Pre-amp and power vs a head

[Nickthebass]

Ok Talkbass hive-mind I need some help

I'm looking for thoughts, recommendations, pros and cons of moving to a pre-amp / power amp rig rather than a head.

I have a small pedal board based around an Origin Effects BassRig SV to get "my sound" which is sent to both the front of house and back-line. I'm currently running a pair of Barefaced cabs powered by either an Ashdown ABM600 or a GB Streamliner 900 but I'm considering replacing the head(s) with a power amp and a graphic EQ (or similar).

The back-line rack would only need to deal with volume and the oddities of the room. The pedal board deals with tone shaping, compression, drive and all that. I'm giving FOH a "finished" sound for them to balance / tweak to the room and mix and want to do the same with my back line.

Someone in TB has probably been down this (or a similar road) before but it would be totally new to me. Any thoughts on power-amps to check out (or avoid), similarly rack-mount EQs (or similar) as well as any bigcompromises / issues that people have bumped into?

 

[Solude]

They both have loops and line ins. You already have power amps

 

[Wasnex]

An important consideration is level matching. Pedals generally work at instrument level and power amps and effects loops generally work at line level, which is much hotter.

Normally you compare the max output level coming from the pedals to the sensitivity rating of the power amp. The max output should ideally be hotter.

I checked the Origin Effects and AFAIK it does indicate Max output but it does indicate the Amp Out can be connected to an amp or power amp. Much better if you can get the actual Max output, as the Sensitivity rating varies from power amp to power amp.

Unless you need more EQ than is provide by the pedal board, I would not bother with rack EQ. Keep in mind rack effects also tend to run at line level. Years ago I used a 31-band rack EQ with an SWR RedHead. The EQ was patched into the amp's effects loop.

I have used various rack-based rigs. They suited my touring needs but tended to be too big and heavy for most players needs. The reason they worked for my touring needs is because we packed all of our gear into a cargo truck with a lift gate. So it was rarely necessary to lift the rack. It had casters, so we mostly rolled it around. When it was necessary to lift, it took two people.

I have an old GK 700RB/112 combo that I used for gigs in local venues. For this type of gig I packed and transported my own gear to and from the venue in a small car, so the rack rig was not appropriate.

The last rack I used was 16SP. Not all of the spaces were used, but that was a good height to serve as my speaker stand (YMMV). I had a QSC USA 900 power amp in the bottom, a Ashely MX508 rack mixer in the middle. It also had a rack tuner, a Furman rack power conditioner with lights, and a 2- or 3- space rack drawer to hold cables, DIs, and a set of strings, etc.

 

[Nickthebass]

They both have loops and line ins. You already have power amps

Yup - but if I send the BassRig’s out to the amp’s the loop then I bypass the amp’s EQ.

I’m aiming to come out of the BassRig and into a “room tuning” back line EQ before the power amp. I can (and do) this by running into the front of my current amp(s) but I’m looking to see if there is a better solution.

bass -> compressor -> BassRig -> “room eq unit”-> power amp

 

[Nickthebass]

An important consideration is level matching. Pedals generally work at instrument level and power amps and effects loops generally work at line level, which is much hotter.

Normally you compare the max output level coming from the pedals to the sensitivity rating of the power amp. The max output should ideally be hotter.

I checked the Origin Effects and AFAIK it does indicate Max output but it does indicate the Amp Out can be connected to an amp or power amp. Much better if you can get the actual Max output, as the Sensitivity rating varies from power amp to power amp.

Unless you need more EQ than is provide by the pedal board, I would not bother with rack EQ. Keep in mind rack effects also tend to run at line level. Years ago I used a 31-band rack EQ with an SWR RedHead. The EQ was patched into the amp's effects loop.

I have used various rack-based rigs. They suited my touring needs but tended to be too big and heavy for most players needs. The reason they worked for my touring needs is because we packed all of our gear into a cargo truck with a lift gate. So it was rarely necessary to lift the rack. It had casters, so we mostly rolled it around. When it was necessary to lift, it took two people.

I have an old GK 700RB/112 combo that I used for gigs in local venues. For this type of gig I packed and transported my own gear to and from the venue in a small car, so the rack rig was not appropriate.

