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A popular bass amp in the old forum. Saw them mentioned in another thread and figured I'd start a thread for general discussion.

Cool? Cool. So my first question:

I play through an early 00's SS Fender Bassman head. It has served me well but it's got a baked in 'modern' scoop that I've grown weary of. I've got an 800RB but when I've used it at practice it sounds thinner than I'd like. I've heard that by comparison the 400RB has more low end. I don't think I'd miss the wattage (we use drum machine, although guitarist is subject to volume creep).

Also I'm a lazy bastard and like to record direct. I'd probably be ok with the 1/4" out to a DI vs. XLR.

Perhaps a 400RB would be more to my liking?

Please discuss.

Is the boost section engaged?

On my 400rb I’ve always had the boost engaged (you need a foot switch to turn it off) and the dial at noon. I’ve tried it with the boost knob all the way counter clockwise and it never sounded as good.

Can’t speak for the 800 but that’s the first thing I’d check.

ErikG wrote: Sun Jun 25, 2023 4:49 pm A popular bass amp in the old forum. Saw them mentioned in another thread and figured I'd start a thread for general discussion.

Cool? Cool. So my first question:

I play through an early 00's SS Fender Bassman head. It has served me well but it's got a baked in 'modern' scoop that I've grown weary of. I've got an 800RB but when I've used it at practice it sounds thinner than I'd like. I've heard that by comparison the 400RB has more low end. I don't think I'd miss the wattage (we use drum machine, although guitarist is subject to volume creep).

Also I'm a lazy bastard and like to record direct. I'd probably be ok with the 1/4" out to a DI vs. XLR.

Perhaps a 400RB would be more to my liking?

Please discuss.

What cab are you running into? Some Ampeg 8x10s have upper and lower sections with individual inputs that you can run stereo and you can then run the 800 to it's full effect using both 100w and 300w amp sections and play with the crossover to your liking.

I do still find the 400rb has a lower reach on the low end frequencies that either isn't there on the 800 or is masked by other frequencies so you may have to play with the EQ in a way you're not 'expecting', but as FM Ben Adrian said in another thread it can really depend on the cabs.

That said I wouldn't think to ever describe the 800 as 'thin', so maybe you have something else going on.

I've got an audio analyzer at work, if I think of it I'll check the DI on both at flat.

I love the geekiness of the bi-amp setup of the 800 and the sheer power - but for all practical reasons, I think I've only missed the wattage on 1 or 2 occasions where a two guitar band and drummer was really slamming. The 400rb through an appropriate speaker is fucking loud. And it fits in a backpack.

The quilter offerings by all practical reasons are probably just as good/better? The Seymour Duncan PowerStage similar, and other 'small block' heads, but I've had my first 400rB for 20 years without a single problem. It survived the abuse of learning about amps, touring in a hardcore band, and using it at least once a week with synthesizer for 4 of those years,

They look great!

400rb for 250$ at the shop I used to frequent back in east Texas. He won't ship it though.

I use both and they are pretty damn similar. The 400RB has a bit more grip but the 800RB would definitely not be described as a "thin" amp by any stretch, I'd get yours checked out. As far as the boost goes I dial it out on both, I never got along with it.

There are some slight component value differences between the 400RB and 800RB preamp circuits that could account for the difference in low-end that people perceive. Especially around the boost circuit and the way the JFET is biased.

There's also an extra 3.3 uF coupling capacitor in the 800RB signal path that isn't present in the 400RB that would shave off some of the low-end.

A Greco RB-800 into a GK 800RB would be a shit-hot almost-palindromic bass rig.

I've been using a 400RB into a Road 18 cab for 25 years now. Play a Rick 4003. I love the low end and it never gets farty/wooly/muddy. The mids and highs also have the clarity and punch that the low end does. The boost knob gives a very nice fuller presence. I've had a lot of compliments on my bass "sound".

I used a second 400RB as a guitar head when I played the 6 string in a different band. It worked very well.

Nate Dort wrote: Mon Jun 26, 2023 1:06 pm A Greco RB-800 into a GK 800RB would be a shit-hot almost-palindromic bass rig.

I love that

Sometimes I go back and listen to something from when I had much less cool gear and money and I'm still pretty happy with what I got w/ a 400RB, SWR 4x10, and an MIJ P-Bass and would totally get along fine going back to all that.

Example of what I'm talking about: