[baz_4]

Originally Posted by illingworth22

I reckon the reason why the Amps keep blowing is due to the following
http://www.teamrocs.com/technical/pa...ngspeakers.htm or http://www.bcae1.com/spkrmlti.htm

See connecting Speakers in Parallel. All the front speakers & the Subs are connected in Parallel.... If you have either added yourself or had the tweeter fitted as standard you now have three x 4 Ohm speakers connected in parallel. This equals a load on the amp of less than 2 Ohms (1.3333Ohms to be exact). This wil most definatly cause the Amp to burn out!
I got home last night and the wife came home a few mins after me. She said she could smell burning by the car. I went outside and thought SHITE. I could smell something similar to (remember when you used to solder speaker wires and the plastic would melt!) warm or burning plastic! My nose went all round the car and I could not tell where it was coming from, but there was a strange smell. I park my car in an enclosed car-port under the house so the smell lingered for a while but as I have no doors as such the smell went after a while. I am now driving round with the Radio whispering at me.! I will have to re wire the system some how.... Thinking I will have to disconnect the Subs from the Front curcuit and re connect them in parallel to the rear speakers?

One more option is to Buy the THA 1250 and Connect the Subs Directly to that

Any Ideas?????

This post is confusing/concerning me!!
Would it be wrong to just add an amplifier to the standard set up?
If i were to add the THA 475 or THA 275 without touching the underseat subs etc?

[sniffer]

Originally Posted by illingworth22

I reckon the reason why the Amps keep blowing is due to the following
http://www.teamrocs.com/technical/pa...ngspeakers.htm or http://www.bcae1.com/spkrmlti.htm

See connecting Speakers in Parallel. All the front speakers & the Subs are connected in Parallel.... If you have either added yourself or had the tweeter fitted as standard you now have three x 4 Ohm speakers connected in parallel. This equals a load on the amp of less than 2 Ohms (1.3333Ohms to be exact). This wil most definatly cause the Amp to burn out!
I got home last night and the wife came home a few mins after me. She said she could smell burning by the car. I went outside and thought SHITE. I could smell something similar to (remember when you used to solder speaker wires and the plastic would melt!) warm or burning plastic! My nose went all round the car and I could not tell where it was coming from, but there was a strange smell. I park my car in an enclosed car-port under the house so the smell lingered for a while but as I have no doors as such the smell went after a while. I am now driving round with the Radio whispering at me.! I will have to re wire the system some how.... Thinking I will have to disconnect the Subs from the Front curcuit and re connect them in parallel to the rear speakers?

One more option is to Buy the THA 1250 and Connect the Subs Directly to that

Any Ideas?????

Hi, I think you are bang on the money. I wouldn't use it in this configuration.

Don't forget. . .NO FACTORY CARS WOULD HAVE HAD THE TWEETER INSTALLED WITH THE SUB IN PARALLEL.

The cars which got tweeters were logic 7 and hi-fi. . .In both these configurations, the subs are driven by seperate channels from the respective systems amp.

Therefore, by adding tweeters to a wiring configuration which already has 2 x 4 ohm speakers in parallel, you are effectively making that channels impedence 1.333 Ohms.

This would blow the amp which should probably be operating at a minimum of 2 ohms on any channel. Not entirely sure on the specs of the Blaupunkt amp but I doubt it will run for long with such a low resistance on a channel.

[baz_4]

Sniffer, am I still affected even though i have an E92 with factory fit tweeters?
I thought they would also be wired in parallell?

[sniffer]

Originally Posted by baz_4

Sniffer, am I still affected even though i have an E92 with factory fit tweeters?
I thought they would also be wired in parallell?

If your car has factory fit tweeters, it does not have the BMW standard audio.

Just to clarify, the tweeters are the little speakers in the triangular panel behind the mirror. If you have these from factory, you have upgraded audio; either have the BMW Hi-Fi loudspeaker system, or Logic7.

To check, you should have two speaker grilles in each rear interior panel as opposed to the single grille on the BMW standard audio.

In this case, each sub is driven by a seperate channel on the BMW amp. Therefore, only the mid and tweeter are in parallel on each front channel, meaning an impedence of 2 Ohm.

[illingworth22]

Like I said I added the Tweeter (Traingle Unit on top part of door) speakers. I notice If I put the volume up high I get the burning smell. I don't know if it is the Amp that is smelling or if any of the wires in the Blaupunkt loom are melting The amp is deffo drawing less than its 2 Ohm limit !
Anyway when summer comes I will take the Subs out of the connection and will try to get a separate amp to drive them. I am not sure where I will get the feed for the second (Sub) amp as I can't remenber if the Blaupunkt has pre outs. I don't have the 5 channel 555, I have the 4 channel 475 amp.

[sniffer]

Originally Posted by illingworth22

Like I said I added the Tweeter (Traingle Unit on top part of door) speakers. I notice If I put the volume up high I get the burning smell. I don't know if it is the Amp that is smelling or if any of the wires in the Blaupunkt loom are melting The amp is deffo drawing less than its 2 Ohm limit !
Anyway when summer comes I will take the Subs out of the connection and will try to get a separate amp to drive them. I am not sure where I will get the feed for the second (Sub) amp as I can't remenber if the Blaupunkt has pre outs. I don't have the 5 channel 555, I have the 4 channel 475 amp.

If I were you I would probably whip off the door panel and put the mid and the tweeter in series using a bit of wire and a couple of spade terminals to insert into the connectors. This would change the resistance so that you had 8 ohms (tweeter and mid in series) in parallel with 4 ohms (sub). This would then give an impedence of 2.6666 ohms which would stop the amp frying and resolve the issue.

Only think I am not sure of is whether the inline capacitor would work for the high pass on the tweeter.

Or you could always whip the door panel off and just disconnect the tweeter lead while you plan what you are gonna do.

[illingworth22]

Originally Posted by sniffer

If I were you I would probably whip off the door panel and put the mid and the tweeter in series using a bit of wire and a couple of spade terminals to insert into the connectors. This would change the resistance so that you had 8 ohms (tweeter and mid in series) in parallel with 4 ohms (sub). This would then give an impedence of 2.6666 ohms which would stop the amp frying and resolve the issue.

Only think I am not sure of is whether the inline capacitor would work for the high pass on the tweeter.

Or you could always whip the door panel off and just disconnect the tweeter lead while you plan what you are gonna do.

So wire up as in B instead of A? Where the little box is a speaker!



This means I have to take the fecking door panels off again

[sniffer]

Originally Posted by illingworth22

So wire up as in B instead of A? Where the little box is a speaker!



This means I have to take the fecking door panels off again

Yeah, your diagram is what I am saying. The door panels are not too hard to get off though really.

If you get the right size spade terminals male and female, you will not need to cut or modify any of the wiring.

I am a little concerned about the in-line capacitor though and what affect it would have . . . as I understand it, the capacitor filters out low frequencies, so perhaps the tweeter MUST be wired in parallel.

Anyone got a view on this? Would it work?

[Lotus99]

Here's a good link to check out: http://www.teamrocs.com/technical/pa...ngspeakers.htm

[Blaa]

Thanks for a great write up.. Lots of good tips for when I'm installing the 555 in my 318d M-Sport I'll be picking up in Germany the 29th..