bumnote

[quote name='Phil Starr' post='1069397' date='Dec 25 2010, 11:30 PM']By the way it is the area that determines sound output ,all else being equal, so one 15 = about 3.5 10's[/quote]

could you explain a bit further? i know the moving part of the speaker isnt actually 15" but if the area of a circle is pi r squared then my maths makes a 15 at 176 sq ins and 2 10s at 157.

Ta

I dont know if it will fit a lakie, I have three and all had to be fettled to fit.
The biggest difference is it has 10 screw holes as opposed to the normal 13 on a fender.

Most of them line up but you would have to drill some new holes

Having taken the mick a while back lets be a bit more serious

Why are you retiring the 220, did that normally keep up volume wise? or did you struggle with that.

Legendary though the acoustic amp is, I would be surprised if that would keep up where a mag wouldnt.

If you seriously need to start going out with the mag through the 402 and a stereo amp driving 2 additional 1 x15s, I would question the volume levels you are playing at.

I certainly wouldnt want to carry it all. If your guitards are using 200 w blackstars, I suspect even my 370 would struggle.

I would tend to agree with Umph , you would probably get more sound cheaper by doing something about your existing speakers, but I dont know how efficient the 402 cabinet design is, and the 404 isn't wonderful.

Sorry both lets get the name right

Must be one of the quickest in and outs of all time

[quote name='4-string-thing' post='1057848' date='Dec 13 2010, 09:19 PM']Ok, I've decided to retire my old Acoustic head from gigging, its 30 years old, after all.



Cheers![/quote]


Oh Oh Oh Oh you philistine

Blimey someone got the deal of the month

£200 for the combo is a steal, you would have to pay virtually that for an ABM 300 top

pmed

[quote name='Mickeyboro' post='1054285' date='Dec 10 2010, 05:04 PM']I got a bog standard Samson bug. Does the job, Precision sounds fine.

[url="http://www.samsontech.com/products/productpage.cfm?prodID=145&brandID=1"]http://www.samsontech.com/products/product...5&brandID=1[/url][/quote]


How are you getting on with the Classic Vibe 50s Mick?

The stage clix one looks good but it is recommended for passive basses

Ive got two Samsons but TBH they work, and they are very convenient, no mucking about with a tranny on your strap or in your pocket, but they dont match up in terms of quality to the Line 6 X2 or the relay. Doesnt really notice on stage, but it does at home or in the studio

Personally, if I wanted the best quality I would probably opt for a line 6 relay.

I had a very very competitive quote a few years ago, but dont forget to factor in VAT at 20% including shipping costs, unless you are very quick, and Import Duty


[url="http://www.basscentral.com/lakeland_usa/lakland_494.shtml"]http://www.basscentral.com/lakeland_usa/lakland_494.shtml[/url]

I do prefer the old style music man logo

[quote name='Christophano' post='1052208' date='Dec 8 2010, 10:41 PM']Crikey.... There isnt an impedance changer switch or anything... If such a thing became a problem, how would one change the impedance the amp was chucking out? Knock three times?[/quote]


I dont know your amp well but if you had for example a marshall from that period it would have a plug on the back, which you could change from 15 ohms to 7.5 ohms, depending if you were using 1 cab or two.

With your amp, it was designed as a package, ie the speaker was chosen to match the characteristics of the amp. Actually in those days, it was probably what was available.

There may be different tappings on theoutput transformer to allow you to change, I have no idea.

Much easier is to find accurately the impedance of the original speaker, and get a replacement to that spec, or have the existing one rebuilt which will retain the vintage characteristics.

Phil Star says measuring with a multimeter and multiplying x 1.3 will give you a good idea and he knows far more than i do. Alternatively contact WEM and ask them

This part of an article from sound on sound

Whereas most modern solid-state amplifiers are virtually bombproof in terms of whether their outputs see proper loudspeakers (of any nominal [size=4]impedance) or a short or open circuit, most valve amplifiers are far less tolerant. In fact, the majority of vintage valve amps will self-destruct if driven without the correct speaker load attached! The reasons are complex and depend to some extent on the design of the output circuit, but can be boiled down to what are called 'reflected' impedances.
[/size]
Most, if not all, practical valve amplifiers employ an output transformer. The use of the transformer is principally to translate the effective load impedance between that required by the valves, and that of a practical loudspeaker — a typical valve output circuit requires a load of between 5k(omega) and 10k(omega), whereas a practical loudspeaker presents a nominal impedance of between 4(omega) and 15(omega). The transformer does this by 'reflecting' the loudspeaker's impedance through the transformer (as a function of the square of its turns ratio) to create a different (in this application, higher) load impedance for the valve output stage. Thus a 15(omega) speaker will appear to the output valves as a 9k(omega) load, say. It is important to note that it is the physical loudspeaker's impedance that defines the operating load for the output stage, and that valve amplifiers are very fussy about their load impedance. If a loudspeaker with a different speaker is connected, the output valves will see a different load and their performance and operating characteristics will change as a result.

Consequently, to make the system more flexible in accommodating different loudspeakers, many valve amplifiers have different output terminals (or some way of selecting nominal output impedances) for different loudspeaker loads. This is achieved by using different tappings on the output transformer so that an 8(omega) speaker connected to the correct terminals will produce the same reflected impedance to the output stage as a 15(omega) speaker connected to its appropriate terminals.

