Passive sub connection options?

[Alex2507]

I want to use a separate receiver to drive a passive sub. My idea was to use the sub out on an HK AVR 235 and run it into an HK AVR 20II using a Y connector, then to feed the passive sub with L & R speaker wire.

First I need to know that this will work.
Second, what should I plug the Y into (phono, VCR play, VCR record)?
Third, IIRC a passive sub without regular speakers to drive produces a full range of frequencies. How do I get around that?

Note: The mains are Primus 250's being driven by the HK AVR 235. I have a pair of small (4" driver) Primus satellites that I could plug into the sub if need be or would a resistor better way to go to fool the passive sub's crossover into thinking that there are speakers hooked up to it.

Fourth is the volume control factor. I imagine that I would turn the volume up to let's say 1/2 way on the AVR 20II and then calibrate the AVR 235 normally. Then when the volume is adjusted on the 235, the sub out signal would go up and down.

I actually tried this out yesterday but could not get the second receiver to drive the sub. I gave up on it 'till I got some more info. I am going to dig up a manual or two and do some reading but thought I would ask for help here also. TIA

Alex

Edit: I am doing this for a friend who I have just talked int buying my Primus 250's and Speakerman39's Primus C25 center. It's gonna take me a while to talk him into a powered sub. For right now I would like to keep his passive sub operating in the system without it crossing the mains over at 100hz. Thanks.

 

[TLS Guy]

I want to use a separate receiver to drive a passive sub. My idea was to use the sub out on an HK AVR 235 and run it into an HK AVR 20II using a Y connector, then to feed the passive sub with L & R speaker wire.

First I need to know that this will work.
Second, what should I plug the Y into (phono, VCR play, VCR record)?
Third, IIRC a passive sub without regular speakers to drive produces a full range of frequencies. How do I get around that?

Note: The mains are Primus 250's being driven by the HK AVR 235. I have a pair of small (4" driver) Primus satellites that I could plug into the sub if need be or would a resistor better way to go to fool the passive sub's crossover into thinking that there are speakers hooked up to it.

Fourth is the volume control factor. I imagine that I would turn the volume up to let's say 1/2 way on the AVR 20II and then calibrate the AVR 235 normally. Then when the volume is adjusted on the 235, the sub out signal would go up and down.

I actually tried this out yesterday but could not get the second receiver to drive the sub. I gave up on it 'till I got some more info. I am going to dig up a manual or two and do some reading but thought I would ask for help here also. TIA

Alex

Edit: I am doing this for a friend who I have just talked int buying my Primus 250's and Speakerman39's Primus C25 center. It's gonna take me a while to talk him into a powered sub. For right now I would like to keep his passive sub operating in the system without it crossing the mains over at 100hz. Thanks.

You where nearly OK. However I don't understand the Y-connector from the sub out. You will only be able to use one channel of the AVR 20 II. If there is only one set of terminals in the sub and you connected the left and right speaker outputs of the AVR II together, then the AVR II is history. You will have blown up both output stages.

 

[markw]

First off, unless the passive sub has two sets of speaker inputs, you can only use one channel of the AVR20. That "Y" connector will be useless.

As TLS hinted, the possible outcome of connecting the two channels to the one speaker might be a "phffffttt!" sound followed by silence. ...or there might not even be that "phffffttt!"

Of course, if you have two inputs on the sub, then your plan would work.

Second, you would feed the sub output of the AVR235 receiver to a high level ("aux" type) input on the AVR20. That would be something like a CD, VHS/Cable audio input, or something else that takes that level.

You would select that input and setting and the setting level would be a matter of trial and error. You now have, for all intents and purposes, a powered subwoofer.

The crossover and basic level would be adjusted via the menu options on the AVR 235. As with any powered sub, you'll have to find a happy medium between the sub's level control (the AVR 20) and the level adjustments on the AVR 235.

good luck.

 

[Alex2507]

Thanks for responding. There seems to be some confusion. I re-read my first post and think I see where I wasn't clear. The sub out from the AVR 235 is a single RCA Jack. (line level out put) I used an audio iterconnect to plug into that. The Y connector (1 female, 2 male) was used to plug into the L & R Audio In on the AVR 20II. All still RCA audio interconnects (line level).

Now the passive sub has 2 speaker level inputs ( L & R ) that I connected to the AVR 20II's L & R speaker connections.

I just got back in and looked up the sub on the computer and came up with this.

http://manuals.harman.com/INF/HOM/Owner's Manual/Sterling TS sat,sub system om.pdf

Page 3 shows a diagram of the connections on the sub. Let's skip right past critiqueing the sub's spec's. I'm pretty sure we're all aware that a big bowl of beans would produce deeper low frequency responce.

I'm gonna try to find the manual on the rec' now. Back in a few. Thanks.

 

[Alex2507]

Thanks for responding. There seems to be some confusion. I re-read my first post and think I see where I wasn't clear. The sub out from the AVR 235 is a single RCA Jack. (line level out put) I used an audio interconnect to plug into that. The Y connector (1 female, 2 male) was used to plug into the L & R Audio In on the AVR 20II. All still RCA audio interconnects (line level).

Now the passive sub has 2 speaker level inputs ( L & R ) that I connected to the AVR 20II's L & R speaker connections.

I just got back in and looked up the sub on the computer and came up with this.

http://manuals.harman.com/INF/HOM/Owner's Manual/Sterling TS sat,sub system om.pdf

Page 3 shows a diagram of the connections on the sub. Let's skip right past critiquing the sub's spec's. I'm pretty sure we're all aware that a big bowl of beans would produce deeper low frequency response.

