Does the amp matter when bypassing the preamp?

[Jay2U]

A well designed and built power-amp shouldn't add coloring to the tone. It's there to just amplify the signal without adding unnecessary distortion.

 

[NobodyImportant]

I’ve wondered this about the Harley Benton Block 800B. Use whatever else to color your tone and just have have a high power amp. I’ve been debating one as a backup amp.

 

[Blue Moose]

Similar experience here. My tone comes from my T21 VT, regardless of what amp I'm using. I quit running it through the front and plugged straight into the effects return. Bingo, the sound I wanted without the "dueling preamps."

We run everything FOH, so my amp is basically just a monitor. if I didn't already have so much usable gear lying around I'd go the powered cab route.

 

[N. Kentucky Bass]

Great tone, simple configuration. P-bass --> Noble preamp/DI --> PJB PB-300 powered cab and/or FOH

 

[RGerhart]

I have an Accugroove powered Tri112+ (12" speaker with a 6" mid-driver, plus tweeters), and I usually put my Noble DI or Aguilar DB680 to drive it. The powered cab route is the way to go, because the preamp really seems to make the most difference in tone. Being able to switch up preamps is an easy way to get different tones, while still using the same powerful, small cabinet night after night.

 

[agedhorse]

Just adding my experience to the discussion. A few months ago, the preamp on my Genzler Magellan 800 just stopped working. Might just be an issue with the input jack, but it's hard to tell. Everything is hardwired to the circuit board, so I'd have to spend a good amount of money sending it out to their service center and getting it repaired (past warranty). In the meantime, since the poweramp still appears to be functioning normally, I am using the receive input on the back with my HXStomp. Plenty of preamps/amps/cabsims/IR's to choose from and I'm liking it so far. To avoid the cost of shipping/repairs, I might just keep using the Stomp. I did really like the preamp on the Genzler head, so I'm not saying that the usage of the Stomp as a stand-in is "better", but I'm enjoying how it sounds and I'll probably just keep it this way. Again, just my current experience as it relates to the topic.

In this case, contact Jeff and arrange for your amp to be repaired. It’s repairable and not expensive to repair either (provided nobody got into it to try to fix it themselves).

 

[Old Garage-Bander]

I’ll say it again, powered cabs are the future.

and G&K had the Delorean.

 

[darwin-bass]

I read only page 1. Sorry if this is a repeat of other posts.

What affects a bass amp's sound? Well, everything does to some degree but I'd put the major players in this order.
1. Speaker & box design.
2. Preamp baked-in voicing. (EQ and high/low filtering)
3. Speaker placement
4. The room
5. Power amp.

I put the power amp so low on the list because I suspect most bass amps have power amps that are not much more than a wire with gain (hard to achieve, btw) and mostly rely on the preamp section for all the tone heavy lifting.

So if you can bypass the preamp in a handful of 500 watt heads and compare just the power amp sections driving the same speakers, I bet they all sound pretty much the same.

 

[darwin-bass]

Years ago I was in a high end stereo shop listening to some high end speakers. The salesman used his fancy patch board to switch power amps (separate pre & power amps). I didn't know what he did but I heard two things. 1 - The bass got tighter. 2 - The saxophone lower register became less muddy. When he said he had switched power amps I was surprised. I could attribute 1 to an increase in damping factor but 2 was something I would have never believed I'd hear comparing two high end power amps.

So, yes, there can be a difference. But no, the difference between power amps is very unlikely to be noticed in any sort of live setting, even by the bassist.

IMHO, of course.

 

[rickwick7600]

In this case, contact Jeff and arrange for your amp to be repaired. It’s repairable and not expensive to repair either (provided nobody got into it to try to fix it themselves).

We were in communication and he recommended I send it to their engineer in AZ. Said it shouldn't cost much more than $100 plus the shipping. I asked him for the address and how to get started, but he never got back to me. Probably just got busy. Not blaming him for missing it. Anyway, we're still looking at probably around $150 or more which may not be crazy expensive, but there are other things that cash can go towards right now. Plus this is my only amp. That's why I've just been resolved to use the HXStomp through the receive input since it sounds great. That's all I intended to convey with my post here on this thread as I thought it was relevant.

I want to be clear that this is not a complaint about Genzler products. I really like my amp plus my bass array 12-3 speaker, and I understand that with electronics stuff just goes wrong from time to time for various reasons. I may reach out in the future to get the repair.

 

[6-3-2]

Great tone, simple configuration. P-bass --> Noble preamp/DI --> PJB PB-300 powered cab and/or FOH

View attachment 4827688

This is a really smart and flexible set-up. I could easily see myself doing this. The prices for that cab are not bad at all either.

