powering an usb audio interface without a pc or laptop....

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Many modern usb audio interfaces (basically these are external soundcards) are designed to be connected directly to a PC or a laptop for both data and power.
Now, I have an Edirol ua-4FX which I'd like to use with a few 9v batteries or an usb battery pack - without the need for a laptop or a pc.
I tried to connect an usb battery pack with a fitting modified plug (usb type B) and I get no power into the Edirol ua-4FX - I've connected all the 4 wires accordingly...
Then, on reflection, I've noticed than none of the usb battery packs have a type B usb connector - is this a clue that it's basically impossible to feed this type of units unless one uses a computer or similar?

It's a real pity...something so close seems to be unreachable for some design oddities
Or are we just been presented with another clever gimmick to create more useless demands and therefore products? So one has to buy that unit for a computer and another similar to use with batteries?
 
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Red and Black wires in the cable are usually power at 5 Volts DC at 500mA rating.

You can use a wall plug with USB on it like as on the iPhone charger (other models also use this)

9V is too much, but you could go with 4.5V, possibly up to 6V to attach a made up battery pack. a 5v Zener diode inline would be a safer bet is going for the 6, 9 or even 12 volt option)
 
Red and Black wires in the cable are usually power at 5 Volts DC at 500mA rating.

You can use a wall plug with USB on it like as on the iPhone charger (other models also use this)

9V is too much, but you could go with 4.5V, possibly up to 6V to attach a made up battery pack. a 5v Zener diode inline would be a safer bet is going for the 6, 9 or even 12 volt option)

As I've mentioned: I've used one of those trendy usb battery pack with no luck - the one I have has 2 options: 500ma and 1a...it works fine with many usb power-able devices like iPod a Samsung smartphone and a minidisc too but plug this types of battery into an usb type B and it won't give any juice - that's really puzzling.
 
Ok here goes. Not quite sure I am understanding the question.

A USB type B certainly does carry Power as well as Data.

The current draw needed for your device is 360mA, So well within spec of any USB power supply, Battery included !

A USB A to B cable does connect From a laptop to your device. The same cable unplugged from your laptop would fit into any USB battery Pack. Are you looking for a battery pack that connects directly into this unit without an A to B Cable ? I cannot imagine there would be a big enough market to produce one.

Looking through the advanced manual online, there seems to be a normal and advanced mode on the device. Maybe try changing to Nowmal mode (options will be then limited) and try again.Now since this device seems to software driven via USB, I'm not too sure if it can be used without being connected to a PC (work stand alone if you will). Are you hoping to use it in a live setup without a pc in some place?

http://media.rolandus.com/manuals/UA-4FX_AG.pdf Applications Guide

http://media.rolandus.com/manuals/UA-4FX_OM.pdf Owners Manual
 
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yep...I'd like to use it while busking - plugging a dynamic balanced microphone (so no phantom 48v is necessary), another stereo binaural set of mics into the line in (this works because there is a small preamp boosting the signal) and then connect the digital output from the Edirol to a minidisc recorder. This makes it for a very efficient and quality recording system which is also portable.
Now, I don't see the point of having to carry a laptop to power up the Edirol alone - the usb battery pack is much smaller/lighter than a laptop but it doesn't work on the Edirol nor in any Type B Usb devices.
As I've mentioned already - it seems to me there are clever marketing plots to make us buying more things than necessary - the Edirol in question would make a great mixing/effects portable device even without any PC or laptop....it's frustrating.

The USB battery pack is a Tecknet iEP380 - 5000mAh with 2 outputs: 5.3v 1A and 5.3v 500mA....so plenty of juice for the Edirol (and the minidisc too - though the latter has already a very efficient battery).
 
But, don't you see, that's all this unit is, Pre amps, switches and potentiometers. It seems the PC is what does the processing. All I can suggest is to contact the makers and ask if this is possible. If you like, I will do it for you tomorrow if you don't have the time.

A Busker with a laptop wouldn't have one for very long lol, so I can see where you are coming from buddy.

Dan.
 
But, don't you see, that's all this unit is, Pre amps, switches and potentiometers. It seems the PC is what does the processing. All I can suggest is to contact the makers and ask if this is possible. If you like, I will do it for you tomorrow if you don't have the time.

A Busker with a laptop wouldn't have one for very long lol, so I can see where you are coming from buddy.

