Mottlefeeder

[quote name='mcnach' timestamp='1386555312' post='2301480'] Last summer I needed something portable for busking and I ended up with a battery operated "miniPA system". It cost me under £150 and it worked beautifully. I never needed to crank it above 11am or so (if you imagine a clock face on the volume knob). You can find more info on this thread: [url="http://basschat.co.uk/topic/212137-portable-solution-for-busking-on-bass-new-amp-or-batteryinverter/"]http://basschat.co.u...atteryinverter/[/url] [/quote] Thanks - I remember reading this and another thread earlier in the year. I'm aiming more for a hand-carry system - The pubs I go to are old Victorian ones, with steps up to the door, which opens outwards. Getting in with a bass on my back is bad enough, but a bass and a trolley and steps is something I am trying to avoid. Also, to take up less space in the pub, I would prefer a rig that I can sit on. David

[quote name='MoonBassAlpha' timestamp='1386321203' post='2298628'] Don't forget, the car audio amp will expect to be fed with line level input, so you'll need a preamp to get the power out, and you don't need 300W of bass power to beat off 10 acoustic guitars, a Cube 30 or similar would be more than adequate. [/quote] I've heard a bass player using a passive Squire P and Peavey Microbass in this situation, and it was distorting as it struggled to keep up, which makes me wonder whether 30W will be enough - I agree with you that 300 watts would be overkill: that was a rig I used for an outdoor event. I already have a Hartke Kickback 10, and that works for me, but takes up more space than I would like. My aim is to use a speaker cab that is the right height to sit on, so that I do not take up any more space than the other players - that tends to limit the number of combos I can consider. My main interest in car amplifiers is that they are readily available, cheaply, second hand, so I can dabble and sell on if it does not work. Their sensitivities tend to be variable from 200mV up to 4V, so an active bass may be able to drive them with no further boost. David

[quote name='Dad3353' timestamp='1386291148' post='2298516'] DC watts, for our purposes, may be considered to be V x A. A 12v battery, delivering 100W, has 8A being drawn. Pro rata, 300W draws 24A etc. A battery with a capacity of 10A/H may deliver 100W for about an hour or so. At 300W it'll run out after approx 15-20 minutes. Hope this helps. [/quote] Thanks for your input - I agree with the theory, but the rig will not be delivering continuous power. There is an article on the EBS site about power requirements for bass amplifiers which states that the ratio between the peak signal of a plucked string and the average of the note is about 12:1, so you need the 100W for the first few vibrations of the string, and much less for the rest. My approximate measurements of average current drawn are in the same ballpark as the EBS figures, and show the audio power taking about 2 amps at 12V, and the losses for the invertor, power transformer, preamp, etc taking about 1.5A at 12V. Cutting down on the losses would make a big difference to how long the battery will last. David

[quote name='MoonBassAlpha' timestamp='1386265302' post='2298002'] how about the E H 44 Magnum, runs off 24V 2A? 2 old Bike Batteries would do the trick, I would imagine. I always thought it would be a good idea to try a small class D amp off a couple of cordless drill battery packs [/quote] A possibility, but quite low powered and expensive compared to dedicated auto designs. On the subject of batteries, car and bike batteries are designed to run almost fully charged all the time, and do not take kindly to being fully discharged. For this kind of application I would need a golf cart battery or something similar. David

[quote name='Thunderbird' timestamp='1386185865' post='2296938'] I may have missed the point but wouldnt it be easier to run a small combo to do this? certainly alot less to lug around [/quote] The acoustic sessions I attend, and the outdoor gigs I plan to attend, may not give me easy/any access to a 240v supply, so a combo on its own is not the optimal solution. In pubs without a performance area, they tend to have one socket for the vacuum cleaner, and one for the fruit machine, and sods law states that neither of them are anywhere near where you need them. The combo I have is a 1 x 10, and weighs 15kg. Carrying it more than 100 yards needs a trolley, so it is feasible to put a caravan battery and an invertor on the same trolley, but a 4kg battery and a 2kg amp would fit in a rucsak and a neo-loaded speaker cab and bass could be carried by hand, which would be a much easier option. A PJ Briefcase with battery would be heavier and only lasts one hour. David

I'm starting to put together a battery powered rig, which has to be loud enough to be heard with about 10 acoustic guitars in a pub, or busking outdoors. One option is to use existing amplifiers and speakers and an invertor and 12 volt battery, but the other option is to use a bridged car stereo amp with a battery. I have previously run a 300W Hartke head into a 1*15 Hartke cab using a 300W invertor with a caravan battery, but the standing current is about 1.5 Amps and at normal playing volumes, the battery is delivering an average of about 3.5 Amps. Car audio amplifiers have a standing current of about 0.5 Amps, so the battery could be smaller and lighter. To give me about 100W RMS into 8 ohms, I need something like 2 * 50W RMS into 4 ohms, which translates into an amplifier marketed as 300W to 500W depending on the manufacturer. I'm think of the brands Kenwood, Alpine & JBL as being fairly good, but I have no feel for the other brands at the budget end of the market - FLI, Edge, Juice etc. Can anyone advise me on the brands to avoid/consider for this project? Thanks David

