Why not use a powered speaker instead of a guitar amp?

[rpjazzguitar]

You may be right - I've used a mixer for a long time and now my cabs accept instrument level, so I don't have that many knowledge on that subject. You'll need to to a little research.

I did a little research on the point you suggested.

The Yamaha mixer has a "rated level" of output of +4dbu -- pro line level. Output impedance is 150 ohms.

The ME80 pedalboard output is rated at -10dbu at 2k ohms. That's close to consumer line level (usually specified as -10dbv, which is a little different, but the ME80 manual says dbu).

The SRM350 powered speaker has a "sensitivity" of +4dbu when set to "Line". That's pro line level.

So, if "rated level" and "sensitivity" mean what it sounds like, the situation is clear.

The ME80 puts out about .25 volts and the Mackie powered speaker, set to "Line" wants 1.23 volts.

The Yamaha Mixer's first stage is labeled "Gain" and will accommodate a wide range of levels. But, whatever you put in, the rated output is +4dbu. So, that's why it works. The mixer takes the .25 volts and amplifies it by nearly a factor of 5, which is 14db.

The ME80's output impedance is 2k ohms. A typical mic is lower (30 to 600 is the range I found online). So, if the Mackie Mic input is really expecting a low impedance mic -- (the manual doesn't say this, but what else would you expect?), then there's an impedance mismatch of somewhere between 3.3x and 70x. And, that mismatch should attenuate the highs, which will make the lows sound more prominent. That's what I heard when I tried it -- and Nevershouldetc had already explained.

So, the solution is now clear. A preamplifier in the signal chain, OR, a powered speaker that can accommodate a consumer line level signal.

The Bose S1 manual does not contain the relevant specs. Neither does the Alto FX310 manual. The Bose L1 (line array) manual mentions a 1/4" input for guitar.

The mixer (or other preamplifier) gets the signal at the correct level. Then there's the issue of perceived iciness or sterility. Seems like 7 bands of EQ with gain might do the trick, but I'll have to try it. If it works, my rig is pedalboard (which I use anyway) to a Boss GE7 or similar into the appropriate size of powered speaker for the venue.

EDIT: The GE7 apparently it starts at -20dbu (nominal input rating), not -10dbu, so outputing at pro line level is a 24 dbu increase, which is more than the spec says it can do. If you start with a louder input signal (say, 10dbu), it isn't clear to me what will happen, but certainly distortion is a possibility.

[jorgemg1984]

I did a little research on the point you suggested.

The Yamaha mixer has a "rated level" of output of +4dbu -- pro line level. Output impedance is 150 ohms.

The ME80 pedalboard output is rated at -10dbu at 2k ohms. That's consumer line level.

The SRM350 powered speaker has a "sensitivity" of +4dbu when set to "Line". That's pro line level.

So, if "rated level" and "sensitivity" mean what it sounds like, the situation is clear.

The ME80 puts out about .25 volts and the Mackie powered speaker, set to "Line" wants 1.23 volts.

The Yamaha Mixer's first stage is labeled "Gain" and will accommodate a wide range of levels. But, whatever you put in, the rated output is +4dbu. So, that's why it works. The mixer takes the .25 volts and amplifies it by nearly a factor of 5, which is 14db.

The ME80's output impedance is 2k ohms. A typical mic is lower (30 to 600 is the range I found online). So, if the Mackie Mic input is really expecting a low impedance mic -- the manual doesn't say this, but what else would you expect?), then there's an impedance mismatch of somewhere between 3.3x and 70x. And, that mismatch should attenuate the highs, which will make the lows sound more prominent. That's what I heard when I tried it -- and Nevershouldetc had already explained.

So, the solution is now clear. A preamplifier in the signal chain, OR, a powered speaker that can accommodate a consumer line level signal.

The Bose S1 manual does not contain the relevant specs. Neither does the Alto FX310 manual. The Bose L1 (line array) manual mentions a 1/4" input for guitar.

That much gets the signal at the correct level. Then there's the issue of perceived iciness or sterility. Seems like 7 bands of EQ with gain might do the trick, but I'll have to try it. If it works, my rig is pedalboard (which I use anyway) to a Boss GE7 or similar into the appropriate size of powered speaker for the venue.

That makes sense, hope you find something that works!

[rpjazzguitar]

That makes sense, hope you find something that works!

Thanks! I appreciate the help thinking it through.

