Blau Radio/Amp Connectivity

[grsilvia]

Long time reader, first time poster.

'90 C2 Cab with stereo upgrade option. I am replacing the older Sony stereo and CD changer installed by PO with a Blau Alaska head unit and Blau CD changer. The Blau amp under the passenger seat was bypassed, but I would like to incorporate it into the system.
If I understand correctly, the head unit pre out/RCA sends a pre amplified signal to the amp where it is amplified and then sent to the speakers. The head unit is rated at 4X40Watts and the amp is rated at 4X20Watts. Therefore, the total output would be 4X20Watts.
OR, run the speaker outputs from the head unit (post amplified 4X40Watts) to the amp (additional 4X20Watts) then to the speakers=4X60Watts.
Should I use the amp? I'm not looking for thunderous sound, but I would like to take advantage of the amp.
Also, does anyone know what the green wire in the power supply harness does? (4 wire harness, +12V, +12V switched, ground and the green wire)

Lastly, I will be taking the plunge into a top end rebuilt after the holidays. I believe there is a broken stud on #1 and the info provided on this site has given me confidence to go for it instead of paying someone else to have all the fun. Plus my 2 year old son loves to hand me wrenches and get dirty!

Thanks, Gary

[jlr69s]

you cant run the amplified signal from you head unit through the amp to get 60 watts per channel, not how it works. If the Blaupunkt amp uses MOSFET power supply then use the amp power INSTEAD of the head unit power. The amp will give more peak power and even though the head units power is rated higher, the amp will sound much clearer and you will be much more satisfied with the sound. The grean wire is probably the remote turn on wire, it sends to signal to the amp to turn on. You connect that wire from the head unit to the remote turn on terminal on the amp. If you have any more questions about installation post again, I read this BB numerous times a day.

[89911]

I am not sure with you car what the designation is, but on 89 and older it is BRN-ground, GRN-ignition switch, RED-hot all the time, WHT-antenna aplifier. Hope this may help. Also, The amp down there is next to worthless. You could get an inexpensive aftermarket one the same size that will be much more effective and beneficial in making your car sound better. The only connection from the reciever to the amp is a factory patch din cable that won't work with most rca pre-amp outputs, so this may not work anyway. The simpliest way to do this is get a 4 channel receiver deck with 4 preamps out. Run this to a simply 4 channel amplifier and from there, to all your speakers. The original wiring is very good and they make adapters that will allow you to utilize the german pin type speaker connectors to traditional wirings without alterations.

[Roland Kunz]

Hello

The Blaupunktamplifier uses a standard DIN input. 2V signallevel. The connectors pins are according to DIN and not protectet against overload.

Your 40 & 20 = 60 watt calculation is no option it will result in 40 W & smoke/ smell = hot ears & 0 watt

However the Watt things are useless and I´m sick to explain that RMS is nothing exept hot air.
A good in dash unit will make some 8-10 watt max and the rest 30 Watts are only if you short the amp to see the peak power. Has nothing to do with music.
The underseatunit has true 20 Watt sinus thats much more "drive" behind it.

Your local Blaupunkt dealer will have suiting interfaces to run the amp as you wish.

I would bridge the head unit from 4 cannel to two cannel and run the fron speacker while via a interface the rears from the underseat amp.
This will give yo some 20 Watt sinus at all speaker or if you like big numbers 60-70 watts at each speaker.

Before investing in interfaces check if the amp still works and the wires are working as well. Sometimes people hack up the complete electric to install some silly sounding and stupid blinking entertainment center.

I think the green wire was for the radio mute if you had the phone installed.

Not sure with wireloom you have focused. The one behind the dash ?

Grüsse

[grsilvia]

The amp has the DIN input and speaker input, which led me to believe that the radio speaker out could be connected to the amp speaker input. But in the interest of not frying anything, I will use the DIN cable.

The radio will arrive this week and I will try with and without amp (2/4 channel) and go with the better sounding option. I will look into an amp upgrade in the future but being that the car is a Cab I don't expect much from the 5 1/4" and 4" speakers. I occasionally have rear seat passengers so a sub-woofer floor box isn't an option at this time.

Roland: The 4 wire harness is in the dash and the wire colors are brown (-), red (+), smaller gauge red (switched +) and green (?). I've identified all but the green one, but it wasn't attached to anything when I removed the Sony radio. Unfortunately the wires were pretty much hacked up by PO, so my multi-meter will be busy.

Thank you for the replies, Gary

[Rot 911]

Gary, I just installed the Alaska in my 86 coupe. I'm not running an amplifier and have Infinity Kappa 52.1i's in the front doors and Blaupunkt speakers in the rear. The sound is not bad for an inexpensive CD unit. I too thought I would need to run an amp with this unit, but so far have been pleased with the sound. One thing I and other owners have noticed is that the face plate will really get warm. Apparently this is normal for this unit and nothing to worry about. And yes you can use the radio speaker outs for the amp inputs, will not hurt anything. Actually some users of the Alaska prefer using the speaker outs and opposed to the pre amp due to the low output of the pre amp circuit.

[jlr69s]

You can use your speaker wire to give the amp a signal but the amp must have speaker level inputs.

Roland: you [U]can not[U/] bridge the power from your head unit. Doing so would give you a 2 ohm load and head units are usually not stable in two ohm, therfore that will not work. You will fry your CD player!

I wasnt aware that buying an after market amp was in the picture. Do so if you have the money, a great investment!

IMHO Kenwood makes the best multi channel amp. I have two of them and they work wonderfuly, dont over heat and have great power output.

[Roland Kunz]

Hello

@grsilvia

I´m surprised it would be nice to get m,ore informations as the used amp has high voltage input and this is not like they came stock.
The thing is a bit problematic as Porsche used different setups and some radios ( Berlin, Bamberg, Köln, Woodstock, Nashville, Boston )where without build in amplifiers. Yet some people ordered a sound package with a smalll version radio ( with built in 4 x 4 watts ) and they got a booster ( Mostly a BQA/BSA 80 or 107 ) setup. But this setup was only used in pre 89 cars.
A very lucky find would be a rare PSA 108 or 168. Those units came with sound module equipment. You also will find Blaupunkt speakers in the doors and on the shelf ( XL 1300 mdified for Porsche ). The green wire would then be used to have the speedsignal triggered to the amplifier.

However the spaecker input has some resistors turning the engery to heat and will not help gaining signal quality.
Those inputs where integratet to have a larger versalty on stock.
But they are not a real option if you have a RCA or DIN out in the head unit. They are good if you just wan´t to test out a existing setup on the fly.

@Kurt V

Yes the new highpower radio generation has a heat problem limiting the power output. The 10 watts/chanel are working good enough with efficient speakers

@ jlr69s

Yes your are right you can´t bridge high power amps. You have to leave this to an expert or the radio manufactorer.

The problem is you have to separate the signal input from 4 Cannel into 2x2 Channel and have to bridge the amps the correct way. l This solution normaly can´t be done via a interface and there is no marked for it ( amps are cheaper ). But if he reduces the headunit amp load on two channels and leave the others to the seperate amp he will still gain quality and lower the operationtemperature witch will prolong the life from the head unit.

Kenwood are nice products, something like the Toyotas in car audio. Generaly these days the level is very high and even a no name tawan unit will outperform most units made 10 years ago. Mybe not in sound quality and longlivety but who really cares that ? Most will survive the lifecycle from the car.

Grüsse