Blaupunkt bremen sqr with 6 speakers

[borisca]

Hello,

I'm a total noob so please forgive me if this is stupid.
I own a 1989 XJ40 daimler with 4 speakers in the doors and 2 speakers under the back seat for a total of 6 speakers.

Last year i repaced the ugly pionner with a blaupunkt bremen sqr 46.
Speakers are stocks

The description of the blaupunkt bremen state :

AMPLIFIER
Number of channels: 4
Max. Power: 4 x 50 Watt
Sinus power at 14.4 V: 4 x 24 Watt (DIN 45324)

OUTPUTS
Loudspeaker (number of): 4
Pre-amplifier (channel): 4 (Cinch)
Pre-amplifier (voltage): 4 Volt
Variable amplifier delay time: yes
Sub-Out: yes (Cinch, var. gain/frequency)

I replaced the pionner with the blaupunkt and the 6 speakers are working fine, but as they are old, I'm in the process of replacing them. I already change one speaker in one door and so far it's working.

stock speakers on the door are 4 inch (8ohm) and I'm replacing them with Rockford Fosgate Prime R14X2 4inch (4ohm)

My question :
Should I worry with the ohm difference ?
Why does the blaupunkt bremen say it's 4 channels but there is 6 speakers ?
Can I damage something ?

Thanks in advance and let me know if you need more detail

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edit 1 : I found this which explain the 4 channels/6 speakers, right side is mounted together as well as left side, only the speakers under the back seat are alone (see attached picture)

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edit 2 : Blaupunkt responded to me about the speakers compatibility (autoradio) :

"Please note that the impedance must not fall below 4 ohms per channel - you must not connect two speakers in parallel to one output channel under any circumstances."

After reading the diagram, it looks like the speakers are connected in parallel (correct me if I'm wrong),

series connection : If both of the speakers have an impedance of 4 ohms, the total impedance will be 8 ohms.
parallel connection : If you have two 4 ohm speakers connected in parallel, the total impedance is 4/2 or 2 ohms.

Series Parallel Speaker Impedance

This page of the bcae1.com site covers series/parallel resistance a bit more in-depth than the previous pages. Here, you will learn to connect your speakers so that the ohm-load is safe for your amp.

www.bcae1.com

which means I will toast my autoradio if I plug all my 4 ohm speakers in the car, can someone confirm please ? thanks you

Click to read more...

 

[1aespinoza 10+ year member]

which means I will toast my autoradio if I plug all my 4 ohm speakers in the car, can someone confirm please ? thanks you

That diagram is showing a 6 channel output. The Lefts are sharing a ground as are the Rights. The subs are on their own channels. That makes them all a 4 Ohms load per channel. Are the fade and balance working as they should, and are subs playing? If yes, do the subs fade and sway left to right?

 

[borisca]

That diagram is showing a 6 channel output. The Lefts are sharing a ground as are the Rights. The subs are on their own channels. That makes them all a 4 Ohms load per channel. Are the fade and balance working as they should, and are subs playing? If yes, do the subs fade and sway left to right?

Thanks for the response, yes everything is working with the stock speakers (balance, fade, subs, left to right). The only issue I fear is that the stock doors speakers are 8ohms while my replacement are 4ohms, Blaupunkt said I cannot go under 4ohms per channel.
I'm still unsure if the doors connection are in series or parallel, I fear that if I plug all the doors speakers with my 4ohms i will get 2ohms in 2 channels (bass speakers are ok in this scenario)

What do you think ? Will this work or I will kill my autoradio ?
thanks

 

[1aespinoza 10+ year member]

What do you think ? Will this work or I will kill my autoradio ?

So when you fade to the rear, do only the subs play? If yes, then the front channels may be connected parallel. That would explain the 8 Ohms speakers. I would not use 4 Ohms speakers in that case.
If you cannot find 8 Ohms speakers, you could wire in parallel a load resistor to bring up the impedence. I do not know how much power will be lost if any, but it will raise the safety margin.

 

[borisca]

So when you fade to the rear, do only the subs play?

I will try that when I get back home

If you cannot find 8 Ohms speakers, you could wire in parallel a load resistor to bring up the impedence. I do not know how much power will be lost if any, but it will raise the safety margin.

I'm also wondering if I can directly change the wiring from parallel to series directly on the back of the autoradio.
Also, maybe installing a small amp with 6 channels at 4 ohms would solve the issues. I have no idea what to expect in terms of work load/difficulties

edit : wow, those amp are expensive !

 

[1aespinoza 10+ year member]

I'm also wondering if I can directly change the wiring from parallel to series directly on the back of the autoradio.

This would be counterproductive, your radio would see an 8 Ohms load instead of 4 Ohms. That would halve the power output.

Also, maybe installing a small amp with 6 channels at 4 ohms would solve the issues.

You would be fine with a four channel. Most amps can handle 2 Ohms per channel. So the 4 inch speakers parallel in the front channels and the subs in the rear channels.

