Bad Amp-share....

[Mr. Foxen]

Mod your rigs to XLR input only and have appropriate cable.

"Can I use you amp?"

"Sure, its good to go, just plug in when you want to play."

[Goes up to it holding a jack plug.]

[charic]

[quote name='Mr. Foxen' timestamp='1324998521' post='1478982']
Mod your rigs to XLR input only and have appropriate cable.

"Can I use you amp?"

"Sure, its good to go, just plug in when you want to play."

[Goes up to it holding a jack plug.]
[/quote]

You sir are an evil genius, although I think we can go further with this

[JTUK]

Half expected a support band to ask to use my rig recently...and I would have been open to it as the arrangements for the gig was all ours and we sort of knew the band, and I would have brought a spare amp along ..had he phoned me to ask, but there was no way I was going to 'hire' it out on the night.

As it happens, he didn't ask, but all it would have needed was a courtesy phone-call prior, in this case.

In general, I carry my kit so others can carry theirs...

[bumnote]

[quote name='4-string-thing' timestamp='1324739023' post='1477478']
I replaced the 2 15's in my old Acoustic cab with 2 Eminience Beta's to increase the power handling..
[/quote]

hang your head in shame

[attackbass]

[quote name='Ed_S' timestamp='1324998307' post='1478979']
Completely fair play if he was being rude to you, but personally I'd find that request many orders of magnitude less irritating than the ones who rock up and just expect to borrow something to play through with no prior arrangement. Number of times I've had people half-ask / half-tell me that they intend to plug into my rig when they blatantly have nothing of their own with them (not even a DI box), usually without even so much as a nod or a thumbs-up as they walk off, is untrue. I'd feel much better about letting them plug in had they clearly brought a gig-worthy combo with them, but came up and said "...yours is much better and it's already on stage, and since all I need is basic clean, do you mind?".
[/quote]

Yeah I've had that problem before and my reply has been 'That's not my problem!'. If anything I feel like the person needs to learn a lesson and know it's not acceptable to just presume they can use somebody else gear. It just irritated me that he had something decent to play through that was fine for the gig. There was no need for him to use my gear. My rig was already up there but we had to carry it down a flight of stairs (a flightcased Orange 8x10 and AD200b head...) and would have to carry it back up. My band is a professional touring band and in these circles most times the agreed thing is that headliners don't share thier backline unless space is an issue and then if the band is cool a cab share is usually possible.

[4-string-thing]

[quote name='bumnote' timestamp='1325001746' post='1479012']
hang your head in shame
[/quote]

Still got the originals though, and when my replica cab is built, they'll be going back in! Mind you, the solder won't be original and I'll have devalued my cab....

[Prime_BASS]

Never really had a disastor with sharing my stuff. As you can see from the Bring me my instrument! Its not cheap gear.
I always set it up for the user and remind them that as long as the blue light isn't flashing loads its ok, and that changing the knobs does nothing as its going straight to a desk.
Or if we don't have a PA I set up the sound.
Usually the other bassists are to nervous to touch it anyway. I'm surprised that 90% of gigging bassist do not understand basic amp controls.

On the point of him breaking being a complete douche. He is liable due to him willingly taking responsibilty of the gear and due to his neglagence he broke it. Although did you not notice any nasty noises during him playing? Or it being way too loud? .

I'm surprised the amp didn't cut out due to heat protection though, are sure this didn't happen?

[tombomb]

Cheers for all the posts guys.
Hope you all had a great Christmas.

Waiting fir wembly speakers to get back of hols now!

Since the first post I've got all my gear back (my guitarist was looking after it)
Pretty sure it wasn't amp as it has an xlr out which we used when the speaker stopped which was fine (although could be on a different part of circuit I suppose)
Taking the front off the cab though, the cone grinds like buggery, very tough to move. Don't have meter at home but pretty sure that's the issue right?

There's an 18 svt for sale on here, think I will get a recone, then upgrade!!

[Prime_BASS]

Some amps still pass a signal straight to the di in case of an amp failure.

Although if the cone doesn't move I expect that its buggared.

[JTUK]

If the coil travel is impeded, than a recone or new chassis is the only way out of that

I would suggest the guy has fried your rig ( speaker)

You need..as others have said..to be sure of a complete matchup of new speaker, so that means that Wembley LS needs to have cone kits of the model you need.
If they have another kit..you could get all the probs above you are trying or wanting to avoid.

You need exact like-for like or you need to be able to mod the different specs..as people have said.

This is the problem we all get with discontinued lines... and limited info from the makers.

[Big_Stu]

[quote name='tombomb' timestamp='1325154758' post='1480239']Taking the front off the cab though, the cone grinds like buggery, very tough to move. Don't have meter at home but pretty sure that's the issue right?[/quote]

[quote name='JTUK' timestamp='1325157481' post='1480293']
If the coil travel is impeded, than a recone or new chassis is the only way out of that
[/quote]

If something is "grinding" it sounds to me like the magnet issues, will a recone fix that?? (Asking, not denying btw)
I was at a gig once where a magnet was well seized to the point where the speaker started smoking with being unable to move but still getting a signal.

[JTUK]

My reasoning is the magnet position is fixed and the coil and cone will 'travel'..if the coil overheated or does not travel back and forth on line, then either the cone suspension is shot and distorts the travel
or the coil has fried or ruptured or however you wish to describe it..and therefore rubs up against the magnet.

[tombomb]

Update!

