How to prevent bass from going to main speakers

Guys, I think there is confusion here. I read Ted saying he has one amp that runs both the unpowered subs and the mains. Probably wired in parallel. He wants to high pass the mains. As already mentioned, he needs a simple series cap on the mains. If someone happens to know the impedance of the Maggie’s at around 100 Hz, you can tell him what caps to order from Parts Express or the nearest electronics dealer.

Did I get it right Ted?
 
not exactly. i have Adcom 5400 power amp 2 channel amp it has no sub out just left right out to magnipan 1.6 QR's. i have adcom gtp 502 preamp with line out that i run to sub. I want to prevent lowest bass frequencies going to magnapans where they will be reproduced with distortion.

it seems most stereo equipment will have a sub out which I don't have. if you have it does that mean sub frequencies go to the subwoofer and not to the mains?
 
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music soothes the savage beast
Joined 2004
Paid Member
isn't there a simple inline crossover that I could put between amp and mains that would prevent all signals below a certain frequency from going to mains. I have a lot a burned CD's from all over with vastly different recording levels. I'd rather set it once and forget it rather than adjust bass control with each track and throughout each track . Thanks!

I have used this simple passive crossover few times. Its cheap, and has quality parts. Allows your small speakers and two woofers being used with just one amp.
https://www.audioadvisor.com/mobile/prodinfo.asp?number=PACX1002

Btw, this thread is awfull to read. You are terrible at providing any useful information.
 
Since you said in post #24 that the preamp's line out goes to the sub (which must have its own internal amplifier),
there is still an option for a line level crossover for the Magnepans.

A small box with in/out RCA jacks, containing a series bipolar capacitor, would work.
If the Adcom is 51k input impedance, a series 33uF bipolar capacitor would make a first order
100Hz high pass crossover for the Magnepans.
 
diyAudio Moderator
Joined 2008
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51K in, 100 Hz 1st order highpass would be 0.052µF.
I see you've chosen the capacitive reactance to be half of the combined impedance. Clearly this is to make a -6dB response at the crossover frequency. It begs the question because many choose -4.5dB as the compromise. Some say the -6dB version sags too much.

So I made a comparison of all those with a second order Linkwitz-Riley at 100Hz, and your -6dB option appears viable by comparison if this is the needed crossover type.

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