small amp for low B

[playswhatpays]

My Bassman 60 with a 12 does a decent job; and my SWR
WP 12 kills it (I had to replace the speaker with an Eminence Delta Pro eventually after I ran it hard.) I run the SWR for small stage situations, and after replacing the driver it will keep up with a band.

I think your real question is what inexpensive amp will reproduce lows decently. I may be wrong....

I would say most amps with a 12 will give you what you want. You're really looking for harmonics, and you can get that with most inexpensive 12 combos. Any smaller and you looking to pay some money for something that can deliver it. If I were you, I'd look at craigslist for some used deals.

 

[acmebass]

You will need to decide what constitutes 'handling' low B. Most practice amps will not reproduce low E. Some will reproduce the second harmonic, allowing the brain to fill in the fundamental. Not sure if that is 'handling' the low B or not. If it is then response to about 60Hz at practice levels is required. With keyboard accompaniment those practices will likely be fairly loud. A 15w (8-inch) amp is way short of handling low B and a 30w (10-inch) is not much better. You could replace the driver in the Rumble 30 with an Eminence Beta 10a and retune the cab for optimum performance. For a plug-n-play solution consider a GK MB112 or Ampeg BA112. The GK actually weighs less than the Rumble 30 and has a decent 12 inch driver and 200w amp. Cheaper amps will make some kind of sound in response to a low B, ranging from an outright fart to a sound that is at least somewhat musical. Best to try a few out, but I think you will find that the BA-112 and MB112 will meet your needs at relatively low cost. While you are trying amps out consider trying a big rig to hear what (2nd harmonic) low B should sound like - it will not likely bear much resemblance to the sound from the Rumble 15 or 30 (or most other entry level practice amps). Note that very few cabs are capable of reproducing low B with audible fundamental.

Thank you for pointing out the distinction between "handling" and "reproducing" the Low B fundamental. You are exactly right.

Thanks,
Andy

 

[acmebass]

+1

Acmes are very full range, as well as going accurately lower than just about anything else out there.

Acme B1 or B2.

Well, yeah. I wasn't going to say anything, but I don't think it will violate policy to agree with you...

Thanks,
Andy

 

[acmebass]

You want something that has an F3 around 60 Hz or lower.
This will give you good 1st harmonic (62 Hz) of the low B, but not much of the fundamental at 31 Hz.

If you are looking for a combo, I don't think you will find this.
Due to size (read: marketing concerns) the typical combo won't have much bottom end.
The Fender Rumbles are typical of this.
We use a Rumble 100 for an edrum machine, and it is completely gutless below 100 Hz.

Link Removed

A practice amp can provide very deep and rich response yet remain practical, because it does not have to make a lot of noise.

If you feel like rolling your own, an Eminence Legend BP102-8 combined with an Alpha 6a, and passive 500 Hz crossover will give you a nicely matched 2-way.
This is suitable for both bass and keys.

The 10" box is 3.97 cubic feet, F3=32 Hz, so it is a bit on the large side.
About 32" x 20" x 13" or equivalent.

If you will accept slightly less bass extension, reduce the box to 2.7 cubic feet, to get an F3 around 36 Hz.
Either will give you very generous bass extension.

I know you only want to help, bgavin, which we all appreciate, but you haven't actually built either of those, have you?

I'm suggesting that if you do, you might be in for a surprise.

Thanks,
Andy

 

[NaH]

My wife plays piano, I play keyboard/bass (both 4 and 5 string). When we rehearse, she'll play the keyboard when I'm playing bass. What we use is a set of powered reference speakers (such as M-Audio BX-5a) for keyboard and then a 12" combo for bass. I currently have a Markbass CMD 121p for practice (size is perfect and you can take it on gigs and have DI), though a while back I used a Peavey MAX 112 and it did well enough for practice. Obviously I like the Markbass better, but depends what you want to spend.

 

[bgavin]

I know you only want to help, bgavin, which we all appreciate, but you haven't actually built either of those, have you?

I'm suggesting that if you do, you might be in for a surprise.