[bozobreak]

I have a regular Sunday jam session where I only bring this setup.
I use one of the wedges available on the stage, going from the ParaEq directly to the active, powered speaker.
It uses a powerbank sold for phones, with USB to 9VDC converter.

[sgosnell]

I've used the power bank and 5V to 9V converter cable method. It works fine, but I generally use a rechargeable 9V battery in a cheap portable enclosure. I have a converter cable I made up to change the voltage polarity to center negative, but I generally rewire the enclosure by cutting and resoldering the wires, positive to negative and vice versa to give center negative. Any of these methods work fine, it's just a matter of what is convenient at the time.

[aquin43]

So, there is a whole industry making guitar loudspeakers with carefully designed cone breakup which they claim is the essence of "guitar tone" and it seems that for practical purposes it can all be replaced by a bit of EQ :-)

[rpjazzguitar]

So, there is a whole industry making guitar loudspeakers with carefully designed cone breakup which they claim is the essence of "guitar tone" and it seems that for practical purposes it can all be replaced by a bit of EQ :-)

I was assuming that the powered speaker idea would be for a clean-tone rig. I don't think it's going to sound like Santana's Mesa Boogie.

But, it might sound quite a bit like a Henriksen Bud/Blu, since they reportedly sound good on vocals.

I'm not suggesting that a tube amp won't sound better, but it may not sound better per pound. And it may sound terrible up a long flight of stairs.

[pingu]

1300659[/URL]]I was assuming that the powered speaker idea would be for a clean-tone rig. I don't think it's going to sound like Santana's Mesa Boogie.

But, it might sound quite a bit like a Henriksen Bud/Blu, since they reportedly sound good on vocals.

I'm not suggesting that a tube amp won't sound better, but it may not sound better per pound. And it may sound terrible up a long flight of stairs.

Your last line is on point
(and very funny!)

[pingu]

Harley Benton PowerPlant Powerbank – Thomann UK

I got one of these
its works fine

[John A.]

I was assuming that the powered speaker idea would be for a clean-tone rig. I don't think it's going to sound like Santana's Mesa Boogie.

But, it might sound quite a bit like a Henriksen Bud/Blu, since they reportedly sound good on vocals.

I'm not suggesting that a tube amp won't sound better, but it may not sound better per pound. And it may sound terrible up a long flight of stairs.

How many pounds are you willing to carry, up how many steps?

[rpjazzguitar]

How many pounds are you willing to carry, up how many steps?

To give this a serious answer, most places these days are ADA compliant, meaning that there is access for wheelchairs.

But, one place I play has a kind of lift by the front steps that looks like it hasn't been used in years. Clearly installed in response to the ADA.

So, I'm supposed to arrive with all my stuff on a cart and leave it unattended on the street while I try to get a bartender's attention in a packed bar? It's unclear to me how a person in a wheelchair is supposed to do it. Maybe there's a call button, but I didn't see it.

What I really want is the guitar on my back, a tiny loud-enough amp and one rolling case for everything else. One trip. But it's a loud bar, which means I bring the powered speaker and my mixer for the preamplication. So, I'm thinking about a smaller, simpler preamp and a small powered speaker.

[Spook410]

I did a little research on the point you suggested.

The Yamaha mixer has a "rated level" of output of +4dbu ... (and a bunch of other good stuff)

I see you've gone down the rabbit hole of 'levels' since you've started experimenting with the Mackie and you probably know more than most of us now. We should all be issued a laminate card with all the levels with every guitar purchase.

For those thinking on all this and daunted by the array of levels, you can convert anything to anything. My $27 Beringer instrument level to balanced mic level works great. Since it is stepping down the signal it just uses a transformer and is a passive (unpowered) device. You can however get boxes that are powered to take a guitar instrument level up to pro line level. Or, you can use a mixer with an instrument input. There are DI's, Line Extenders, and converters. Radial Engineering, though expensive, probably makes the best though they seem kind of focused on DI (mic level).

In addition.. many speakers are happy with a line level (as opposed to pro line level) and that's available in a balanced out on some amp modelers / cabinet modelers. I'm running a Joyo American ($35) to a Joyo Cab Modeler ($150) right now that has a balanced line level out and it works fine. It's also a setup that's hard to put down.. my Strymon Iridium board is drawing dust.

As for powered speakers, an FRFR does everything. A guitar combo does one thing. And as electronics are rapidly evolving to cover gigging, home recording, and quiet practice seems it would be nice to take advantage.

