flyfisher

[quote name='observer' timestamp='1322845136' post='1456634'] Any advantage/disadvantage of wiring drivers in serial or paralel mode? [/quote] If you wire in parallel then failure of one speaker won't mean failure of the whole cab but if in series failure of one speaker would silence the other one. But other than that I don't think there's a lot of difference. The above-mentioned issue of matching the speakers to the cab is the trickiest issue.

So, I go out for the afternoon and come back to find padlocks all over the place. Clearly BC can't be too boring then.

According to this, the Sound Destruction Device runs off a 9 volt battery: http://graigmarkelmusic.com/Graig_Markel_Music/Sound_Destruction_Device.html That suggests to me that the external power supply is regulated down inside the unit. Most voltage regulators only need a couple of volts of 'headroom' to be effective so it might be that a 12 volt PSU would work. It certainly wouldn't hurt to try if you have one handy, but if you're buying a new one then you might aas well use get one with the specified voltage. I couldn't determine the exact PSU connector type from this info so my previous suggestions stand. Though it might be worth sending an email to the company to ask them for the precise connector type. Good luck with it though, looks like a great toy!

'negative tip' refers to the wiring of the connector that plugs into your gadget. Unfortunately there's no official standard so they can be wired either way. A photo would help to identify the exact type of connector you need but meanwhile I'm guessing it's a 'barrel jack' like those shown in this link: http://www.maplin.co.uk/dc-power-plugs-43084 Unfortunately, they come in a couple of diameters and differing lengths. If you can take your gadget along to somewhere like Maplins then they should be able to tell you exactly what connector you need. Alternatively, you could buy something like this: http://www.maplin.co.uk/ac-dc-multi-voltage-4a-switched-mode-power-supply-48517. It's far more power than you actually need but it's a pretty good price and one of the supplied connectors will probably fit - assuming you really need a barrel-jack of course. With a bit more searching you should be able to find a cheaper 15v/1000mA, though you'll have to be sure of the exact connector type.

I play with two bands but we only do about 10 gigs each per year and there haven't been any clashes yet so it's no big deal. Obviously it must get more difficult to schedule things with more bands and more gigs but, ultimately, it's no more difficult than juggling all our other commitments such as family occasions, holidays etc. Just keep a diary and deal with things on a first-come-first-served basis. if a clash can be worked around then fine but if it can't then the first commitment takes priority - just like all the other demands on our time really. Anything else and you're breaking commitments somewhere and will become known for being unreliable.

Good stuff. Sounds like the job's almost done - nice one. I just hope 1 amp is sufficient!

To avoid having to bother with making up the molex connectors, you could try buying a hard drive power cable splitter that has the molex connectors already fitted. A bit like this one: http://www.amazon.co.uk/gp/product/B000ITL4KI/ref=pd_lpo_k2_dp_sr_1?pf_rd_p=103612307&pf_rd_s=lpo-top-stripe&pf_rd_t=201&pf_rd_i=B0014BL9PE&pf_rd_m=A3P5ROKL5A1OLE&pf_rd_r=1EJ3BPVWAJHMZ58P3SMZ Any local PC shop should have something similar. Then just cut off the unwanted connector and wire it directly to the screw terminals on the PSU, leaving the two others to connect to the Joe Meek units.

Something like this? http://www.sim-entry.com/12V_1A_power_supply/p163033_2132065.aspx Assuming 1A is adequate of course.

I wouldn't bother about building a PSU. It's not that difficult if you know what you're doing but it's a safety-critical item so the risk is not worthwhile, especially considering how cheap a fully-approved PSU is to buy. Whatever you decide to do, you [u]must[/u] know the power requirements of the PSU if you're to avoid under-spec'ing the PSU so that it runs hot or shuts down, or fails. You also don't want to over-spec the PSU because that will just waste money. The Joe Meek units must surely have a specification somewhere that will tell you their power requirements? If you really can't find the info and you don't have any other high-powered PSUs you could hook them up to a car battery (via the cigarette lighter) and measure their power consumption with a meter. Once you have the power requirements it should be easy to find a suitable PSU to buy, especially for something so standard as 12 volts. Then your only problem is to fit the required molex connectors. These are easy as long as you have the right sort of crimping tool. Don't be tempted to use pliers unless you want a bodge that won't give a reliable connection. Maplin will probably have the parts you need or an online supplier like CPC. If you rarely do this sort of thing then you probably won't want to be buying special tools and test equipment so the best bet would be to try and find someone local who could help. A local guitar/amp tech would be a good place to start.

