flyfisher

Could be a switchcraft part: [url="http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=6287023"]http://uk.rs-online.com/web/search/searchB...t&R=6287023[/url]

Just a quick update. I was curious about amplifier efficiencies as discussed above so I bought one of theose Maplin 'energy meter' thingies at the weekend and tried it out with my Ashdown Mag300 Evo II head. I was only testing it at home and couldn't really run it at full volume without shaking stuff off the shelves. I was running it at about half volume, which would be easily loud enough for some outdoor busking, probably too lound actually. Anyway, the meter indicated a maximum power consumption of 143 watts, which was lower than I expected. Not sure if that helps the OP directly but, for anyone thinking of a 'mobile' solution, I'd certainly recommend one of those 'energy meters' as a quick way to get some real figures for their amplifier instead of just guessing.

I wish manufacturers didn't use jacks for speaker connections; it's too easy to use the wrong sort of cables.

[quote name='bubinga5' post='891109' date='Jul 10 2010, 09:53 AM']Music is worth what you think it is...i get no impression from a free CD..i think for myself and listen to the music for what it is, not because its free...[/quote] I wasn't suggesting that the sale price of music correlates to its perceived quality. That's clearly a subjective judgement. I was referring to the mixed messages from the music industry that copying music is theft while at the same time giving away CDs for free. It's like trying to stop people 'stealing' free newspapers from the corner shop.

The trend of giving away free CDs (and DVDs) with newspapers must surely help to devalue music (and films) in the mind of the general public. It doesn't really matter what financial arragements have been made between the record company and the newspaper, the end result is a free CD to the general public, so the impression is that music is not worth much if they can give it away for nothing. On that basis, people might as well download music for nothing as well. I'm in no way condoning copyright theft, but there are some mixed and confusing messages being sent out by the music industry. Probably another example of how they don't really know how to deal with the digital world.

Hey, where did you get that photo of my bass I made this afternoon?

I reckon I could knock out a bass from scratch in an afternoon and it would be both rare and unique. It would also be crap.

Almost there. As you say, ignoring efficiencies, you're looking to draw 600W. From a 12v battery that will mean 600 / 12 = 50A. If you draw 50A for 4 hours that's 50 x 4 = 200 Ah. That's quite a lot of power, even for a car battery. However, as previously pointed out, you're unlikely to be running everything a full whack, especially (I'd guess) a 500W PA. We can guess about amplifier efficiencies but actual volume will likely be the biggest variable. If you're seriously considering a totally portable set-up then it would probably be worthwhile to get hold of a power consumption meter (I just checked and didn't realise they are so cheap these days: [url="http://www.maplin.co.uk/Module.aspx?ModuleNo=286534)"]http://www.maplin.co.uk/Module.aspx?ModuleNo=286534)[/url] and then measure your actual consumption at practical volume levels during your next rehearsal. Then plug the measured power figure into the above calcs. I'm a bit out of touch with inverter efficiencies, but I reckon 80% would be a conservative figure. If you still find you're short of power then a second battery might be an option and would double the capacity at a stroke, although you'd need a 24v inverter rather than the more commonly used 12v types plus, of course, another heavy battery to lug around. You mentioned marine batteries; as I understand it, most of these are specifically designed for 'deep discharge' applications, i.e. where the battery is regularly discharged of almost all its capacity. This is an important consideration because most car batteries don't like being fully discharged and it can seriously shorten their useful life.

[quote name='Phil Starr' post='886841' date='Jul 5 2010, 11:18 PM']I think people are being a bit pessimistic about the inverter. The guy who did the calculations is probably pretty close ( i can't fault his reasoning) but remember you are not playing full volume continuously, there are loud and quiet bits. My 20W Peavey practice amp almost matches a drumkit when we practice in an enclosed practice space and even, say, 5W will be louder than an acoustic bass and more than match an acoustic guitar. If you turn it down it should give you a lot more battery life and are you really going to play longer than a two hour set. I'd try it and if it runs flat too quickly you can always connect it to a car battery for more life.[/quote] I'd go along with all that. Indeed, that's why I chose the 10W amp to illustrate the issues rather than the larger 20W option. But my real point was to show how these sorts of things can be worked out rather than just guessed at. Maplins sell plug-in power meters, which could be used to measure the actual power consumption of the proposed amplifier and this would then enable a more accurate calculation of the likely playing time. But the bottom line is always going to be the basic battery capacity and, in general, the smaller, lighter and cheaper the device in question, the less power it will be able to dispense. Personally, I'd favour a car battery on a small luggage trolly - preferably one of those fully sealed ones that don't spill battery acid.

Fair enough. I've never tried one, although I've often thought about one for practice purposes.

If everyone else is acoustic, would an acoustic bass be an option? Still not zero budget though, unless you could borrow one.

[quote name='d-basser' post='885795' date='Jul 4 2010, 08:53 PM']are there better options?[/quote] An extension mains lead and friendly shopkeepers? Or a car battery on a small luggage trolly with a separate inverter? Power is power, I'm afraid - you can convert it but you can't conjure it up out of thin air.

