Altec Lansing 641 - Page 7

I want to ask Scoob something
about Bss84 If in the two big capasitors I have 24V and 22v that means that the stabilizer circuit (bss84 7805 etc) is working ok, and the problem is elsewhere?
I have sound from the satellites, and sometimes from only the one woofer. ( The woofer is ok )
Thanks
Leonidas

quote

Dammit i actually had my sub going for a few weeks but then it stuffed up again so i opened it up to check out the components again. While doing this i must have bumped off the little part at r30 (next to the big capacitor on the sub board). I don't know what number it had on the top. Is this part a resistor?? If anyone knows what this part does or has their sub open so they can tell me the part number i would be very thankful.
I figured out what part was stuffed (and caused me to open my sub again), it was the Q5 rectifier as scoob has suggested. Thanks to anyone who can help
waz

R30 is a 100K ohm 5% resistor, 0603 SMT package.

hello
i want to have a account of dark and light .but i donot know how to get it ,someone tell me to register on [link name=][/link]www.darkandlight.us but i do not know when it will begin to register . help me if you know it .

Brent,
Thanks for all the valueable help you have contributed to this thread and owners of the 641 system.

I have a question to pose to this thread. My 641 system had suffered a burn out after moving it to the Uk. I had tried to use it with a voltage converter for the ac power here at 220v. Instead of going through all the hassle of trying to fix it (there were no obvious burned out components on either the power supply or amp boards), I decided to power it with an external amplifier. I just found and purchased a second hand 5.1 channel subwoofer amp that was removed from a home cinema subwoofer cabinet and I will attempt to replace the electronics in the 641 with this amplifier.

My problem is:
I need to find out what the specs are on the 641 speakers as I don't want to risk blowing them out if this sub amp is either under or overpowered for them.

I will need to know the power handling in watts (peak and rms) as well as the impedance for the satellites and both of the woofers in the sub cabinet. I know the total system power is 400 watts (200 watts RMS), but I need to figure out what the individual figures are for the satellites and subwoofer (including impedance Ω. If not this, then the output of both the satellites and subwoofer amplifier boards.

Any help or advice would be much appreciated.

Thanks,


This message was edited by c_martini on Sep 15 2006.

quote Scoob

Check the 641 webpage in my previous post. I just added a quick connect guide, and specifications for you, and anyone else who wishes to have this information too.

As far as using an external amp, with respect to specifications, it is better to "over power" a speaker than to "under power" a speaker. It is better to use an amp that is as close to the specifications as possible, without being significantly higher or lower than the rated specifications.

A higher power amp will drive the speaker harder at high volume, resulting in damage from audio signal. A lower power amp can result in high volume damage, with distortion, causing the amp to clip (momentary pulses of DC voltage). If the amp clips enough it will lock to the DC supply, resulting in damage, and burning out the speaker, literally.

You would have to turn the volume up on a lower powered amp to get as good of sound as a higher powered amp. With a higher powered amp, you wouldn't have to turn it up as much to get good sound quality.

Hope this is helps.

Many thanks, exactly what I was after. I had that spec sheet at one time, but it was lost long ago... I have taken your advice on board as well. I do not know all the specs of the replacement amplifier but I suspect its very close if not slightly higher powered than the 641's amps, so I should be ok. It even has an extra channel for the center dialog, so I will probably either try to locate another satellite or use a spare speaker that I have laying around.

Thanks again.

Hi,

I recently purchased a 641 system that had never been removed from it's factory box. Since it's unused everything works fine now, but I was wondering if anyone with experience diagnosing the failed sub power supply problem had any tips to prolong the longevity of such a virgin system.

From what I read, it seems like it might be a good idea to remove power from the sub when not in use (like, via a switched power bar and not the remote's power switch). Any other tips?

Thanks in advance!

I'm just wanted to thank you to Scoob for your interest and experience on this system trying to help us to repair our equipment.
Unfurtunally my system still broken "woofer sound very low" and every tip was applied on it with out any good results. All voltages are present according to the diagrams, but since to be like it's something else.
If any one has more recommendation I will appreciate your help. Otherwise I will able to buy your broken system for debugging purposes.

Please contact me at:

gidilo@bellsouth.net

I was wondering if it would be possible to get a copy of those direction for fixing the 641 subwoofer. The geocities link doesn't seem to be working anymore.