 

[bassbrad]

It depends on your amp and even more on the speaker you are using. There are some power amp sections that impart unique characteristics and others that are more accurate or transparent. Even more so arecthe different tonal characteristics of various types of speaker cabs used for bass.

Hearing my bass in the studio through that gear and those speakers was a revelation and since that time a part of me really was never going to be satisfied until I could achieve that sound quality live. That is why I'm now using powered PA speakers for my stage monitors instead of a traditional bass amp.
Still a part of me will always miss the grind, thump, rumble and sheer power of a great stage rig but I can no longer either wrestle or transport such a beast so I must find my solace.

 

[Zbysek]

I've recently stopped plugging into the front end of the amp altogether, and I'm going into the effects return with the +10db button engaged. The only controls on the front panel that work now are the power switch and master volume control.

Are you sure about this? I have early LMIII which is supposed to be very similar to LMII. When I plug into FX return, all EQ knobs affect the sound (the FX loop is placed pre eq).

 

[poochiecheeks]

I know some amps like the Quilter bass block 800 have a dedicated XLR in rather than an effects return, I could never tell any practical difference through that or the incredibly clean preamp section. I really liked it as it was like having a large power amp "pedal" on your board that didn't mess with your tone at all.

 

[HelpImaRock]

Are you sure about this? I have early LMIII which is supposed to be very similar to LMII. When I plug into FX return, all EQ knobs affect the sound (the FX loop is placed pre eq).

I just tried it again, and you're correct. The weird thing is the gain knob does nothing to the actual signal, but it does add hiss. So apparently, there is no point on this amp in going through the return. Which is disappointing. But something to look out for in the future when this thing eats it.

 

[agedhorse]

We were in communication and he recommended I send it to their engineer in AZ. Said it shouldn't cost much more than $100 plus the shipping. I asked him for the address and how to get started, but he never got back to me. Probably just got busy. Not blaming him for missing it. Anyway, we're still looking at probably around $150 or more which may not be crazy expensive, but there are other things that cash can go towards right now. Plus this is my only amp. That's why I've just been resolved to use the HXStomp through the receive input since it sounds great. That's all I intended to convey with my post here on this thread as I thought it was relevant.

I want to be clear that this is not a complaint about Genzler products. I really like my amp plus my bass array 12-3 speaker, and I understand that with electronics stuff just goes wrong from time to time for various reasons. I may reach out in the future to get the repair.

It's likely that the email or PM got lost, contact him again and he will help you get it sorted out.

 

[micguy]

Would love to do this, but we're a no-budget original band with half a PA for vocals in rehearsals.

So, you can buy a backup amp, or start aiming your purchases towards in ears and PA upgrades. How far do you want to go in music? Aim for where you want to be, not where you are already.

 

[crazyBassClown]

A pedal board and a powered cab is all most players really need.

But it's so much easier to adjust volume/tone with an amp on top of the cab than on a pedal on a pedalboard. This by itself is probably a significant reason powered cabs haven't caught on, especially now we have lightweight high power heads.

 

[Nephilymbass]

After nearly decade of getting a good tone, but not necessarily "my tone" through my Markbass LMII > GK NEO 115, I bought a BDDIv2. Plugged it in, turned some knobs, and there it was. "My tone." Why I couldn't do that with the head is a debate for a different time. (I got really close in comparison)

I've recently stopped plugging into the front end of the amp altogether, and I'm going into the effects return with the +10db button engaged. The only controls on the front panel that work now are the power switch and master volume control.

So it got me thinking, what happens when this amp finally meets its untimely demise? Is it worth getting another bass head? If so, other than build quality, does it matter what bass head? Would any cheapo Behringer do? Why not just buy a powered speaker instead?

I'm sure this has been done ad nauseam. But it's new for me so your thoughts are appreciated.

Been there. Yes the amp does matter some. If buying a another bass amp make sure it has either a “power amp in” or that the effects loop works the same as your current amp. Some amps have series effects loops, others have parallel, Some have an effects loop with a push button to run it either way. Some amps like my Mesa subway have an “aux in” which bypasses the preamp. If amp has a parallel effects loop you won’t be able to get the signal ratio dialed in. It’s kind of like using an amp with half the power and when you crank things up the signal to noise ratio suffers. Same goes for pa amps. Gotta make sure the input sensitivity works. For example when I was running my crown power amp my darkglass b7k ultra couldn’t drive the amp enough, I had to put an Avalon u5 which has a line level out between the darkglass and the power amp

 

[BluesWalker]

Maybe someone has already pointed this out, but unlike most other bass amps, MarkBass amps have a parallel effects loop. It essentially means that plugging a preamp into the effects return does not bypass the amp internal preamp; you get both instead. There is a thread on this forum that describes how one can change an internal jumper to get a series effects loop with a MarkBass amp.