Hi everybody...
Someone has t&s parameters of the drivers used in this speakers???
Bose don't give any information...
And... for tweak this speaker i can also modify the crossover network... i posted the schematic of the original crossover...
note that the fuse in the schematic seems to be a lamp used as a fuse...
SUGGESTIONS FOR A MOD/TWEAK OF THE CROSSOVER???
Someone has t&s parameters of the drivers used in this speakers???
Bose don't give any information...
And... for tweak this speaker i can also modify the crossover network... i posted the schematic of the original crossover...
note that the fuse in the schematic seems to be a lamp used as a fuse...
SUGGESTIONS FOR A MOD/TWEAK OF THE CROSSOVER???
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Flavio88 said:
Now if that crossover doesn't justify the phrase "better sound through engineering", I don't know what does.
Without measuring the drivers, a modified crossover would be pretty difficult to suggest.
As a guess, small inductor in series with the woofer might make the upper midrange cleaner, or it might just muck things up. You could replace the bulb with a series resistor and a fuse, but the point where you have a large enough fuse to avoid a nuisance tripping issue is where you will blow those little tweeters.
About 18 years ago, a friend had a pair of these on either end of a long dresser pulled out into the room a bit, with his stereo system and TV between. The room was very reflective, and I remember that they sounded very nice with U2 and the Smiths, the Cure, Morrisey, etc... Some of those recordings sound pretty harsh on my current system, so the euphonic muddying character of the direct-reflect may have been a benefit...
The lamp actually is a little more sophisticated than just a resistor and fuse combination - at reasonable levels the resistance of the bulb is quite low, as power is increased the filament starts to heat up reducing power delivered to the tweeters - can you spell compressor?
Incandescent lamps have a positive resistive coefficient - as they heat up the resistance increases. This particular lamp was chosen very carefully to complement the power handling capability of those tweeters.
Unfortunately I no longer remember the correct values for those caps..
An escaped boso
Incandescent lamps have a positive resistive coefficient - as they heat up the resistance increases. This particular lamp was chosen very carefully to complement the power handling capability of those tweeters.
Unfortunately I no longer remember the correct values for those caps..
An escaped boso
Yes, but do you know the correct lamp cold resistance value to set the tweeter level? You'll find very few commonly available dmm that do good low ohm measurements. I think an Lpad might be a better choice... Probably is not too critical in any event. Fuses incidentally are not too linear either, if you know you are not going to abuse the speaker I would get rid of it.
Without being too blatant about it I obviously know about the positive temperature coefficient of that specific light bulb..
Without being too blatant about it I obviously know about the positive temperature coefficient of that specific light bulb..
kevinkr said:Yes, but do you know the correct lamp cold resistance value to set the tweeter level?
Without being too blatant about...
The temp coefficient info was for the original poster and general information, not to "educate" you.
If one knows the original bulb voltage and wattage, one can derive a starting value for resistance experimentation from that information. The resistance should be relatively easy to measure - but the Lpad is not a bad idea. The jist of my mentioning the fuse and nuisance tripping was to (poorly) hint at why the bulb is there and that it might not be worth replacing. Those tweeters honestly can't handle much power unprotected.
That was my advice to him as well, seems we are pretty much of the same mind on this issue.
I've seen one or more than a few AM-X bass modules where the terminal cup in the rear of the bass cabinet had melted due to the heat from multiple bulbs. The bulbs themselves in some instances had partially melted as well. Well toasted at parties...
I've seen one or more than a few AM-X bass modules where the terminal cup in the rear of the bass cabinet had melted due to the heat from multiple bulbs. The bulbs themselves in some instances had partially melted as well. Well toasted at parties...
So, is this schematic posted before correct or not?
I know that inside this speakers I found two caps: 4,5mfd, and 22mfd "Nichicon" 50 v bipolar and green ones-both.
The bigger "tweeter or mid range driver??" was silent like as dead, when playing music, but was 100% O.K. as I measured it outside the crossover????
I wonder what's the purpose cos even a "dB" doesn't come from it???
or it is fixed just for art looking?
I know that inside this speakers I found two caps: 4,5mfd, and 22mfd "Nichicon" 50 v bipolar and green ones-both.
The bigger "tweeter or mid range driver??" was silent like as dead, when playing music, but was 100% O.K. as I measured it outside the crossover????
I wonder what's the purpose cos even a "dB" doesn't come from it???
or it is fixed just for art looking?
Flavio88 said:bigger rear tweeter???? 22uF???? 4.5uF???? why those differeces?
rear and front tweeters are two of a kind...
I think you have'nt a 301 V...
Maybe a IV series or a different speaker...
please check...
Was long time ago, and that crashed speakers was not mine, was repaired by other peoples, re wounded.....etc!
It was very unusual when I saw that bigger cap (I am not sure it was 22mfd or 15mfd) was connected in parallel to the one of that tweeters which was re wounded (by hand).
I never seen that kind of filter crossover such a big cap direct bypassing the tweeter or mid range, cos other cap in whole series circuit( the lamp, than 4.5mfd cap than one tweeter than other tweeter which is bypassed by 22 or 15 mfd cap) It is very uncommon for me(perhaps that tweeter has a very very low impedance lower than 2 ohm) the lower the impedance the bigger capacity is needed on a filter cap series or parallel(coupling or decoupling cap)
I am 100 % sure that other cap was 4.5mfd 50V Nichicon bipolar and green color.
I don't remember what series was but for sure was Bose 301.
Now I think that speakers must be somewhere i n garbage, because that guy used this small speakers in a pub for a disco parties
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