Help! Harman Kardon 3485 produces no bass

[Mick Shrimpton]

I recently bought a shiny new Harman Kardon 3485 2-channel receiver and it looks pretty neat. I only wish it sounded as great as it looks.

The high and mid frequencies sound okay, but there is virtually no bass coming from my floorspeakers or subwoofer. The bass response is so poor, I suspect there's a problem with my receiver or my connections. I'm using a Sony SAWX700 active subwoofer and Infinity Reference 3-way floorspeakers. I've used three different methods to connect my speakers and subwoofer thus far, all to no avail.

1. Speaker 1 Terminals out to speakers and
Subwoofer Out Right to subwoofer line-level input via subwoofer cable
2. Speaker 1 Terminals out to speakers and
Y-splitter connecting Subwoofer Out R+L to subwoofer cable to the subwoofer line-level input
3. Speaker 1 Terminals out to subwoofer speaker input and
subwoofer speaker output to floorspeakers input

There is no audible difference in any of the three set-up configurations. Even if I turn the subwoofer volume all the way up and the crossover all the way down, I can barely hear it. My speakers and sub sounded terrific last week when they were connected to a 30-year old Sansui 7070 receiver, but with the Harman Kardon there is almost no low end at all.

Is there a set-up menu for the 3485 where I need to tell it that a subwoofer is connected? Or is there another method to connect the subwoofer?

 

[fmw]

Most likely it is a setup problem. Not all receivers send content out of the sub port for 2 channel listening without some setup issues. Some receivers want to use the sub port only within a surround mode or other mode in the digital processor. I'm unfamiliar with the receiver and can't give you specifics. To test things, however, just connect your main speakers to the sub and the sub to the main speaker terminals. That will get you all the bass there is to be had and will let you know if the receiver is a problem. I'd bet it is a setup issue. Modern A/V receivers can get pretty complicated.

 

[bandphan]

did you try the main pre outs to see if the sub worked?

 

[Mick Shrimpton]

did you try the main pre outs to see if the sub worked?

The receiver has left and right outputs labeled "Pre Out". Is it possible to connect my subwoofer to those outputs? Do I use a Y-splitter to connect my subwoofer cable to those outputs?

Thanks,
Mick

 

[Mick Shrimpton]

To test things, however, just connect your main speakers to the sub and the sub to the main speaker terminals. That will get you all the bass there is to be had and will let you know if the receiver is a problem.

I've already attempted the configuration you described, but my sub was still quiet as a church mouse.

 

[Mick Shrimpton]

Let me find an image of the 3485's rear panel so you can see all the outputs jacks.

 

[fmw]

I've already attempted the configuration you described, but my sub was still quiet as a church mouse.

Then there is no bass content in the recording or the sub is possibly adjusted improperly? Perhaps EQ? Preamps and amps can't address the frequency spectrum selectively without some sort of equalization.

 

[bandphan]

The receiver has left and right outputs labeled "Pre Out". Is it possible to connect my subwoofer to those outputs? Do I use a Y-splitter to connect my subwoofer cable to those outputs?

Thanks,
Mick

yes that should work.

 

[bandphan]

The receiver has left and right outputs labeled "Pre Out". Is it possible to connect my subwoofer to those outputs? Do I use a Y-splitter to connect my subwoofer cable to those outputs?

Thanks,
Mick

yes that will work, just try the left only to see if the sub is working

 

[Mick Shrimpton]

Then there is no bass content in the recording or the sub is possibly adjusted improperly? Perhaps EQ? Preamps and amps can't address the frequency spectrum selectively without some sort of equalization.

I've played bass-heavy recordings on LP and CD, but the subwoofer doesn't respond. I've adjusted the sub's crossover settings and increased the volume to max, and still didn't get anything. The receiver's bass knob is turned to max, yet there's still a lack of bass.

 

[Mick Shrimpton]

Here's an image of all the outputs on the back of the 3485:

http://www.harmankardon.com/images/product_large/HK3485B.jpg

 

[bandphan]

turn the sub down just in case it starts working, so you dont blow it

 

[mike c]

1) the pre out and subwoofer out should be outputting the same signal
2) never use a Y adapter from the L and R output into a single input on the subwoofer (you could have fried your input on the sub)
2a) use the R subwoofer output (either will work, but not both at the same time to one input)
3) the pre out and main in should have a jumper between them
4) if you've tried both speaker level and line level connections to the sub - it all points to the sub as the culprit
5) sony active sub = there's your problem right there seriously though, have you tried the sub with any other integrated amp or receiver?
6) if you don't have any other int. amp or receiver, turn down the volume of the sub until it is at the minimum, connect directly to a source, play source, wait for bass notes, turn back the volume just a little. if still no go ... it really is your sub that is busted.

 

[PENG]

I don't know what kind of Infinity 3 way floor speaker you have but if they are floor standing speakers you should be getting some bass.

Have you verified the phasing (polarities) of the right and left speakers. It is important that they are correct, otherwise the bass produced by the front speakers will cancel each other out. If the speakers are connected correctly, try reversing them on one speaker and see if it makes any difference. In rare cases, mistakes could have been made during the manufacturing process resulting in incorrect phasing even when you connect everthing up correctly according to the markings.

 

[brendy]

First,the HK has sub out jacks,the ones with the black ring.Those are the ones you should be using. I would check the sub. I had two of them and they both went bad about a year apart. A lot of others have reported the same thing. It was a good sub,just not reliable.

 

[bandphan]

First,the HK has sub out jacks,the ones with the black ring.Those are the ones you should be using. I would check the sub. I had two of them and they both went bad about a year apart. A lot of others have reported the same thing. It was a good sub,just not reliable.

he knows it ha sub outs(first page) the reason for using the preouts was to determine if the sub was dead