I'd say that, barring any unfortunate defects, we're all born pretty much equal. However, our environment and experiences start to influence us from the moment we're born (possibly earlier). We may be born with physical attributes that help us achieve more than others in certain chosen fields, but I'm not sure I'd call that 'talent' as such. To paraphrase Arnold Palmer (I think it was), life is purely a matter of luck, but the harder we work at something the luckier we're likely to be.

Fair point ped, but I think I know what Pete means - I guess it's the difference between a real community or just another specialist forum.

[quote name='Rumple' timestamp='1321969922' post='1444904'] I'm shocked only 160 people have voted out of nearly 19,000 members. [/quote] I'd bet that a large proportion of those 19,000 members are long gone. it would be interested to see a breakdown of membership based on when they last logged on or their login frequency, e.g. # members who logged on in last week # members who logged on in last month # members who logged on in last quarter # members who logged on in last year # members who have only ever logged in once or twice (i.e. signed up, asked one question, then never returned).

Interesting comments about Audacity stability - I've always found it to be rock-solid, though I generally only use it for wav editing and recording from YouTube. For music recording, I've been using the freeware Kristal Audio Engine (http://www.kreatives.org/kristal/). Probably not the best available but I've found it very easy to learn, possibly because it doesn't have every bell and whistle that the high-end DAWs offer.

909 is on our covers set list and that's nothing like the original bass line - which is not necessarily a bad thing of course, but I'm just saying. [media]http://www.youtube.com/watch?v=_D74rJzHFdg[/media]

[quote name='Ou7shined' timestamp='1321700463' post='1442066'] I voted to keep the "likes"... because it's nice to be nice. [/quote] While I agree with the sentiment, a 'like' button need not be used in a nice way. Consider an abusive/racist/sexist/whatever-ist post - that could be 'liked' couldn't it? Without knowing the motive behind like/dislike voting, it's all a bit meaningless.

[quote name='Kiwi' timestamp='1321658065' post='1441831'] Already we know of one member (not a mod) who created a separate profile so they could like their own posts under the other profile and then asked why we were taking issue with their posts when they were liked so many times...but my lips will remain sealed...they know who they are. [/quote] Oh dear. Some serious personal issues there. As I mentioned previously, I can't really see the value in the reputation system because the basis for people's likeing/disliking can never be known unless they post their reasons, in which case there's no need for the system in the first place. But I'm not voting in this poll because I don't really care if the system is in place or not so it seem unreasonable for me to force my opinion on anyone else that does (or doesn't) want it. What ever happens, I'm not likely to use it and I'm not likely to change my opinons or behaviour because of a set of ill-defined 'scores' - though a good well-argued debate is likely to be far more influential.

[quote name='andrewrx7' timestamp='1321451224' post='1439277'] Thanks. I get the principle of overall load on the amp, I believe mine is min load of 4ohms. I also think it is a mono amp. I wasn't sure that if you linked a 2nd cab to the first one (daisy chaining?) the load rating would follow the same rule as if you connected 2 cabs separately to the amp. From what you are suggesting, linking the cabs together is still wired in parallel, so with 2x 8ohm cabs daisy-chained the load on the amp is still 4ohm, and is just fed via one of the outputs. I guess this is not recommended since more current has to flow down the single connecting cable rather than splitting the current into two cables. [/quote] Yep, you've got it. You're also correct that a daisy-chained arrangement will mean more current flowing down the single connecting cable but in practice this is not a problem if you're using a good quality cable. There is another practical consideration of such an arrangement in that if the amp speaker cable develops a fault then both cabs are affected, whereas with two separate cables they would both have to fail before things went quiet. But again, in practice it's not a big issue. [quote name='andrewrx7' timestamp='1321451224' post='1439277'] I'm sure I read somewhere, that cabs can also be wired such that the linking of two together is in series and not a parallel. How would you know? There is nothing on the cabs to state what kind of wiring has been used for the link socket. [/quote] It's certainly possible but not very common in my experience. As mentioned, you'd need special cables or adapters for such a configuration.

[quote name='RhysP' timestamp='1321451613' post='1439288'] The combos do too. I can power my Zon fretless & Bogart five string from my Gorm combo using a stereo lead. Unfortunately I can't do it with my other Zon as it's 18V. [/quote] I've really surprised these things have not been standardised as they have with 48v phantom powering of microphones. 48V should be quite adequate for powering all manner of active electronics inside a guitar.