Perhaps, but that requirement would silence nearly every poster on TB.

I build a lot of one-offs, for the proof of concept and my own entertainment.
So far, my RTA is fairly close to the predicted response.
Where I find the largest deviation is in the port calculations.
The end correction factors are crucial for projecting accurate tuning results.
Frankly, I have a lot more interest in horns than speaker-in-a-box redux.

For me, time is the most scarce commodity, and speaker design is simply a lifetime interest.
I make a far better living in the computer business, than I could ever make in the speaker business, hence the lack of time for building everything that interests me.

I would welcome posting of Acme RTA charts, if you are so inclined.
That would certainly add credence to the claims made for those boxes.
And we certainly appreciate your posting here and walking the fine line between information posting and self-promotion.
I've been penalized by the mods for this, and I'm not even in the speaker business...

 

[acmebass]

Perhaps, but that requirement would silence nearly every poster on TB.

And we certainly appreciate your posting here and walking the fine line between information posting and self-promotion.
I've been penalized by the mods for this, and I'm not even in the speaker business...

Thanks, Bgavin, I appreciate that, but I don't think I've done any promotion here at all. I know they frown on that, and other people seem to be willing to promote my stuff anyway.

Nor have I made any claims for the boxes, although Jasper383 said: "Acmes are very full range, as well as going accurately lower than just about anything else out there," which I appreciate. My 10" systems have been available since the '90's, and I don't think their capabilities are in question. I know there's a long thread or two about them on TB somewhere, although I haven't ever read them.

I use an LMS system, BTW, and there is plenty of information on my site. I'm not familiar with the True RTA setup, but it looks pretty cool, and not expensive.

You're right about trying to predict port dimensions using arithmetic, BTW. In the real world, sometimes it's pretty close, and sometimes not.

Thanks,
Andy

 

[AstroSonic]

Small can do low. They most likely will not be able to do it loud.

Look up Hoffman's Iron Law. Adapted by Theile Small there is not a single design that proves it wrong.

You want "small" and "low", you'll have to give up loudness.

Small and low is indeed possible, but it is neither automatic nor common as a design choice. It is a design decision followed by very few cab makers. Most seem to design for compact size and maximum driver size (that can fit on the front panel) - both decisions make it very difficult to get usable response (clearly audible reproduction of the tonic) to low E, let alone low B. Hoffman's Iron Law is the choice technical tool here, but the intervention of marketing decisions, as well as the lack of consumer knowledge seems to generally result in different decisions and resulting products. Many of these small combo's overall sound quite good and are useful as practice amps and even for low volume/small space gigs. However, it is unrealistic to expect usefully audible low B reproduction (even low E) at this budget level. IME, most do not even manage the second harmonic for low B or low E at reasonable practice levels.

I know that there are a lot of bass players who are quite pleased with their small combo's ability to 'handle' low B. The difference in audible impression between reproduction of low b with the low B tonic being reproduced and with only the second (or third harmonic) is profound. It's just that few players seem to know the difference (and they still make some great music). I suspect that if those folks heard actual reproduction of the tonic many of them would be looking for new cabs, although many, while hearing the difference, would still be satisfied with (or even prefer) their current rigs. The choice or preference for a rig tone lacking deep bass is a matter of personal preference. No right or wrong. And lets not forget that there is much more to good cab tone than deep bass extension, even if it is 'fundamental' (sorry . A discussion of the merits of deep bass extension in bass cabs is the basis for an entirely new thread. See for example the recent 'cabinet frequency response' thread.

The equipment being considered by the OP fairly clearly indicates that the cost of the equipment being considered is far below the cost of the Phil Jones and AER combo's (which are designed for bass extension in a small cab with lower sensitivity). In that budget (sub $150) arena there are few (if any) combo amps that opt for bass extension (over spl or size) even allowing usefully audible second harmonic reproduction of low B. Careful choice of a 12" combo in the $350-$500 range will allow passable low B (second harmonic) reproduction at practice levels. For low B reproduction with usefully audible reproduction of the tonic a Acme Low B-1 cab or a Fearful 12/6 flat pack driver kit (fromSpeaker Hardware) and a GK MB200 head would be cost effective alternatives. Buying second hand or DIY would of course be less expensive (provided the right choices are made).

