Increasing bass response in a combo? Suggestions?

[The Scarecrow]

Morning all.

Some of you may know I picked up another Rivera R100 212 combo this week on TM and thus far, it's been pretty awesome, though I find I am used to the low-end 'oomph' of my Knucklehead/2x12 cab setup. The R100 is an open back comob currently packing Celestion G12T 85's and I'm wondering if there's some suggestions to improve/tighten the low end somewhat?

I'm possibly too used to the sound of the Vintage 30/Heritage 30 setup I have in my 2x12 but I rember playing through some Celestion Hot 100's and note these seemed to have a chunkier low end. The 85's in the R100 are not bad speakers by any standard, but I'd like to get a bit more bottom end out of the combo and short of wanting to board the thing up and make it enclosed, I'm open to suggestion?

[hamo]

D, DF, F + Punch?



</lame video game joke>

[AmpShop]

I'd be totally keen to work on you with this one!

One of the first things to do would be to hear the amp in it's combo cab, and then here it through a closed-back 4x12 instead, to hear how much of the perceived lack of low-end is due to the combo cab. Once we've got a fair idea of that:

Speakers would be a good place to start. Followed by tubes - power and/or preamp. Even cabling - a fatter speaker cable may help.

Then there's the possibility of simple circuit mods such as larger-value coupling caps and/or filter caps - although without seeing/knowing the circuit, this may or may not be a possibility.

[Rog]

The Hot 100s certainly do have a lot of low end punch. I enjoy them.

[The Scarecrow]

D, DF, F + Punch?



</lame video game joke>

I was more a sonic boom man... eat that Zangief.

[The Scarecrow]

I'd be totally keen to work on you with this one!

One of the first things to do would be to hear the amp in it's combo cab, and then here it through a closed-back 4x12 instead, to hear how much of the perceived lack of low-end is due to the combo cab. Once we've got a fair idea of that:

Speakers would be a good place to start. Followed by tubes - power and/or preamp. Even cabling - a fatter speaker cable may help.

Then there's the possibility of simple circuit mods such as larger-value coupling caps and/or filter caps - although without seeing/knowing the circuit, this may or may not be a possibility.

Thanks Ryan, I was hoping you'd pick up on this topic given that I figured speakers would be at least partially contributing.

I might be best to come see you at the showroom sometime, think i have a day off next week during the week.

Here's the shot of the back, showing plenty of exposure.

[AmpShop]

Interesting cab design! Lots of open space on the back there.

[The Scarecrow]

Interesting cab design! Lots of open space on the back there.

Yeah, there was a reverb unit where the silver tape was, though that was taken out a while back from what I'm told.

[dayl]

Man, that looks like a whole lot of space, would step 1 not be closing the back? at least 3/4? and seeing how that sounds? ...

[ash]

Closing the back would probably result in overheating. You could increase the rear baffle area, but that probably isn't going to help enough before the heat issue kills it.

[RobRoyMcCoy]

Hey SC,

The easist thing to do is to unplug your combo from its speakers and instead plug it into your 2x12 and observe the differences. The next test could be to swap the speakers from the 2x12 into the combo. You may find after doing that the problem has gone away or not, but I suspect you will learn some stuff that will be helpful.

Rob

[RobRoyMcCoy]

Closing the back would probably result in overheating. You could increase the rear baffle area, but that probably isn't going to help enough before the heat issue kills it.

Excellent point.

[Bg]

yeah thats a wide open space should have got a Laney

[dayl]

Closing the back would probably result in overheating. You could increase the rear baffle area, but that probably isn't going to help enough before the heat issue kills it.

Excellent point.

Ooo save!

"I thought dayle made a great point so I followed his advice an now after a little use..my $3000 amp only crackles and pops'"

I didn't know that a 3/4 would no let enough heat out.

[Hot_Grits]

Do all that stuff with Ryan first. After that you could look at a new, larger, thicker back panel that covers maybe 2/3 of the space currently at the back. The key is to make sure there is still a decent amount of gap for airflow, especially near the tubes/chassis. Closing it off entirely would be suicidal for the amp.