[quote name='xgsjx' timestamp='1321462358' post='1439467'] Edited to say, I can't help but giggle at the expressions on their faces! [/quote] That's because those headsets are the latest technology for 'adult telepresence services'

[quote name='monkeynuts' timestamp='1321456615' post='1439391'] Yea i'm not sure what it's like getting out of the car park but for the last few big ones they have done there they have closed that junction of the A1 and dedicated a lane just for traffic in and out. So once you get out of the car park there hasn't been any major traffic issues. [/quote] I should clarify my '5 hours' story to confirm that was the time it took us to get [u]out[/u] of Knebworth park! The A1 itself was fine because, as you rightly say, the traffic management at that point was pretty good. I think the basic problems is that people tend to arrive over a period of many hours but that they (mostly) all try to leave at once. In our case, parking was in various fields and I assume they let them empty one at a time because I remember not moving at all for hours at a time - literally not moving, not even crawling along. I guess it was just the luck of the draw where we found ourselves parked up when we arrived. Walking to Stevenage only takes about 20-25 minutes, which puts it into context. But, I hasten to add that was back in 1986 so they might be better organised these days.

[quote name='Mr. Foxen' timestamp='1321442377' post='1439082'] Problem is, when mixing cabs, that one could be much louder and handle more power than the other, and drown out the noise of the other one being upset. [/quote] [quote name='xgsjx' timestamp='1321443904' post='1439117'] & that's why you're usually better having 2 of the same cab. [/quote] Yep, both good points, but the (potential) different loudness of different cabs is due to different sensitivity/efficiency of the cabs rather than their power handling as such. A 400W cab won't necessarily be louder than a 200W cab. Just clarifying the point, because the OP only mentioned ohms and power ratings. Sensitivity is an additional consideration.

There's no fundamental limit on the number of speakers that can be connected to an amp. Think of 1x15, 2x10, 4x10, 8x10 cabs - they've each got a different number of speakers in them but will work perfectly well because the speakers within the cabs have been chosen and connected such that they present an overall 8 or 4 (or whatever) load to the amp. It also doesn't matter how many speaker outputs an amp has - it can still be connected to any number of cabs/speakers as long as the overal load is within the spec for the amp. Having said that, in practice cabs are usually 4 or 8 ohms, amps often have two outputs and cabs also often have two connectors - all of which makes things easier when connecting stuff together. An amp with two outputs can be connected to two cabs, one output to each cab. But it can also be connected to just one of the cabs and a 'link' cable can be used to connect that cab to another cab. Electrically, the two methods of connection are identical - the two cabs are connected in parallel to the amp (note that this only applies to a mono amp - a stereo amp with two outputs is, of course, really just two amps with one output each).

I've been to knebworth twice. First time it took 5 hours to get out of the car park, so you might want to consider just sleeping in the car! Second time, we parked somewhere in Stevenage and walked the mile or so to the park. That was a long time ago though.

[quote name='andrewrx7' timestamp='1321440532' post='1439051'] 1. Basic power ratings between an amp head and cabinets – if I hooked up a 200w cab to a 300w (or higher) head, is there a risk of doing damage to either the speakers or the head? (this is assuming the input gain is set correctly and not being clipped). Would I be correct to assume this is OK, since the head is rated at 300w @ 4ohm, but will be around half that with 1 cab attached, which is rated to 8 Ohm, so the amp is able to supply around 150w to a single cab? [/quote] The general view is that a speaker that's driven with a potentially damaging level of power will sound bad before any actual damage is done. So that's a good starting point - if things sound good then they're almost certainly 'safe'. For your specific example, a 300W @4 ohm amp will deliver a bit over half that at 8 ohms. I tend to use 2/3rds as a rough guide, which means about 200W at 8 ohms in this example. Thus a 200W 8 ohm cab should be fine, even at the full output of the amp - but again, let your ears be the final judge. [quote name='andrewrx7' timestamp='1321440532' post='1439051'] 2. What is the effect of putting two cabs that do not have similar power ratings into the head? For example, the 300w head @ 4ohm, will take 2x 8ohm cabs. But one cab is rated to 400w, while the 2[sup]nd[/sup] cab is 200w. So impedance is correct, but what effect does the different power ratings have? [/quote] The power rating of speakers does not affect [u]where [/u]the power is dissipated, only whether the speaker can handle the power that [u]will [/u]be dissipated. It's the impedance that will determine where the power is dissipated. Thus, in this example, two 8 ohms speakers (in parallel) will present a 4 ohms load to the amp. The 300W at 4 ohms amp wll therefore deliver 300W and because both speakers have the same impedance the power will be divided equally between them. Thus each speaker will be driven with 150W, which is comfortably within the rating of either speaker.

You couldn't make it up make it up . . . . er, except they do. Right out of thin air. Still, Odin is a good name - it's all mythology after all. I bet they're ROTFLTAO everytime they get an order. Harry Enfield could have made it into a sketch . . . . [media]http://www.youtube.com/watch?v=uVvcD4Czx4Y[/media]