So what happens if the loudspeaker is disconnected? Well, instead of the 15(omega) load being reflected into a 9k(omega) load for the valves, we now have an infinite load, which will be reflected as an infinite load to the valves. For a given current, an infinite load requires an infinite voltage. Imagine a brief positive transient audio signal (a drum strike, perhaps) driving the output valves to the unloaded output transformer. When that transient stops, the magnetic field developed in the transformer collapses and generates a reverse polarity signal called the 'back EMF'. With an infinite load impedance, the back EMF will tend towards an infinite reversed voltage spike and this is applied directly to the valve anode plate. Depending on the valve in use, this huge back EMF is likely to far exceed its rated values and so may cause the valve to break down, damaging or destroying the grids or anode plate, and resulting in one very poorly amplifier.

However, this huge back EMF can only be generated if the amplifier is being driven in the first place. If there is no input signal to the amplifier, there will be no output signal, and so no back EMF. Under these rather exceptional circumstances there is unlikely to be any damage. The most sensible thing to do, however, is to always check that a suitable loudspeaker is connected to a valve amplifier (with the correct output terminals or transformer taps selected), before you connect or turn up the input.

[quote name='icastle' post='1051732' date='Dec 8 2010, 02:41 PM']Yep.

Modern 'off the shelf' replacement speakers of the size you are looking for only come in three impedances:
4Ω - well below the minimum impedance of the amp and carries a high risk of damaging it.
8Ω - nearest value to the 6Ω minimum impedance of the amp.
16Ω - would work fine but output would be reduced.[/quote]

Unlike transistor amps, providing the output from the amplifier is set to the impedance value of the speaker, you will get the rated output from the amp, it doesnt matter if its 4, 8, or 16

However, a valve amp must be set to the impedance value of the speaker, otherwise when a signal passes through it there is a real danger of damaging the amplifier.

Therefore 'IF' it is a 6 ohm output and you connect a 15 ohm speaker, you will not get reduced output, you could very well fry the amp.

[quote name='Mr. Foxen' post='1051931' date='Dec 8 2010, 05:39 PM']I was totally confusing with Korea. But the point where Vietnam was fighting, there was a north and south, and the Americans were supposed to be fighting for the not communist half. If they were doing it now, they would call it 'liberating' and 'defending freedom', as they were supposed to be saving the civilians (who work in factories making Nampegs) from the Viet Kong 'insurgents' who were seeking to make them into pinkos. Of course, the Americans lost, so they are pinko commie slaves now.[/quote]


I think my original point was from a marketing point of view it caused some upset from the vets and their families. My Father was a policeman in the second world war, and he refused to allow Japanese goods into the house although he didnt hold the same view about anything German.

Go fi gure

[quote name='Mr. Foxen' post='1051714' date='Dec 8 2010, 02:22 PM']That is amazing, he was supposed to be fighting for them, unless he was some sort of communist who was fighting for North Vietnam against the south who make things for export.[/quote]


I dont claim to be that up on modern states but are you sure you dont mean Korea?

Isnt Vietnam now the Socialist Republic of Vietnam with no North and South or am I completely round the bend?

[quote name='Mr. Foxen' post='1051714' date='Dec 8 2010, 02:22 PM']That is amazing, he was supposed to be fighting for them, unless he was some sort of communist who was fighting for North Vietnam against the south who make things for export.[/quote]

Perhaps it was a malicious post, I have no idea of the status or opinions of the original poster, but it did cause some controversy on one of the US based forums.

[quote name='oldslapper' post='1051699' date='Dec 8 2010, 02:10 PM']It's a production over run cab, with a Celestion in. I put an Ashdown grill on. Not sure how the Ashdown Mk1's were configured? The 1x15 is surprisingly light and, imho, quite bright for a 1x15, without losing any bottom end. How's yours?[/quote]


TBH I like the weight of the 15 but prefer the 4x8.
However, following that discussion with Stevie and phil star about changing the driver on your combo, Im in the middle of putting some wadding in the 1x15 which may make a difference.

Whichever way, its a great little combination to use the combo with one of the minis

If you go to the Gotoh web site

[url="http://www.hosco.co.jp/HOSCO_ENGLISH/Pages/Gotoh.html"]http://www.hosco.co.jp/HOSCO_ENGLISH/Pages/Gotoh.html[/url]

They have drawings of various size tuners thay may help.

Alternatively, look up bassparts resource

[url="http://www.guitarpartsresource.com/middle_bass.htm"]http://www.guitarpartsresource.com/middle_bass.htm[/url]

They have some measurements that may help you

The 15 is interesting as it looks as if the driver is offset and there is a front port. Mine which is the mk 2 with the center badge and oval handles.has two rear ports and the driver is central.

Outsourcing to vietnam in particular didnt go down that well with some americans. I remember reading a comment from an ex Ampeg employee who said thirty years ago I was fighting them and now they have taken my job

Great little combo, and works well with either of the ashdown minis

[quote name='BurritoBass' post='1034519' date='Nov 23 2010, 10:19 PM']My Ampeg SVT USA 15E is rumoured to be ex-Wurzels and I challenge anyone to come up with a cooler naff link![/quote]

My acoustic 370 has a stencil remaining for Steps

Make sure you have plans to deal with rain.

Is it a covered area, could the electrics get wet.

I am sure there are knowledgeable people who can give more advice than I can but wet and damp conditions don't mix well with electricity

Electrical safety is key

Bought a paisley precision from Jo, very nice and professional dealing.