[Spook410]

I'm not suggesting that a tube amp won't sound better, but it may not sound better per pound. And it may sound terrible up a long flight of stairs.

Ha!

This would make a good sign.

[rpjazzguitar]

I see you've gone down the rabbit hole of 'levels' since you've started experimenting with the Mackie and you probably know more than most of us now. We should all be issued a laminate card with all the levels with every guitar purchase.

For those thinking on all this and daunted by the array of levels, you can convert anything to anything. My $27 Beringer instrument level to balanced mic level works great. Since it is stepping down the signal it just uses a transformer and is a passive (unpowered) device. You can however get boxes that are powered to take a guitar instrument level up to pro line level. Or, you can use a mixer with an instrument input. There are DI's, Line Extenders, and converters. Radial Engineering, though expensive, probably makes the best though they seem kind of focused on DI (mic level).

In addition.. many speakers are happy with a line level (as opposed to pro line level) and that's available in a balanced out on some amp modelers / cabinet modelers. I'm running a Joyo American ($35) to a Joyo Cab Modeler ($150) right now that has a balanced line level out and it works fine. It's also a setup that's hard to put down.. my Strymon Iridium board is drawing dust.

As for powered speakers, an FRFR does everything. A guitar combo does one thing. And as electronics are rapidly evolving to cover gigging, home recording, and quiet practice seems it would be nice to take advantage.

I appreciate this info and will take a look at the Joyo products. Others have recommended them too.

After the rabbit-dive, I learned this: The ME80 doesn't put out enough volts for the SRM350 on the "line" setting.

The ME80 does put out enough volts for the "mic" setting, but it doesn't sound good. That's because of an impedance mismatch. Impedance can be thought of as the romantic magic between two people in love. You can't put it into words, but you know if it's wrong.
So, no "mic" setting.

Then, there are a series of products which will do the voltage matching, but none of them are called "voltage matchers". They're called, variously, mixers, preamps, active DIs, modelers or still less informative names. Most of them do a bunch of other things more of interest to the patent clerk than the simpleton trying to find more volts for his SRM350.

[garybaldy]

Apparently you can use the 'mix' output of the infamous Bad Monkey straight into a PA. It's supposed to create a tube like sound. The OD does not have to be engaged. I have one but haven't tried it. I'd probably put an eq in front of it. I have used a Fishman Platinum bass eq for guitar and it works well.

[Hammertone]

Inspired by Jaco Pastorius' use of the Acoustic 360/361 powered cab, I've put together a couple of slightly smaller rigs that each have a little power amp velcro'd to the floor of an open-back cab. I run them with a pre-amp pedal of one sort or another, and they sound great. I can use the cab flavour of my choice, which is much lighter than similar-sized combos, and is dead easy to transport and use on gigs.

Here's a preamp pedal on a couple of different, smaller cabs, and a photo that shows the size of the little 75-watt Class D Hotone power amp. Sounds great!

[rpjazzguitar]

Apparently you can use the 'mix' output of the infamous Bad Monkey straight into a PA. It's supposed to create a tube like sound. The OD does not have to be engaged. I have one but haven't tried it. I'd probably put an eq in front of it. I have used a Fishman Platinum bass eq for guitar and it works well.

Is there any problem going from the device to the PA with a unbalanced 1/4" cable?

I thought, for some reason, that it is better to use XLR for lower noise.

[nevershouldhavesoldit]

Is there any problem going from the device to the PA with a unbalanced 1/4" cable?

I thought, for some reason, that it is better to use XLR for lower noise.

If both the XLR output and the XLR input being connected are truly balanced, there will be better isolation from noise. But unless you’re in an electrically noisy environment or have noisy power lines, you probably won’t notice any difference in live performance unless you’re running very long cables (like 100’).

[pauln]

The Yamaha mixer has a "rated level" of output of +4dbu -- pro line level. Output impedance is 150 ohms.

The ME80 pedalboard output is rated at -10dbu at 2k ohms. That's close to consumer line level (usually specified as -10dbv, which is a little different, but the ME80 manual says dbu).

The SRM350 powered speaker has a "sensitivity" of +4dbu when set to "Line". That's pro line level.

So, if "rated level" and "sensitivity" mean what it sounds like, the situation is clear.

The ME80 puts out about .25 volts and the Mackie powered speaker, set to "Line" wants 1.23 volts.

dBv and dBu are the same thing, since 0 dBu is 0.775 Vrms 600-Ohm load 1 wm (0 dBm is 1 mw) which is the same as 0 dBv, and the same as -2.218 dBV (where 0 dbV is 1 Vrms any load).

