New receiver, or add a amplifier?

[Skeeter]

+1

get a proper sub, cross your speakers over at 70 or 80hz and bob's your uncle. should go plenty loud.

dotVIBE, please remember this comment.  I want to start another thread with my own Onkyo problems.  Very similar setup to xrapidx!

[xrapidx]

Just out of interest, have you adjusted the volume under the source setup and intellivolume section?
Mines sitting at +12 and it gives me a much better sound without having to crank up the volumes. To give you an indication, my 705 receiver driving my RTi8's at volume 55 (on the setting where max is 99) is disco loud

Nope - normal settings - isn't that just the same as turning up the volume though? I don't like going to high incase the source, such as DSTV plays a loud advert that'll kill the speaker. (not even sure if thats possible)

when you say source, do you mean the mede8er? 'cause I find that with most sources, but ESPECIALLY my media box, keeping the volume at 0 and using the AVP to control the volume gives significantly better sound.

IIRC :: In the receiver menu's somewhere you can set the volume per source

[dotVIBE]

dotVIBE, please remember this comment.  I want to start another thread with my own Onkyo problems.  Very similar setup to xrapidx!

any time dude, there are lots of us here who can help with that kind of stuff.

[xrapidx]

Regarding sub - its a difficult one, because the higher end BIG subs are seriously overpriced in SA.

Maybe two small ones? I know goneten recommended two Jamo SUB300 - so maybe thats an option as opposed to a large 15"
 

[Stefan]

DIY?

[xrapidx]

Is it possible to match the quality of a commercial one in terms of functionality and looks wise?

I had an offer on this forum awhile back from someone to make one - can't find the PM now.

[Stefan]

Well, if you go for something like JimGore suggested in another thread, the JBL driver does look like something that belongs in the back of a VW. But, there's always a solution, like mounting in facing downwards. The rest of the enclosure is up to you to decide or building skills.

[Hennie]

..........Maybe two small ones? I know goneten recommended two Jamo SUB300 - so maybe thats an option as opposed to a large 15"

Generally speaking two smaller subs in different positions in the room will give you a smoother response. Three small subs are even better.

[xrapidx]

Generally speaking two smaller subs in different positions in the room will give you a smoother response. Three small subs are even better.

And they're reasonably priced I don't think my room is big enough for three though... 5.7m x 4.2, 3 piece lounge suite, fairly large speakers, AV setup against the side wall.

Also, maybe a noob question, but will the woofer's on the RTI A9's still be used at all?

[Hennie]

Well with three in parallel your mains have a significant output capability. In the interest of bass smoothness overlapping the mains with the subs would be very useful. (More bass sources tend to counteract room resonances and give better bass smoothness. The more the better.) In practice with AVR bass management it is not always possible or easy to do. There's also an increased risk of overdriving the mains at extreme LF.

If you use the AVR's bass management, then the woofers of your mains would be used above the crossover frequency and the subs below that. This is the conventional option.

Another option would be possible if you could set the AVR to the following:

Mains as large
Surrounds as small
No subwoofer
Drive the subwoofers from the speaker outputs to the mains IF the subs have suitable high level inputs. Check that they are electrically compatible. (A few amps give bridged outputs and most sub high level inputs can't handle that)
Stuff the ports of the mains to reduce the risk of LF overload.
Adjust the level of the subs to just subtly fill in the mains
Experiment with the position of the subs until you get the smoothest response. Space the subs widely apart. Start with one in the corner and another against the side wall halfway between the corners. Adjust sub level and phase and bandwidth (if provided). Start with the sub's built-in crossover at maximum setting for maximum overlap.

This would give you the most bass sources and would generally be smoother than the conventional option with bass management. It also requires a fair amount of twiddling to get right. The conventional option with bass management would be louder though. Perhaps experiment and see what you like best.

[Daniel Weston]

Nope - normal settings - isn't that just the same as turning up the volume though? I don't like going to high incase the source, such as DSTV plays a loud advert that'll kill the speaker. (not even sure if thats possible)

IIRC :: In the receiver menu's somewhere you can set the volume per source

Give it a try, as you adjust that source setting up to +12, you will notice a major difference in the sound volume. You won't break anything provided you start with the receivers volume down low. To give you an idea, we watch tv day in day out at volume 20 to give you an indication of what current volume setting we use that is acceptable in terms of being able to hear properly.

[dotVIBE]

And they're reasonably priced I don't think my room is big enough for three though... 5.7m x 4.2, 3 piece lounge suite, fairly large speakers, AV setup against the side wall.

Also, maybe a noob question, but will the woofer's on the RTI A9's still be used at all?

Sure the woofers will be used, they will play everything from 80hz up to where the tweeter frequency crosses over. At like 3000Hz or whatever.

The main benefit of having 2 or three smaller woofers is in neutralizing room nodes. I you can equalize it properly you can get it so that there a no nulls or peaks in the room. One larger subwoofer might actually give you more low frequency extension and dB, but you won't be able to equalize the room nearly as well.

[Vaughan]

If you want the greatest headroom, lowest distortion and highest dynamic range then use bass management with multiple subwoofers. Due to the LF extension of the RTI-A9's, I would choose a slightly lower x-over option between 60-70 Hz to facilitate a smoother roll-off between speaker and subwoofer. The more capable the mains down low, the smoother the splice tends to be down low because the roll-off slope compliments the lower bass extension of the mains. Remember, once bass management is activated the mains will still produce bass to well below the crossover point but at a lower level (12 dB's/octave).

[PAPPA3]

Just joining here.  My concern with smaller subs is that they don't play down as low as the bigger ones.  So even if there's more bass and it's smoother, you still miss the very bottom end.  Re prices, Ive always seen good items on the forum advertised at better prices than buying them new.  My preference would be to buy a good large sub from the forum instead of buying smaller subs new.  Re resonance, rooms also need bass treatment with traps and the like.

[Vaughan]

You'll still miss out on the bottom end with a bigger subwoofer unless you have a properly designed IB. So no matter what subwoofer you have short of an IB or a Thigpen Rotary sub, you'll be stuck with a compromised solution. Multiple smaller subwoofers are simply more cost effective in the long run (IMO) because they generally offer better bass uniformity when set up correctly and many dual subwoofers options can outgun a bigger sub within their limits. So dynamically you have a more potent solution for the same money within 85-90% of the bass range.

Concerning resonances, the bigger sub with a deeper response can also energize room modes easier which may result in a worse response in your room. So again, do you buy a bigger sub to get that extra 5-10 Hz extension, or better linearity higher up with a smoother bass response ? As for buying used vs new, well, if you buy new then you have a warranty. If you buy used then anything goes, whether it was a better deal or not.