The problem may be more to do with European Directives about safety than about the electrical limits of the plug and socket. Exposed live terminals with more than 50v on them are a shock risk, and if you are hot and sweaty, the shock will be worse. It will not kill you, but could cause you to fall off stage, etc. Speakons are designed so that you cannot accidentally touch the live connection - jacks are not. Back in the day, some amps used XLRs to connect the speakers, and mains XLRs for the 240v supply. The clearance between terminals and metal shell does not meet current safety standards, so mains XLRs have gone, and XLR are limited to lower voltages. David

[quote name='rhythmbug' timestamp='1382365548' post='2251221'] Stumbled across this thread while looking for solutions for the neck dive on my Corvette. Seller no longer appears to have anything for sale. Any idea who else might sell this strap, or a good alternative? [/quote] I tried several methods with my 5-string Corvette: 1) I drilled a deep hole and fitted a threaded insert in the end of the horn. I was then able to fit a threaded rod into the horn, so that the sides of the hole supported the rod, and the threaded insert kept it in place. You need to extend the horn by about 1 1/2 inches to get the bass to balance, and it looks odd. 2) I poured nuts and washers into a padded phone case and hung it on the body end of the strap - from memory, you need about 12 oz of extra weight (hanging on your shoulder). 3) I bought five Hipshot Ultralites and fitted them - they helped but were not enough. 4) I lined the control cavity with a piece of lead of the same depth as the cavity - it helped, but was not enough. They all have an effect, but you end up with an instrument that is heavier, looks wrong, or is considrably more expensive that what you wanted to own in the first place. I sold mine on. David

I recently heard a double bill of two folk bands. One used an ABG which fitted in well acoustically, and the other a P bass, which did not. Whether the latter was due to his EQ and style I'm not sure, but it really did sound wrong to me. David

I've just started converting '60s & '70s vinyl 'Greatest hits of...' to CD to MP3 so I can learn the bass lines for a pub jam session - early Stones, Who etc. Should have done it years ago - stuff I enjoyed listening to, but never learned to play. David

For anyone who is gassing for a 5-string TRB, may I remind you that my fretless TRB1005 is up for sale [url="http://basschat.co.uk/topic/206380-for-sale-yamaha-trb1005-fretless-now-l425/page__fromsearch__1"]http://basschat.co.u...__fromsearch__1[/url] Here's a taster David [url="http://s285.photobucket.com/user/Mottlefeeder/media/DSCF0539_zps2ffc5e1a.jpg.html"][/url]

I've just had a look at the Fender Passport mini, and it comes without batteries. It takes 6 'C' type cells which will set you back about £12-15 per set of alkalines, or £20-25 for a set of rechargeables. Add to that the cost of a new charger, if you do not already have one that takes that battery size, and you are in the same ball park as the cost of replacing your existing power pack, which will also run your amp more than twice as long - and you still have to buy the Fender kit. That one-box solution seems an expensive way to go. David

[quote name='Jonnyboy Rotten' timestamp='1378401114' post='2199810']... I tried the battery pack for a while but the missus thought it would be a good idea to plug her hair straighteners into it while camping and I think she blew it - it can't even cope with a mobile phone being plugged into it now! ... [/quote] When I plugged a 900w power drill into my 300w invertor, it ran for a few seconds and then blew the incoming fuse. If you haven't already checked, that may be all that is wrong with yours. I have no experience of the passport mini. David

A bit late to the party, but still may be able to help... +1 for PU, and mentioned by flyfisher Polyurethene glue foams and expands as it goes off, so it will force itself at least part way into the join, and it provides a bond that is usually stronger than the wood. I'd wipe the joint area with a slightly damp cloth, to make sure the glue starts to cure then run a fillet of PU glue down it. David

[quote name='GregBass' timestamp='1377698661' post='2190512'] If you have sound on your PC, Maplin sell USB turntables. You can then use your existing gear [/quote] If you check the 'Which' reviews at your local library, some of these basic USB turntables provide a really low-quality output. David

I have a related but slighty different question - I'm thinking of frettting a fretless that was supplied with brass 'fret' markers. Any thoughs on the best way to get the markers out? I am assuming that the brass would be harder than the rosewood of the fretboard, so a saw would wander. and I do not think I can use a soldering iron to expnd the metal to widen the groove so that it can be got out more easily - it would burn the wood. The only thing I have come up with so far is to grind down a Stanley knife blade and use that with a hammer to tap out each fret marker. A ground-down single-sided razor blade might be better, but I am not sure if you can still get them. Any comments welcomed. David