Hi Folks,
New member here.
I'm looking to build, or maybe buy, a small portable stereo combo amp for a digital piano/ synth. The closest thing to what I'm looking for is probably the Roland KC 220, but I dont want to spend €550 on it and I don't need it to be battery powered.
For whatever reason, most keyboard amp manufacturers don't make stereo amps and so if you want stereo you have to buy two and most people use active PA speakers anyway as they tend to be much better. This is unfortunate as most modern digital pianos sound rubbish in mono, even when summing the left and right together.
I want something to take along to a small jazz and blues group practice. It doesn't have to be high power and I'd like something as light as possible. I currently have a few options available, but they're all too big, too powerful and too heavy. For instance I have a Warwick Goblin bass head which is 200w and smaller and lighter than a Jack Reacher novel (and not as many people die horribly when I use it), but it's mono and the cab I use with it is a 4x8 that weighs 30 kg.
I'm thinking of building a small speaker cab, with maybe two midrange speakers to give the stereo and a shared woofer. Probably 2x 4 plus an 8 or a 10. I'd then buy a small class D stereo power amp module to drive it, or maybe a second Goblin. I only really need 20 or 30 W rms per side, probably even less.
I could either sum the L & R signals via a crossover for the woofer, or just drive it (with x over) from my left channel.
Has anybody got any advice on the cab ? Good idea or dumb ?
New member here.
I'm looking to build, or maybe buy, a small portable stereo combo amp for a digital piano/ synth. The closest thing to what I'm looking for is probably the Roland KC 220, but I dont want to spend €550 on it and I don't need it to be battery powered.
For whatever reason, most keyboard amp manufacturers don't make stereo amps and so if you want stereo you have to buy two and most people use active PA speakers anyway as they tend to be much better. This is unfortunate as most modern digital pianos sound rubbish in mono, even when summing the left and right together.
I want something to take along to a small jazz and blues group practice. It doesn't have to be high power and I'd like something as light as possible. I currently have a few options available, but they're all too big, too powerful and too heavy. For instance I have a Warwick Goblin bass head which is 200w and smaller and lighter than a Jack Reacher novel (and not as many people die horribly when I use it), but it's mono and the cab I use with it is a 4x8 that weighs 30 kg.
I'm thinking of building a small speaker cab, with maybe two midrange speakers to give the stereo and a shared woofer. Probably 2x 4 plus an 8 or a 10. I'd then buy a small class D stereo power amp module to drive it, or maybe a second Goblin. I only really need 20 or 30 W rms per side, probably even less.
I could either sum the L & R signals via a crossover for the woofer, or just drive it (with x over) from my left channel.
Has anybody got any advice on the cab ? Good idea or dumb ?
As I assume you need the stereo for whatever the stereo effect is generated by the keyboard, then summing that for only certain frequencies would probably cause some audible, unusual artifacts.
If it were me I would pursue either a mono system for playing the keyboard as mono, or just use 2 mono combo amps. If stereo and DIY are non-negotiable, I would just find a suitable design and make 2 channels of it in 1 physical cab.
If it were me I would pursue either a mono system for playing the keyboard as mono, or just use 2 mono combo amps. If stereo and DIY are non-negotiable, I would just find a suitable design and make 2 channels of it in 1 physical cab.
Find a sound bar, hack the supply to use DC, use rechargeable cells , that should work.
Or get two 'party speaker', one for each channel.
Or try building your own, plenty of choice in plate amps.
Or get two 'party speaker', one for each channel.
Or try building your own, plenty of choice in plate amps.
Thanks leadbelly. DIY is certainly negotiable, I just thought that given the name of this website it may have been mandatory 😀. One option that I'm thinking of is building 2 of these in the link below (as seperate cabs) and either buy another Warwick Gnome or use a smaller stereo hifi power amp, of which I have a few lying around the house ....(Linn LK140, an old Arcam etc) to drive them. I could even buy a small stereo PA amp, but am reluctant to, given what I have lying about.
However the twin Gnome option would give me a lot of flexibility up to a stereo 200w per channel, using my 4x8 should I ever need it.
https://www.basschat.co.uk/topic/455858-house-jam-micro-cab/
Thanks Naresh, that's certainly an option. I do have an unused Linn Komponent centre speaker which I could possibly use as it has seperate speaker terminals on the back for each of the 4 drivers.
I could also just sell it and buy something....but where's the fun in that ?
I could also just sell it and buy something....but where's the fun in that ?
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The Blackstar Fly 3 Acoustic stereo combo is super lightweight, might be enough for practice as is, though you could add a subwoofer if it wasn't enough:
https://blackstaramps.com/wp-content/uploads/2021/08/fly-3-acoustic-handbook.pdf
For the price, it would be hard to beat DIY, and you could probably listen to the combo somewhere near you to see if it is loud enough, the pair are probably around 93dB at one meter.
Thanks weltersys, that could be a good option. I'd never really considered the possibility of a small guitar practice amp, because I'd always thought they'd be too small to cope with the range from a full keyboard.
I've always liked the idea of the Spark amps, with their jamming capabilities. I may have a closer look at them, however as far as I know, none of them are stereo, which is important.
I've always liked the idea of the Spark amps, with their jamming capabilities. I may have a closer look at them, however as far as I know, none of them are stereo, which is important.
I couldn't be bothered to register at Basschat to download that project .pdf, but Winisd says for QB3 alignment that Fane driver needs a 8.4L box and about a 7" long 2.5" port, which is what I'm guessing the 68mm port cutout is for.
Thanks leadbelly. I didn't realise that you'd need to register to download it, but there's nothing in the pdf that's not on the thread anyhow, in whichever post the guy pasted the drawings. You're pretty much spot on with the dimensions for the box and the port.