 

[acmebass]

Small and low is indeed possible, but it is neither automatic nor common as a design choice. It is a design decision followed by very few cab makers. Most seem to design for compact size and maximum driver size (that can fit on the front panel) - both decisions make it very difficult to get usable response (clearly audible reproduction of the tonic) to low E, let alone low B. Hoffman's Iron Law is the choice technical tool here, but the intervention of marketing decisions, as well as the lack of consumer knowledge seems to generally result in different decisions and resulting products. Many of these small combo's overall sound quite good and are useful as practice amps and even for low volume/small space gigs. However, it is unrealistic to expect usefully audible low B reproduction (even low E) at this budget level. IME, most do not even manage the second harmonic for low B or low E at reasonable practice levels.

I know that there are a lot of bass players who are quite pleased with their small combo's ability to 'handle' low B. The difference in audible impression between reproduction of low b with the low B tonic being reproduced and with only the second (or third harmonic) is profound. It's just that few players seem to know the difference (and they still make some great music). I suspect that if those folks heard actual reproduction of the tonic many of them would be looking for new cabs, although many, while hearing the difference, would still be satisfied with (or even prefer) their current rigs. The choice or preference for a rig tone lacking deep bass is a matter of personal preference. No right or wrong. And lets not forget that there is much more to good cab tone than deep bass extension, even if it is 'fundamental' (sorry . A discussion of the merits of deep bass extension in bass cabs is the basis for an entirely new thread. See for example the recent 'cabinet frequency response' thread.

The equipment being considered by the OP fairly clearly indicates that the cost of the equipment being considered is far below the cost of the Phil Jones and AER combo's (which are designed for bass extension in a small cab with lower sensitivity). In that budget (sub $150) arena there are few (if any) combo amps that opt for bass extension (over spl or size) even allowing usefully audible second harmonic reproduction of low B. Careful choice of a 12" combo in the $350-$500 range will allow passable low B (second harmonic) reproduction at practice levels. For low B reproduction with usefully audible reproduction of the tonic a Acme Low B-1 cab or a Fearful 12/6 flat pack driver kit (fromSpeaker Hardware) and a GK MB200 head would be cost effective alternatives. Buying second hand or DIY would of course be less expensive (provided the right choices are made).

Very well said. I think you covered about everything.

Thanks,
Andy

 

[BlackThursday]

Based on my understanding that you desire to get some 31.5Hz into your daily regimen:

You aren't likely to find a cheap, small practice amp that will provide the absolute primal satisfaction waiting to be unleashed by the B-string on your 5'er, especially with a keyboard plugged-in as well. You could use headphones, both you and your wife, and while that might work it wouldn't be much fun (unless the two of you are into playing, ahem, "recording studio").

The Acme B1 has been astutely suggested and discussed here, and it is absolutely the smallest unit I have yet encountered that will do justice to not just the B, but the E-string as well. It works so well that I've owned one for many years and used it on a wide variety of gigs with upright and bass guitar. Not only that, but I've found it to be quite excellent for keyboards, synths, and acoustic instruments like mandolin, violin, and guitar. The downside is that, while very reasonably priced, its gonna be more expensive than a cheap practice amp. The upside is that it's vastly more useful, should you want to venture outside the rumpus room into the real world and put it to work. Oh, and you aren't likely to find better customer service. Of course, you'll need an amp, and there are some amazingly small, lightweight, inexpensive, and capable micros on the market. Together, you'd have a rig that will fit unobtrusively into your domestic lifestyle, give you what you wanted and paid for with extended low frequency response, and can be used in the real world without needing any excuses or apologies.