The last rack I used was 16SP. Not all of the spaces were used, but that was a good height to serve as my speaker stand (YMMV). I had a QSC USA 900 power amp in the bottom, a Ashely MX508 rack mixer in the middle. It also had a rack tuner, a Furman rack power conditioner with lights, and a 2- or 3- space rack drawer to hold cables, DIs, and a set of strings, etc.

This sounds like a big boy version of what I had in mind.

Yes - I would want more EQ than coming off the pedal board - but it is there just to deal with the room as / when needed so that I’m not compromising what I’m doing on the pedal board.

 

[Wasnex]

Yup - but if I send the BassRig’s out to the amp’s the loop then I bypass the amp’s EQ.

I’m aiming to come out of the BassRig and into a “room tuning” back line EQ before the power amp. I can (and do) this by running into the front of my current amp(s) but I’m looking to see if there is a better solution.

bass -> compressor -> BassRig -> “room eq unit”-> power amp

Most of the PAs I have run placed the system EQs in inserts on the boards. Inserts are essentially loops.

You can also run the EQs inline with the power amp, or you can use a programmable speaker processor that has EQ, time delay, etc.

Personally I think it would be better to get a different preamp that allows you to adjust your stage sound.

If you with a rack EQ consider 31-band graphic or full parametric with four our more bands. This sort of rack gear is nowhere near as common as it used to be because it's generally better to with a digital mixer rather than using an analog board and separates for processing.

 

[Wasnex]

Probably still lot's of used rack gear available cheap from the golden days. I checked Sweetwater. They have a mono DBX 31-band graphic for $235, that should work well. They have tons of parametric options, but these are generally more intended for studio applications and many of them are very expensive.

 

[agedhorse]

Yup - but if I send the BassRig’s out to the amp’s the loop then I bypass the amp’s EQ.

That's exactly the point, you bypass the amp's inherent voicing and eq and use the amp as a power amp. via the effects return jack This is especially true for amps that are more heavily voiced (like the Streamliner and the Ashdown). If you really need an eq, I would suggest a pedal based eq placed between the preamp's output and the effects return input, most of these operate about 10dB below the +4dBu line level and are a good compromise. Since the master volume then functions as a power amp sensitivity control, it's best operated on amps like the Streamliner, Magellan and Subway models at between 2:00 and 3:00 which should put the sensitivity solidly in the ballpark.

 

[Nickthebass]

That's exactly the point, you bypass the amp's inherent voicing and eq and use the amp as a power amp. via the effects return jack This is especially true for amps that are more heavily voiced (like the Streamliner and the Ashdown). If you really need an eq, I would suggest a pedal based eq placed between the preamp's output and the effects return input, most of these operate about 10dB below the +4dBu line level and are a good compromise. Since the master volume then functions as a power amp sensitivity control, it's best operated on amps like the Streamliner, Magellan and Subway models at between 2:00 and 3:00 which should put the sensitivity solidly in the ballpark.

That all makes sense. Thank you! It feels like a bit of a work around using the amps that I have.

Phrasing the question differently.

I have a sound from the BassRig that I like. I want to the send that to another EQ stage to deal with the room and then to a power amp.

Is a neutral(ish) sounding bass head the best solution or is there a “something” into a power amp combination that would work better?

 

[Nickthebass]

Most of the PAs I have run placed the system EQs in inserts on the boards. Inserts are essentially loops.

You can also run the EQs inline with the power amp, or you can use a programmable speaker processor that has EQ, time delay, etc.

Personally I think it would be better to get a different preamp that allows you to adjust your stage sound.

If you with a rack EQ consider 31-band graphic or full parametric with four our more bands. This sort of rack gear is nowhere near as common as it used to be because it's generally better to with a digital mixer rather than using an analog board and separates for processing.

Ok - this is the sort of thing I had in my head. Sounds like a rackmout graphic may not be the best option.

Also I have no experience of PA style power amps (hence tapping up the TalkBass hive mind)! I feel like I just want a single volume knob but all the units I’ve seen have been designed for stereo systems.

 

[Wasnex]

That all makes sense. Thank you! It feels like a bit of a work around using the amps that I have.

Phrasing the question differently.