The clue is in the battery spec of the unit, which was stated as being 2 x 6v 5Ah batteries. That makes 12 volts at 5Ah, which basically means they can supply 60W for one hour. But the inverter (to boost the voltage to 220Vac) won't be 100% efficient so that will consume some of that power itself. If we assume 80% efficiency, we get a figure of 48W for one hour. I don't know the efficiency of a small bass amp, but let's assume 50%, meaning that a 10W amplifier will draw 20W of power. So the unit should power your 10W amplifier for 48/20 = 2.4 hours. If you try to draw more than 200W from the unit then the inverter will either go into self-protection mode (or just go bust!), but even when right on the limit it can only supply 200W for about 15 minutes with the specified batteries. All these figures are approximate though and will depend a lot on the condition of the batteries and the efficiency assumptions, but they should give you a rough idea.

I've always found The Faces to be wonderfully 'loose' (not sure what the correct term is), almost as if they are all just playing their own stuff solo but yet it all seems to magically come together for a great sound. Our band is much the same really. Except for that last bit.

[quote name='skankdelvar' post='885201' date='Jul 4 2010, 02:15 AM']Ultimately, it's matter of preference and financial resources.[/quote] Isn't that a universal truth? [quote name='BigRedX' post='885202' date='Jul 4 2010, 09:18 AM']BTW it doesn't matter which Fender you buy they all suffer from the same fundamental design flaws, which makes where they were made irrelevant.[/quote] Wouldn't 'fundamental design flaws' make any product effectively useless? I appreciate you might not like Fenders (as per skankdelvar's observation) but their widespread use througout the professional music industry would seem to suggest they are far from useless.

I'm sure a lot of it is peer-pressure and self-esteem. Look at clothing, cars, hi-fi, laptops and mobile phones - they all have their 'cool' brands and people end up paying for it, presumably to make themselves feel good and/or superior. The extreme of this sort of behaviour is epitomised by personal number plates - what function do they serve except to broadcast to the world that the owner has money to burn? The implication, presumably, being they are therefore somehow superior to everyone else. Sure, there's an element of getting what you pay for, but get beyond the level of adequate functionality and build quality and you're into paying-for-the-image territory.

Ignoring the apparent controversy about water possibly damaging the electronics, how much water would actually get into that area anyway? I can't imagine any water getting through the scratchplate and the pots are well sealed under the scratchplate by their locking nuts. The jack socket also wouldn't let in much water if a lead was plugged into it. So, given that the bass is only going to be splashed with water, not immersed into a bath full of the stuff, I can't really see the electronics coming to much harm.

[quote name='RAY AGAINST THE MACHINE' post='883446' date='Jul 1 2010, 09:40 PM']You always think 'but I may need them incase ''[/quote] How did you know I always think that? I've got a box full of them, but then I rarely throw anything away. I'm sure I've read somewhere about an initiative to standardise low-voltage dc connectors so we could have a single 'universal' 'power brick', but I've seen no real sign of them. USB connectors are increasingly used for power but really the whole area is a right old mess. Still, it keeps the PSU manufacturers in business.

[quote name='chrisba' post='877352' date='Jun 25 2010, 01:20 PM']I asked Ashdown the same question regarding my Electric Blue combo. They replied that it could damage the amp, so don't do it. This is not true of their more expensive amps.[/quote] I've got an Ashdown Mag Evo II with a DI output, so I checked the manual but it said nothing about phantom powering. I emailed Ashdown asking them if connection to a phantom powered input could damage the amp and received the following reply: [i]The DI output is indeed protected against phantom powering… It incorporated blocking capacitors in each line.[/i] Frankly, I'd have been surprised if the DI output wasn't protected against phantom powering; (a) it's trivially simple and cheap, ('b) it's good design practice to protect any input/output against reasonable abuse and external faults. Pity they didn't spell it out in the manual though.

All sorts here: [url="http://www.machinemart.co.uk/shop/categories/search/fans-air-conditioners--ventilation"]http://www.machinemart.co.uk/shop/categori...rs--ventilation[/url]

[quote name='Alien' post='880545' date='Jun 29 2010, 12:22 AM']but nobody bats an eyelid about the stresses on those solder joints do they?[/quote] Perhaps they should. A heavy cable is just as susceptible to movement and vibration as anything else and should ideally be mechanically fixed rather than just soldered and allowed to flap around. How many people have experienced "socket" problems at some time or another? These are the sorts of construction details that can determine long-term reliability.

+1 to all that. Solder joints are for electrical connectivity, not for securing large components in a highly vibrating environment. Better safe than sorry.

Happy, happy days.

My cabs have jacks and speakons but I use speakon connectors for the good reasons above plus to avoid getting the speaker cables (which should be heavier) mixed up with signal cables.

Thanks for the youtube link. Wonderful stuff. Great songwriter. I must be getting soft in my old age, I seem to have a bit of grit in my eye . . .