Beginner needs help not blowing up audio system

[phototr0pe]

Hi guys,

I was just hoping to get some expert opinions before I blow anything up. I have a 120 watt "bookshelf" amp (Sony CMT-HP7) with what I guess amounts to a single stereo output--i.e. it has two left and right speaker wire outputs to two separate speakers. I also recently came into possession of a 120 watt Yamaha subwoofer (sw p3600) which I think was originally part of a set--it only has a +/- mono input, and no outputs or other controls.

Is there any way to safely add the subwoofer to the existing two speakrs? Do I need another amp for the subwoofer to isolate the bass signal, and if so, what kind would you recommend? I read about summing circuits, and I'm pretty handy with soldering things and building circuits on breadboards, so I could build one of those, but does my amp even have enough juice for this thing? What happens if my amp doesn't--are the speakers just quiet?

Thanks in advance for your help.

 

[croseiv]

Hi guys,

I was just hoping to get some expert opinions before I blow anything up. I have a 120 watt "bookshelf" amp (Sony CMT-HP7) with what I guess amounts to a single stereo output--i.e. it has two left and right speaker wire outputs to two separate speakers. I also recently came into possession of a 120 watt Yamaha subwoofer (sw p3600) which I think was originally part of a set--it only has a +/- mono input, and no outputs or other controls.

Is there any way to safely add the subwoofer to the existing two speakrs? Do I need another amp for the subwoofer to isolate the bass signal, and if so, what kind would you recommend? I read about summing circuits, and I'm pretty handy with soldering things and building circuits on breadboards, so I could build one of those, but does my amp even have enough juice for this thing? What happens if my amp doesn't--are the speakers just quiet?

Thanks in advance for your help.

Just connect the sub via the speaker level connections (if it has them) to your speaker level connections on the receiver. Your amp may struggle a little though.

 

[croseiv]

Here is a manual for a PSW125 that explains how to run speaker level connections.

 

[Adam]

Just connect the sub via the speaker level connections (if it has them) to your speaker level connections on the receiver. Your amp may struggle a little though.

The issue is that the passive sub has one set of speaker-level inputs (mono), and the amp (that is part of a mini-system) only has one pair of speaker-level outputs for the two speakers that came with the system.

I think the question is - is it safe to connect the sub to the speaker-level outputs in parallel with the other speakers? Also, is the impedance of the sub too low for the amp?

My personal opinion is that it won't be worth trying to connect that sub to that mini-system. Just my two cents.

 

[croseiv]

Well if there aren't any "speaker level in" connections then it probably is a no go...

 

[Adam]

Well if there aren't any speaker level connections then it probably is a no go...

There is one set of speaker-level connections on the sub. It is a passive sub that was part of the Yamaha YHT-370 home theater system. It would have originally been powered by the receiver that was part of that system.

EDIT: Oops. I see that you modified your post. Yeah, it would be great if it was a powered sub with speaker-level connections, but unfortunately it's not.

 

[phototr0pe]

Thanks, guys. I guess I'll just hold on to the subwoofer until I can get something that will work for it (got it used for $20 so it's not like it's a huge lost) ...maybe it's an excuse to upgrade my audio equipment from a dinky little bookshelf unit to something better!

 

[adwilk]

Thanks, guys. I guess I'll just hold on to the subwoofer until I can get something that will work for it (got it used for $20 so it's not like it's a huge lost) ...maybe it's an excuse to upgrade my audio equipment from a dinky little bookshelf unit to something better!

If you had some cash lying around you could order one of these...