Input sensitivity is the input voltage at which the gain stage produces full rated output power. Rated output is maximum level before onset of specified distortion at which further clean headroom is unavailable. You never exceed the sensitivity specification, but must attenuate the input signal to have headroom well below rated output (headroom for professional recordings is historically about 12 dB "fast peaks" above average level).

In a series of gain stages the usual process is to start at the final stage and determine the maximum input or output level based on how much dynamic headroom you require and attenuate it in the previous stage. If you know two of the three specifications (input sensitivity, gain factor, rated output) you can calculate the one you don't know from which to subtract, or estimate it from the clipping lights.

Then repeat with the previous stage to make sure it also has headroom with its input levels. In an integrated unit of stages the rated outputs and sensitivities will be properly scaled already, not only to avoid losing headroom but also to prevent lifting the noise floor through the stages.

With the specs, some math, and some testing as you are doing, you're getting there.

[Spook410]

For those so inclined.. did like the 'dB or not dB' suggestion for the title of the article. And lots of churn in the comments.

https://www.edn.com/audio-levels-dbu...-need-to-know/

[rpjazzguitar]

dBv and dBu are the same thing, since 0 dBu is 0.775 Vrms 600-Ohm load 1 wm (0 dBm is 1 mw) which is the same as 0 dBv, and the same as -2.218 dBV (where 0 dbV is 1 Vrms any load).

Input sensitivity is the input voltage at which the gain stage produces full rated output power. Rated output is maximum level before onset of specified distortion at which further clean headroom is unavailable. You never exceed the sensitivity specification, but must attenuate the input signal to have headroom well below rated output (headroom for professional recordings is historically about 12 dB "fast peaks" above average level).

In a series of gain stages the usual process is to start at the final stage and determine the maximum input or output level based on how much dynamic headroom you require and attenuate it in the previous stage. If you know two of the three specifications (input sensitivity, gain factor, rated output) you can calculate the one you don't know from which to subtract, or estimate it from the clipping lights.

Then repeat with the previous stage to make sure it also has headroom with its input levels. In an integrated unit of stages the rated outputs and sensitivities will be properly scaled already, not only to avoid losing headroom but also to prevent lifting the noise floor through the stages.

With the specs, some math, and some testing as you are doing, you're getting there.

Consumer line level is -10dbV. I erred in writing dbv. Thanks for pointing this out.

[garybaldy]

Is there any problem going from the device to the PA with a unbalanced 1/4" cable?

I thought, for some reason, that it is better to use XLR for lower noise.

I'm sorry I don't know. My limited info was found on the web. I'm currently now taking my BM with me to rock gigs just incase my MM 65RP fails. And with fingers crossed!
PS. I suppose I've always thought a 1/4" jack into a mixer would be ok because they have 1/4" sockets. Back in the day all our mics had jacks. I may have forgotten about noise issues then. In those days as long as stuff worked all was good!! Happy times!

[jorgemg1984]

Is there any problem going from the device to the PA with a unbalanced 1/4" cable?

I thought, for some reason, that it is better to use XLR for lower noise.

I my experience, if you use single coils and play in venus that are located on old buildings, the xlr can certainly make a difference. Also, if you run long cables, you'll loose less treble frequencies.

Apart from that, I've found three reasons to use XLR instead of Jack (ts unbalanced) outputs:

1) you need to send less volume, as the xlr inputs expect mic level - depending on your gear, that can be a good thing.

2) even if we're talking about very cheap mixers, I've found the mic preamps present in xlr inputs to help with the sound

3) where I live at least, when the mixer is far from the stage, you have what here i called a "stage box", where you connect rour rig and that box connects everything to the maix mixer - and all stage boxes I found until today were xlr exclusive.

[garybaldy]

Apart from that, I've found three reasons to use XLR instead of Jack (ts unbalanced) outputs:

1) you need to send less volume, as the xlr inputs expect mic level - depending on your gear, that can be a good thing.

Is that still the case with (modern?) XLR inputs that have a jack input down the centre? Sorry I'm not tech savvy.

[jorgemg1984]

Is that still the chase with (modern?) XLR inputs that have a jack input down the centre? Sorry I'm not tech savvy.

That's an excellent question, no idea, maybe it depends on the implementation? Actually my Mambo PA cabs have a dual xlr/jack input, not sure how it adjusts to gain input, since I never had neither distortion neither lack of volume.