Pictured below are two of my own small rigs. In the right corner, weighing in at 37.5lbs, an Acme B1/AI Clarus. In the left corner, and included here for comparison purposes, weighing-in at a svelte 28lbs, a Phil Jones Briefcase (the PJB is about the smallest useful bass amp that I've found, a great little unit for what it is but it's no match for that B-string). The P bass behind them is there to provide a sense of scale and proportion.

Or, you could re-string your 5'er EADGC.

 

[acmebass]

Based on my understanding that you desire to get some 31.5Hz into your daily regimen:

You aren't likely to find a cheap, small practice amp that will provide the absolute primal satisfaction waiting to be unleashed by the B-string on your 5'er, especially with a keyboard plugged-in as well. You could use headphones, both you and your wife, and while that might work it wouldn't be much fun (unless the two of you are into playing, ahem, "recording studio").

The Acme B1 has been astutely suggested and discussed here, and it is absolutely the smallest unit I have yet encountered that will do justice to not just the B, but the E-string as well. It works so well that I've owned one for many years and used it on a wide variety of gigs with upright and bass guitar. Not only that, but I've found it to be quite excellent for keyboards, synths, and acoustic instruments like mandolin, violin, and guitar. The downside is that, while very reasonably priced, its gonna be more expensive than a cheap practice amp. The upside is that it's vastly more useful, should you want to venture outside the rumpus room into the real world and put it to work. Oh, and you aren't likely to find better customer service. Of course, you'll need an amp, and there are some amazingly small, lightweight, inexpensive, and capable micros on the market. Together, you'd have a rig that will fit unobtrusively into your domestic lifestyle, give you what you wanted and paid for with extended low frequency response, and can be used in the real world without needing any excuses or apologies.

Pictured below are two of my own small rigs. In the right corner, weighing in at 37.5lbs, an Acme B1/AI Clarus. In the left corner, and included here for comparison purposes, weighing-in at a svelte 28lbs, a Phil Jones Briefcase (the PJB is about the smallest useful bass amp that I've found, a great little unit for what it is but it's no match for that B-string). The P bass behind them is there to provide a sense of scale and proportion.

Or, you could re-string your 5'er EADGC.

Hey- thanks, man!

And you know, I don't want to pound on Phil Jones. I know he's sincere, and his cabs do what they do very well, and I actually like the way they sound- very clear and uncolored. But if low bass is what you want, you don't use 5" speakers, unless you're ready to EQ the heck out of them, as Bose does. I know there are plenty of players who don't care about the bottom half-octave, and that's fine, too.

Andy

 

[bgavin]

Thanks, Bgavin, I appreciate that, but I don't think I've done any promotion here at all. I know they frown on that, and other people seem to be willing to promote my stuff anyway.

I agree, but too often the vendors get the hairy eyeball from the Mods over some perceived violation of the rules.
My past chew-outs are amusing, considering I'm not a vendor.
No matter, all of us here are glad you stop by from time to time.

Right Now is a wonderful age for tinkering.
LMS and TRTA open doors today that used to closed to all but the highest budget engineers.
I remember when it took two of us to roll a 64k (!) chassis across the data center floor.
Today, my Blu-Ray player has more brains and storage..

I've read all your engineering papers time and again.
Thanks for making them available.

 

[unlined4string]

I also have had excellent results using an Acme Low B-1 with a good quality micro-head. It's overkill for practicing alone, but it also works very well gigging at low to moderate volume

Last weekend I played a restaurant jazz trio gig (piano/flute/bass) with a Low B-1 and TecAmp Puma 500. During break a bass player in the audience complimented me on the sound.

 

[acmebass]

I agree, but too often the vendors get the hairy eyeball from the Mods over some perceived violation of the rules.
My past chew-outs are amusing, considering I'm not a vendor.
No matter, all of us here are glad you stop by from time to time.

Right Now is a wonderful age for tinkering.
LMS and TRTA open doors today that used to closed to all but the highest budget engineers.
I remember when it took two of us to roll a 64k (!) chassis across the data center floor.
Today, my Blu-Ray player has more brains and storage..

I've read all your engineering papers time and again.
Thanks for making them available.