I have a sound from the BassRig that I like. I want to the send that to another EQ stage to deal with the room and then to a power amp.

Is a neutral(ish) sounding bass head the best solution or is there a “something” into a power amp combination that would work better?

If you AB a bunch of pro power amps, you probably won't hear any difference between them as long as they are gain matched. The output sections of some bass amps also behave as "straight wire with gain". Meaning they do not impose their own character or color on the sound. My point is there may not be a significant difference, depending on the specific gear you choose

The best solution is the gear you prefer. I doesn't really matter which options I would choose. This means you need to experiment and decide for yourself. I don't think you would have asked the question if you were happy with your current choices. So try something else or lower your expectations.

Long term, lowering your expectations may be the best choice. In my experience it ranges from extremely difficult to impossible to get really a really good bass sound live. Even if your gear can produce the perfect sound, acoustics usually dominate a small distance from the cab. There is only so much you can do to overcome the degradation that results.

You may have a few more laps through the rabbit holes before you see the light. Enjoy the journey and and learn as much as you can.

 

[Wasnex]

Ok - this is the sort of thing I had in my head. Sounds like a rackmout graphic may not be the best option.

Also I have no experience of PA style power amps (hence tapping up the TalkBass hive mind)! I feel like I just want a single volume knob but all the units I’ve seen have been designed for stereo systems.

A rackmount graphic and power amp can work really well. But the resulting package tends to be fairly large and heavy. Also, using a rack EQ probably means you have to tweak controls in multiple locations, which can be a hassle. Ideally your tone controls would be on your pedal board.

 

[KevInDaBassment]

Is a neutral(ish) sounding bass head the best solution or is there a “something” into a power amp combination that would work better?

AgedHorse will definitely have superior advice to mine, but to throw in my 2-cents...you could achieve the same thing with a decent graphic EQ pedal IME. An MXR M108s, Boss GEB-7, or Whirlwind Bass 10 could probably fit the bill. You'd be able to make adjustments by your other pedals too, so if you want to make changes to room correction and your tone you wouldn't need to go back and forth between the board and your rack.

A couple hundred bucks (or less if you buy used) would be all you're out to possibly solve the problem for good. You could spring for a bigger unit (like a 31-band) if you feel it's necessary, but if I found myself in your shoes I'd just grab a solid EQ pedal and see how that rolls at your next gig.

 

[Zooberwerx]

I use rackmount pre’s and power amps (…I have a seemingly endless supply). Pass on the GEQ (pedal or rackmount) and get yourself something like a Tech 21 Q Strip. It’s all you’ll need plus it doubles as a DI.

Riis

 

[D.A.R.K.]

I’ve done this with more than a few rigs. A light weight power amp, either parametric or graphic eq (I prefer a parametric for less phasing issues that can occur from cheap graphic filters, used to use the Rane a lot) and if gain was necessary a small rack mixer. Ive also had preamp pedals with line level out, and enough signal to push an amp. Some power amps also have adjustable input sensitivity. More gear to haul, but very modular. Having a small rack was better for me, than having a couple loose amplifiers and using their effects returns. There is some really svelt gear these days, you could do this with a 2 space shallow rack, with the right components.

 

[bherman]

That's exactly the point, you bypass the amp's inherent voicing and eq and use the amp as a power amp. via the effects return jack This is especially true for amps that are more heavily voiced (like the Streamliner and the Ashdown). If you really need an eq, I would suggest a pedal based eq placed between the preamp's output and the effects return input, most of these operate about 10dB below the +4dBu line level and are a good compromise. Since the master volume then functions as a power amp sensitivity control, it's best operated on amps like the Streamliner, Magellan and Subway models at between 2:00 and 3:00 which should put the sensitivity solidly in the ballpark.

Suggest that you take Andy's advice (as always) and stick with what you've got, but run it into the head's send/return loop to bypass the head's eq. I had an MXR10 band eq pedal on my board for a while (MXR 108S) and it was a very capable unit. For some dumb reason, I sold it. Only thing to be aware of is that it requires 18v power supply, but most pedalbd bricks these days have one. No need to go the rack route, come out of the bassrig into the MXR and then into the effects return on your head.

