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Reference 4-1 issues / SP2226 schematic

 
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zxcasd
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Joined: 23 Feb 2006
Posts: 2

PostPosted: Thu Feb 23, 2006 6:52 pm    Post subject: Reference 4-1 issues / SP2226 schematic Reply with quote

Could someone provide a schematic for the SP2226 crossover from a Ref 4-1? I have a pair of these Ref 4s with indeterminate problems that seem to be identical between the two units - particularly, very very low volume from the tweeters - not distorted, just very low. The other drivers seem to be doing well.

Also, concerning internal construction of these, is there another crossover for the uni-Q driver? I've removed the crossovers, which only have the single green (high) and brown (low) wire pairs going from them, but I see more colors up above on the Uni-Q driver, so I'm wondering where they tie in together. Thought I'd check here before I totally disassemble the box. Smile

thanks,

Tom
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ColinR
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Joined: 31 Jul 2004
Posts: 1175
Location: Staffordshire

PostPosted: Sat Feb 25, 2006 12:44 am    Post subject: Reply with quote

No idea about SP2226, but the crossover treble section will be something like + two capacitors to make a value, inductor+ to -, + a Zobel + (resistor in parallel with a capacitor), inductor + to -, drive unit connected out of phase.

If the fault is intermittent, you have a loose connector on the pcb.

If it's constant you've fried the driver.
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zxcasd
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Joined: 23 Feb 2006
Posts: 2

PostPosted: Sat Feb 25, 2006 12:53 am    Post subject: Reply with quote

Thanks, Colin.

I'm waiting for an inductance meter to arrive - the rest of the parts on the crossover look good, so yes, it sounds like it's probably the drivers. Fortunately, I have a pair of Reference 1s arriving today in (presumably) mint condition. If they work, I believe the Uni-Q driver is the same between that and the Ref4, so I'll try swapping and see how it works. I won't mind cannibalizing a pair of Ref1s to make good a pair of Ref4s, especially when the 1s only cost me $350 for the pair. Smile
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