Thanks, Bgavin- I wasn't sure anybody ever looked at any of that stuff!

A

 

[acmebass]

I also have had excellent results using an Acme Low B-1 with a good quality micro-head. It's overkill for practicing alone, but it also works very well gigging at low to moderate volume

Last weekend I played a restaurant jazz trio gig (piano/flute/bass) with a Low B-1 and TecAmp Puma 500. During break a bass player in the audience complimented me on the sound.

It might have been your playing...

At any rate, glad you like the box!

Thanks,
Andy

 

[playswhatpays]

Wow, this is become so far off from the OP I don't even know what to say. I know Acme cabs are great, my dad owns one and raves about it. But come on, this guys talking about a Rumble 30. I highly doubt he's interested in spending $500 on a speaker cabinet. Take the Acme bass talk to a different thread.

 

[AstroSonic]

Wow, this is become so far off from the OP I don't even know what to say. I know Acme cabs are great, my dad owns one and raves about it. But come on, this guys talking about a Rumble 30. I highly doubt he's interested in spending $500 on a speaker cabinet. Take the Acme bass talk to a different thread.

You make a good point. $500 just for a cab would seem to be 'far off from the OP', yet It is spot on. The OP needed to understand what he was asking: He wants an amp/speaker capable of 'handling' low B, and at practice spls when accompanied by a keyboard, on the same amp. Two issues here: 1) 'handling' low B, and 2) when accompanied by a keyboard on the same amp/speaker.

There is a bass extension need, and there is a power need. Neither of these is likely to be met by a Rumble 30 (or other similar combos). It is possible for some small, inexpensive combos (like the rumble 30) to respond to low B with a sound that lets the player know that a note has been played and that conveys a sense of pitch. The latter is essential for the note to be musically useful. OTOH, the response is similar to that for B two octaves higher (because it lacks an audible tonic and second harmonic). It will lack punch, weight and other characteristics one gets from playing an octave or two lower.

Spending a about 2-3 hundred dollars more will get the second harmonic and enough power for keyboard accompaniment. Note that many (most?) cabs have very little more bass extension than this. They just allow higher spls. This level of reproduction provides a substantial improvement in its conveyance of the low b tone thanks to the brains ability to at least partially fill in (interpret might be more accurate) the missing tonic.

In order to actually reproduce the low B tonic (not necessarily at its full level) one must choose from only a select few cabs and then match it with a decent head. That's where the $500 comes in. To my knowledge there are no (assembled) cabs lower in cost that will reproduce the low B tonic at a usefully audible level. It would be great if some suggestions for alternatives were made. The Fearful 12/6 driver flatpack kit has already been mentioned.

 

[playswhatpays]

I understand your point, but we should keep our conversations to the point at hand and not to one which we want to take it. This thread should really be about inexpensive amps that can adequately handle a low b. Most 12 inch combos will produce the overtones needed to hear the b. I believe it is the most valid point made in this entire thread. There are a lot of threads here on TB, let's keep them relevant and resurrect ones that need resurrecting. I guess that's my point. I love the opinions and debates that go on here, but is just not the place for this particular one. It's more of a frequency response debate put into a cheap bass amp thread. Let's keep the matter at hand forefront.

Like I said previously, Acme is wonderful, but has no real relevance in this conversation.

 

[lowphatbass]

I would look for a used Roland KB-100 or KB-300. They have multiple inputs and have no problem handling a low B.

 

[acmebass]

Like I said previously, Acme is wonderful, but has no real relevance in this conversation.

Please explain what criterion you use when you decide whose posts are relevant, and whose are not. I'm afraid you lost me, and I'm not sure why it would matter to you anyway. I don't think anybody was trying to jerk the guy's chain, do you? If you go back and actually read the original post, I think you'd be hard pressed to explain how a loudspeaker which does exactly what he's looking for should not be allowed to be mentioned.

I'm new to this, and haven't seen this type of "soft censorship" before. But I'm willing to learn.

Thanks,
Andy