal power to the speakers without making them distort...which is where the damage would occur. I personally have always winged it, which i dont like to do> so lets see who can help us both....

Can someone else chime in with the proper proceedure.....I'm running a separate amp for my fronts along with 2 sub amps ( soon to be matching )....How do you set all the gains correctly?

[donbryce]

Well there is a proper way to set the gain controls on amps so that you get optimal power to the speakers without making them distort...which is where the damage would occur. I personally have always winged it, which i dont like to do> so lets see who can help us both....

Can someone else chime in with the proper proceedure.....I'm running a separate amp for my fronts along with 2 sub amps ( soon to be matching )....How do you set all the gains correctly?

I found this, which is easy enough to understand:
http://p079.ezboard.com/fcaraudiotal...icID=733.topic

...and this, which I haven't had time to digest yet:
http://www.caraudioforum.net/GainSetting.htm