I have no idea what to expect in terms of work load/difficulties

edit : wow, those amp are expensive !

The most technical part would be wiring into the radio harness to power the speakers. This way eliminates the need of running wire to individual speakers. The Blaupunkt should have RCA outputs, those would feed signal to the amp.

 

[borisca]

You would be fine with a four channel. Most amps can handle 2 Ohms per channel. So the 4 inch speakers parallel in the front channels and the subs in the rear channels.

so I will be using 3 channels out of the 4 channels right ?

channel 1 : front right door + back right door (total of 2 ohms)
channel 2 : front left door + back left door (total of 2 ohms)
channel 3 : 2 x bass speakers (total of 2 ohms)
channel 4 : unused

or

channel 1 : front right door + back right door (total of 2 ohms)
channel 2 : front left door + back left door (total of 2 ohms)
channel 3 : 1x bass speakers (total of 4 ohms)
channel 4 : 1x bass speakers (total of 4 ohms)

 

[1aespinoza 10+ year member]

channel 1 : front right door + back right door (total of 2 ohms)
channel 2 : front left door + back left door (total of 2 ohms)
channel 3 : 1x bass speakers (total of 4 ohms)
channel 4 : 1x bass speakers (total of 4 ohms

This one. If the full ranges overpower the subs, you can just fade rearward.

 

[borisca]

thanks man

do you think something like would do the job ?

Clarion XC2410

Compact 4-channel amplifier — 50 watts RMS x 4

www.crutchfield.com

(kudos because it's compact)

• 4-channel amplifier
• 50 watts RMS x 4 at 4 ohms (75 watts RMS x 4 at 2 ohms)
• 150 watts RMS x 2 bridged at 4 ohms (4-ohm stable when bridged)

the speakers are rated at 30 watts RMS

I have no idea what is happening to the wattage when they are in parallel, do they become 60 watts RMS (30x2) or they stay at 30 watts RMS ? (yeah I'm a noob)

I'm struggling to find a amplifier with 4 channel : 2x 2ohms, 2x 4ohms rated 30watts RMS.
they are all 100 or 150 watts...

 

[1aespinoza 10+ year member]

do you think something like would do the job ?

Yes.

I have no idea what is happening to the wattage when they are in parallel, do they become 60 watts RMS (30x2) or they stay at 30 watts RMS ? (yeah I'm a noob)

Just like the ratings say. Most amps double in output when resistance is halved. Since that amp is a compact, it does not double but still goes up. So each speaker on the paralleled channels will get ~37.5 watts.

I'm struggling to find a amplifier with 4 channel : 2x 2ohms, 2x 4ohms rated 30watts RMS.
they are all 100 or 150 watts...

Higher output is not an issue, that is what the gain can be used for. You adjust the output by lowering the gain.

 

[borisca]

thnaks again

I could not find this product in europe so I will go with this one :

Audio System CO 40.4 4-Kanal Verstärker

Viel Spaß für kleines Geld Die AUDIO SYSTEM CO SERIE bietet unverschämt guten Sound und das bei einem unschlagbaren Preis-Leistungsverhältnis. Grundsolide Technik in Kombination mit einem Ausstattungspaket, das keine Wünsche offen lässt...

www.car-audio.ch

it says : 4-channel amplifier digital with 4x 35 W RMS into 4 ohms or 4x 50 W RMS into 2 ohms

It should work, I have asked blaupunkt and the website about it, depending on the answer and the time I will take, I will keep the thread updated with picture

thanks

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edit 1 : response from blaupunkt

Hello,

the impedance must not fall below 4 ohms per channel if you connect the speakers directly to the device.
However, if you run the speakers through an external amplifier, this limitation of the unit does not matter, at this point the external amplifier must be able to work with the load.

If you have parallel connected speakers in the vehicle, they must be connected through an external power amplifier that is 2 ohm stable.
The wiring shown in the sketch is not applicable in this way, the connections do not match the car radio/amplifier as far as we understand.

Do you have four speakers in two doors or do you have four doors with one speaker each?
If you have four doors, it might make sense to connect the front doors directly to the radio and the rear doors as well as the speakers under the seats to the external amplifier.
Or connect the front and rear doors directly to the radio and the speakers under the seats to the external amplifier - in this case connect the amplifier to the subout output on the radio.
In none of these cases should speakers then be connected in parallel.

You write something about "under the seats", the speakers you purchased are a 2-way system, these reproduce the full spectrum, such speakers are less useful as bass speakers under a seat.

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He's suggesting to plug the 4 doors speakers directly to the radio and use the external amplifier for the remaining 2 speakers under the seat, which will reduce the number of channel I will need for the amplifier, meaning I could use a 2 channel amplifier at 4 ohms.
Can the radio and the amplifier work at the same time ?
Is this better than everything on the amplifier ?

thanks