 

[hennessybass]

So...
Bass rig XLR ---> House PA
Bass rig 1/4" ---> (EQ used for room / cab adjustment) ---> power amp ---> cab


A graphic EQ / or Q/Strip pedal on the board would work in that spot, then you would just need power.
You could use your existing amp's effects return, or go with something like the Baby Sumo, or get a more neutral amp with just a little EQ (like the Quilter BB).

You could get a DSP version of something like a Crest Pro-Lite 2. It has parametric EQ, HPF, and some other stuff built in. Might really suck making adjustments - but if you don't tweek much, then it might be ok.

You could get a 3U rack, put a regular old power amp in there, and then something like the Summit Audio FeQ-50 in the other slot.
Summit Audio - FeQ-50

 

[Gizmot]

Using separate preamp and power amp allows you the flexibility to choose products that precisely meets your needs. You may not need this flexibility, but if you have the budget and the expertise, it can be exactly what you're looking for.

In comparing power amps to combo amps, you can absolutely buy more power and are more intolerant of load impedance. Going with separates allow you to side-step some of the performance compromises that are forced on combo amp manufacturers because of price.

Once upon a time, you would have to carry a much bigger, heavier electronics package, but there are a few rigs that can be put together in 2 or 3 rack spaces that aren't a lot heavier than some combos.

 

[dbsfgyd1]

Ok Talkbass hive-mind I need some help

I'm looking for thoughts, recommendations, pros and cons of moving to a pre-amp / power amp rig rather than a head.

I have a small pedal board based around an Origin Effects BassRig SV to get "my sound" which is sent to both the front of house and back-line. I'm currently running a pair of Barefaced cabs powered by either an Ashdown ABM600 or a GB Streamliner 900 but I'm considering replacing the head(s) with a power amp and a graphic EQ (or similar).

The back-line rack would only need to deal with volume and the oddities of the room. The pedal board deals with tone shaping, compression, drive and all that. I'm giving FOH a "finished" sound for them to balance / tweak to the room and mix and want to do the same with my back line.

Someone in TB has probably been down this (or a similar road) before but it would be totally new to me. Any thoughts on power-amps to check out (or avoid), similarly rack-mount EQs (or similar) as well as any bigcompromises / issues that people have bumped into?

I have a rack that I put together about 10 years ago. It has a stereo preamp as well as a stereo power amp. The preamp has a lot of what you have on you pedal board, less the drive component (the type of music I play doesn't require it). While it doesn't have a 7 band EQ, it does have a 3 band mid range parametric EQ which IMO
provides more than enough tone shaping for my needs. It also has optical compression, adjustable side chain for effects. What I was trying to accomplish was the ability to be able to plumb it up in as many different ways as possible.

The power amp has way more power (1250 watts) than anything I'll ever need, not to mention it has two very heavy transformers. Keep in mind, I bought this for using multiple cabs that may be different, bi-amping (pre-amp has a built in crossover) and such. It is absolutely an amazing sounding rig.

When I set it up my rig for the first time, my drummer (2 time Emmy award winner for sound production) goes "That is the biggest DI pedal I've ever seen. You do realize we have FOH support?" And we do. We hire a sound company for all our gigs, and being a vocal band with 5 singers plus horns, you can't get a good mix consistently without it.

What I've come to the conclusion of is that what sounds good on stage does not often translate to a good customer experience. We are paying our sound guys good money to create the best possible mix for the audience's benefit. The last thing I want to do it create stage wash that is going to give them a problem to work around, and it's so easy to do.

Consequently, in my quest for ultimate flexibility, I ended up with a whole lot of features and gear I don't use and or is outdated.

I really like my Eden WT-100 Navigator pre-amp. I recently bought a Mesa WD-800 which also has a 3 band midrange parametric EQ as well, but it's much more difficult to dial in. But, I've been playing around with using the Eden pre-amp fed into the effects return of the WD-800 which would mean a net reduction in the weight of the rack by 40 lbs by swapping out the Eden power amp. Just got to buy the rack ears.

 

[DonaldR]

If you always have FOH support, why not get a powered PA speaker? You would get the same sound that your are sending to FOH. That's what I do: no power amp nor graphic eq needed.