Dan.

this unit costs £199 new....surely it isn't just a bunch of pre-amps, switches and potentiometers...I've just opened and I can see many microchips including a bigger one "Boss" with 30 odd connections on each of the 4 sides - that looks processing stuff to me - no need for a PC or laptop - when I connect it to a PC there is nothing there like drivers running for this unit....I just plug it and the Edirol turns all the bright leds on (after a few seconds - here there might be a clue....) then I plug the mic and headphones and everything works including FX, Phantom power etc. the PC is only supplying the power. I disconnect the USB from the PC and plug it in a USB battery pack and nothing happens!
I think there is a check from the DATA connectors which act as lock (grrrrrrr).

agree...busking is a too risky a business to get your laptop on sight in the street.
 
Or 'plug and play' in a 'handshake' being detected? You are paying for the software too as a package. £100 for a cd with a program on it? If you see where I am going.. How much does a 'raspberry pi' cost nowadays ?

http://uk.rs-online.com/web/p/produ...-3633baf8113b&istItemId=xwipqipxl&istBid=tzit

£20. That might just be an answer..

I see...a teeny weeny computer which does all the basics (including handshake) - not ideal (I'm sure there is a neater solution) but worth trying...I've set my eyes on a few ebay offers and maybe I'll get a very cheap one...it might work. Put a raspberry between the usb battery pack and the USB Type B connector and job done?!
This is inspiring anyhow...there are other stuff one can put in between the USB battery pack the the USB device using type B connectors - USB hubs for example...some are passive but other are active.
 
I think that if the UA-4FX was designed to be used as a stand-alone product then there's be a power input socket. A company such as Roland isn't going to leave out such an important socket. So my read is that this device requires the backbone of a PC to do some of the calculation work.

Roland has stand-alone products with A/D and D/A conversion. I came across the UA-101 as an example. It's about £350. There's your difference.
 
I think that if the UA-4FX was designed to be used as a stand-alone product then there's be a power input socket. A company such as Roland isn't going to leave out such an important socket. So my read is that this device requires the backbone of a PC to do some of the calculation work.

Roland has stand-alone products with A/D and D/A conversion. I came across the UA-101 as an example. It's about £350. There's your difference.

First of all....your idea that the Edirol needs a PC/laptop to "think" is wrong - I've plugged a "very dumb" Fostex MR8 which has a USB host port (to connect a CD writer) and the Edirol turned on and worked perfectly...(case closed).
Second point:
Some functions in certain electronic devices are deliberately hidden by means of firmware - two similar products from the same manufacturer might be exactly the same inside while packaged and marketed to different target customers - why? Because it makes good economies of scale - (I might provide a specific example).
Of course the Edirol case is different but the above should give us an idea of how marketing works - often against the customers' interest (and for better profits for the manufacturer) - this might also be seen as unethical as it produce lot of wastages.
Anyone who doesn't think so...is either too naive (sorry) - or is someone from the other side - i.e. someone who has some links and interests in not telling the rest of us the truth....(case closed).
Next point:
I'll try to power up the Edirol via the Raspberry or via an USB otg connection (e.g. via my smartphone). I've also contacted Roland/Edirol (that's going to be interesting).
 
First of all....your idea that the Edirol needs a PC/laptop to "think" is wrong - I've plugged a "very dumb" Fostex MR8 which has a USB host port (to connect a CD writer) and the Edirol turned on and worked perfectly...(case closed).
Well I think this is the first time you mentioned the Fostex isn't it? If the EDIROL needed just power then it would have worked with the battery pack. USB only has 4 wires. Two for power and the two for data (TX/RX) so I'd say the case isn't closed at all.
Second point:
Some functions in certain electronic devices are deliberately hidden <snip> for better profits for the manufacturer <snip> this might also be seen as unethical as it produce lot of wastages. <snip>
Anyone who doesn't think so...is either too naive (sorry) - or is someone from the other side - i.e. someone who has some links and interests in not telling the rest of us the truth....(case closed)
You seem to have a bit of a problem with businesses making a profit?!? If they didn't make a profit then most wouldn't be in business for very long.

As for features being locked or disabled, yes that does go on. I'm also sure it contributes to profitability, or at least makes lines viable in an ever more competitive market. Its done to rationalise parts inventory; and to make manufacturing leaner to reduce cost and waste; and to make products at lower prices.
 
It just needs a host controller to take it out of a power saving state.

USB OTG with a phone will probably work fine.
 
The pi might be a cheaper option than a mobile. Apart from that, I can't offer any more. You won't get this to work by itself, and for that Reason,

I'm Ooot.
 

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