Sub Problem

[Dante]

<font color='#000000'>I have a Wharfedale DX12 sub that I've been using for about two months. My old receiver did not have a LFE line out so I wired it through the &quot;sub optimal&quot; front channel connected wiring configuration. Given that the receiver was a 7 year old 50 watts per channel Pro-Logic receiver, it sounded pretty good. Actually, it sounded like it was going to knock a whole in my floor. That has all changed now.

I upgraded to a Denon 1804 and a Monster Cable THX connector. I initially set the SB volume level to max on the receiver so I could adjust it at the sub and set the crossover all the way up based on Crawling for Bass article's suggestion. All other speakers Evo 30's, 8's and centre are all set to &quot;Small.&quot; The problem is that when there is extended, deep bass or just a really deep drop the ports begin whistle. I've since made some adjustments but this involved turning the volume and crossover down which I don't really want to do. It makes me think that I should just go back to the &quot;less optimal&quot; setup I had before. I am hoping someone out there has a suggestion better than &quot;stuff a sock in one the ports&quot; which a friend of mine gave me.</font>

 

[gene]

<font color='#000000'>Dante;

Sounds like you are overdriving your sub and tasking it to product frequencies lower than it is tuned for.  I suggest to first lower the sub level via the receiver to say -6dB or so and then readjusting your sub volume and phase.  You should try not to use the subs crossover since your receiver already has one built in.  Simply defeat the sub crossover or set it to the highest setting.  Also, adjust the crossover point in your receiver to give you the best blend with your mains.  Usually between 60-100Hz works well depending on the bass capability of your speakers and if you have them set to large or small accordingly.

You may also wish to experiment with sub placement to achieve better room gain so it doesn't have to work so hard to put out the SPL levels you are demanding.

[edited: spelling]</font>

 

[Dante]

<font color='#000000'>Thanks for the quick response! I will try your suggestions out this afternoon. Just a few comments and hopefully one last question.

The sub is rated down to 25Hz which isn't phenomenal but for price I gave it is exceptional. As I said earlier, there were no problems with the first setup I tried.  Anyway, the Denon 1804 has a crossover at 80, 100, 120 I think and maybe 160. Regardless, I can't cut at any point lower than 80Hz through my receiver. It seems to me that I would want to use the sub's continous variable crossover with a range from 60 to 170Hz. This would give me more flexibility and allow my fronts take up some of the demand. However, I don't know if I can turn off the receiver's crossover. Would it make sense not to use the receiver's crossover if I can successfully utilize only the crossover on the sub?</font>