I'm gonna try to find the manual on the rec' now. Back in a few. Thanks.

 

[markw]

Thanks for responding. There seems to be some confusion. I re-read my first post and think I see where I wasn't clear. The sub out from the AVR 235 is a single RCA Jack. (line level out put) I used an audio iterconnect to plug into that. The Y connector (1 female, 2 male) was used to plug into the L & R Audio In on the AVR 20II. All still RCA audio interconnects (line level).

Sounds good. The two male RCA's in that "Y" connector need to go to a high level input on the 20.

Connect the two speaker outputs on the 20 to the two speaker inputs on the sub.

The rest is a reprint from my last post.

Second, you would feed the sub output of the AVR235 receiver to a high level ("aux" type) input on the AVR20. That would be something like a CD, VHS/Cable audio input, or something else that takes that level.

You would select that input on the 20 and setting and the level would be a matter of trial and error. You now have, for all intents and purposes, a powered subwoofer.

The crossover and basic level would be adjusted via the menu options on the AVR 235. As with any powered sub, you'll have to find a happy medium between the sub's level control (the AVR 20) and the level adjustments on the AVR 235.

IOW, you should be good to go. Is this not the case?

 

[Alex2507]

IOW? I'm not on that level yet. What's it stand for?

I thought I was good to go. Seemed simple enough but it didn't work. I didn't want to wreck anything so I thought I would get some sleep and do some home work on it. The guy lives 45 miles away so I'm going to read through his manuals (he refuses to read them ) and make another stab at it.

I found the manual and on pg 9 item 18 starts talking about jumpers. I need to get my mind around that and will post any questions later.

http://manuals.harman.com/HK/HOM/Owner's Manual/AVR20II om.pdf

Thanks for confirming that I should be good to go.

 

[markw]

Good catch. Check page 8, item 18.

IOW? I'm not on that level yet. What's it stand for?

"In other words"

I found the manual and on pg 9 item 18 starts talking about jumpers. I need to get my mind around that and will post any questions later.

These jumpers connect the receiver's preamp stages to the it's internal power amps. If those jumpers are missing, you'll get nothing out of that unit.

By removing them, it's assumed that the "pre outs" will be fed to an external power amplifier 'cause the internal power amp is now useless! To use the internal power amps, you must replace the jumpers.

I guess he didn't tell you he removed these, did he? More proof that no good deed goes unpunished.

Replace these (or you can substitute a pair of basic audio interconnects) and then you should be good to go, hopefully.

Another possibility is that you can feed the "Y" connectors directly to the "main in" jacks, but I really don't recommend this. You won't have any control over the sub's volume except for what's in the AVR 35.

 

[Alex2507]

The jumpers are in, my problem lies elsewhere. Another possibility that occurred to me is that the sub out signal does not like being split. I could run the Sub Out without the Y into say AUX Left Audio Input. The AVR 20II has 2 Left and 2 Right speaker outs. I'll try using the 2 lefts to go to the sub next time I go down there.

Thanks for your efforts. I still need to read a mess of manuals in order to make sure I don't leave anything 1/2 a$$ed.

 

[markw]

did you isolate the problem to which receiver is causing it?

The jumpers are in, my problem lies elsewhere. Another possibility that occurred to me is that the sub out signal does not like being split. I could run the Sub Out without the Y into say AUX Left Audio Input. The AVR 20II has 2 Left and 2 Right speaker outs. I'll try using the 2 lefts to go to the sub next time I go down there.

Thanks for your efforts. I still need to read a mess of manuals in order to make sure I don't leave anything 1/2 a$$ed.

Trust me, splitting the sub signal is not the problem, assuming the "Y" connector isn't broken.

You should be able to play the FM in the AVR 20 (subwoofer amp?) and hear something from the subwoofer. It'll be muffled but at least you'll know that receiver is working. If you don't hear anything on FM, then there's a problem in the AVR20.

Assuming the 20 is working, that means something in the configuration of the AVR35 that's amiss.

 

[Alex2507]

I haven't been back down there yet. The day I set it up my first priority was to swap out the Infinity Primus HTIB that I had given to my friend a couple of years ago with a Primus 250 and C25 front speaker package that I sold to him. That included better speaker positioning and running new speaker wires through holes that he had drilled into the floors. Mission accomplished.

I took his sub out of the loop because it crosses at 100hz and now I have found that it only goes 4hz lower than the 250's. I don't trust that sub's anything. My friend, Eddie, lives an hour away so I really need a whole day to go there and play.

Thank you for the tip about the Y connector. It is fine. After all it is "Monster". Nothing but the best, right? I'll do my reading and get my info as best I can before taking a trip down there. There is a Yamaha R-700? receiver down there that I can use in case something is wrong with the HK AVR 20II.

When it's all said and done, I'll be sure to post the results. In the audio upgrade world, there is no substitution for success.

 

[Alex2507]

Success at Last!

The old H/K with the jumpers that was going to drive the passive sub has buttons for speakers 1 and speakers 2. Well if you don't get the right combination of buttons pressed no sound gets sent down the speaker wires I had plugged in. That's all it was. I didn't have the speakers activated.

I also want to add that the one remote operates both receivers I guess because they are both H/K so I covered the eye on the one used to power the sub so that the volume setting would not be affected.

 

[maximoiglesias]

Passive sub woofer connection

I had more or less the same case. My system is working perfectly powering a Pyle passive sub woofer with a Nec AUA-7300E reciever through a Y connector into the AUX input with the reciever set to MONO. It has worked very well. I can use my bass control (and treble controls) as well as loudness into my sub woofer.