HK 3480 & Sub-outs

[nightflier]

I have a Harman Kardon HK3480 receiver connected to a Music Hall turntable, a pair of Polk speakers and a DefTech sub. I originally connected the speakers via the sub using the speaker inputs, but the receiver also has a sub out, so I thought I would try that. The problem is that originally I could adjust the cross-over via the sub, but now I can't set this via the receiver.

How does the receiver establish the cross-over level? Is this adjustable? I noticed that other similar receivers (Denon DRA-395) also have a sub-out. Do they have the same problem?

[NickWH]

Which cross-over? High pass or low pass? It sounds like you are talking about the high pass crossover to the speakers. Unlike a HT receiver, the 2-channel ones usually have a fixed low-pass crossover (80 - 120Hz?) for the pre-amp outs. There is no crossover control for the main speakers. The speakers will get the full frequency range. This should not be a problem with most bookshelf speakers. Set the low-pass crossover on the sub to the -3db low frequency limit for your speakers. The transistion from your main speakers to the sub should be seamless.

[nightflier]

...The speakers will get the full frequency range. This should not be a problem with most bookshelf speakers. Set the low-pass crossover on the sub to the -3db low frequency limit for your speakers. The transistion from your main speakers to the sub should be seamless.

I'm not sure I follow. The HK receiver has no setting for a cross-over. On the HK surround sound (ARV) models, the cross-over can be set from 40-120Hz., so I was expecting this HK stereo receiver to have the same capability. But if I connect the sub to the RCA sub-outs on the receiver, there is nothing on the sub that I can adjust that has any effect. So I guess my question is, at what frequency does the receiver set the cross-over? If my speakers can go to ~45Hz., where does the sub take over?

[poneal]

email them your question. They will tell you what the crossover is.

[NickWH]

If my speakers can go to ~45Hz., where does the sub take over?

The low-pass frequency for the sub-outs on your receiver is definitely higher than this. Set the crossover on your sub to 45Hz, or as close as possible (50Hz is often the lowest setting).