After a busy month I'm getting round to sorting this out.
I think the best option for me at the moment is to put at driver capable of handling more power into my cab.

So what are people's thoughts.
Amp spec: 350W at 4Ohms, (500W at 2ohms)
Previous (blown) speaker: 200W, 8Ohms

New Requirements (in my mind):
400W+ Speaker
4 Ohms
15" (the speaker...)

Options so far:
£100 (400W) - http://professional.celestion.com/bass/pdf/BN15-400S4.pdf
£150 (450W) - http://www.eighteensound.com/index.aspx?mainMenu=view_product&pid=233

I have a pretty limited knowledge of these things but from the bit of research I've done the celestion's xmax of 2.5mm is pretty lacking compared to the 6.5mm of the 18sound, but I appreciate that this isn't the only factor.

Would be very greatful for any feedback.

[Merton]

Just because a driver is thermally rated higher than your amp doesn't mean it will be any better than the original driver in that cabinet. Lots to take into account I'm afraid and xmax is certainly one of them! There are better people than I on these forums who can explain more succinctly for you tho

[discreet]

[quote name='Merton' timestamp='1327960644' post='1519660']
Lots to take into account I'm afraid and xmax is certainly one of them!
[/quote]

+1 Excursion is all-important as far as bass is concerned:
[url="http://barefacedbass.com/technical-information/understanding-power-handling.htm"]http://barefacedbass.com/technical-information/understanding-power-handling.htm[/url]

[tombomb]

Ha, I look forward to hearing from them!
Though I was getting the hang of it all.

Cheers Discrete, I've read that article from Alex (and a lot of his stuff, very helpful)
I figure if I have a higher rated speaker to minimise thermal limitation and a biggish xmax to minimise excursion limitation I'd be in a reasonably good place...
So with Merton's input I'm now less confident in what I though I know!!

[Mr. Foxen]

Cab needs to be tuned appropriate to the driver, otherwise the excursion goes nuts at a certain frequency at not much power.

[tombomb]

Cool. I can do that I gues based on these links. Second one looks easiest to access but prob worth going through that wiki book to learn a bit more about it.

New to all of this but is it standard to tune to the lowest frequency you'll use, so in my case 41Hz?

[url="http://en.wikibooks.org/wiki/Engineering_Acoustics/Bass_Reflex_Enclosure_Design"]http://en.wikibooks.org/wiki/Engineering_Acoustics/Bass_Reflex_Enclosure_Design[/url]
[url="http://www.mobileinformationlabs.com/HowTo-1Woofer-Box-CAL%20Port%20lenth%201.htm"]http://www.mobileinformationlabs.com/HowTo-1Woofer-Box-CAL%20Port%20lenth%201.htm[/url]
[url="http://www.ronshaw.citymax.com/f/Designing_Bass_Reflex_Loudspeaker_Enclosures.pdf"]http://www.ronshaw.citymax.com/f/Designing_Bass_Reflex_Loudspeaker_Enclosures.pdf[/url]

[LawrenceH]

[quote name='tombomb' timestamp='1327996729' post='1519925']
New to all of this but is it standard to tune to the lowest frequency you'll use, so in my case 41Hz?
[/quote]

No, a lot of cabs are tuned a fair bit higher than this - even Alex's stuff I'd imagine will be a few Hz above. There are three major considerations - one, what a bass guitar actually outputs at various frequencies, two, what these frequencies contribute to the overall sound you perceive, three, how a reflex ported speaker behaves either side of cabinet resonance.

The first is very dependent on the instrument but without a lot of equalisation (think active pre with bass boosted) most basses playing an open E (or open B on a five string) will output less fundamental than octave harmonic. On the other hand though, string 'thump' rather than a note itself means a bass can easily generate substantial output well below 40Hz.

The output curve of a bass guitar note relates to the second issue, that harmonic series is what tells your brain what bass note you're listening to more than the root itself and also that a lot of the 'power' you perceive from those low notes is actually from the harmonic of the octave above, around 60 to 120Hz. That's not to say you can't hear/feel the real lows, but most people playing without subs do well enough without them. So don't worry if your cab starts to roll off above 40Hz (nearly all do, they'd have to be ridiculously large in size not to). Room modes in the bass frequencies are also a complicating factor, too much bass can be a bad thing in a lot of situations.

The third point about speakers is perhaps the most important - either side of cab resonance is where cone excursion rises, and if you tune too low then you get a region of high excursion right in the 'power' band around 60-80Hz. On the other hand tune too high and your cone excursion, which rises very rapidly as frequency falls below resonance, becomes a real problem. So it's a balancing act. An awful lot of cabs are tuned between 50 and 65Hz, and that is a range that seems to work well in practice though the higher tunings do tend to mean low notes, especially with bass boosted by EQ, will cause speaker 'fart out' if you're pushing things hard.

Edited January 31, 2012 by LawrenceH

[LawrenceH]

[quote name='tombomb' timestamp='1327958442' post='1519595']
from the bit of research I've done the celestion's xmax of 2.5mm is pretty lacking compared to the 6.5mm of the 18sound, but I appreciate that this isn't the only factor.
[/quote]

Bear in mind that if Celestion reported Xmax the same way that 18sound did, they'd quote a figure of 4.5mm. However the 18 Sound is a much higher spec driver

[tombomb]

Awesome. So essentially I want to tune a bit higher than 40, but too high and I risk farting when pushing the lows. Makes sense.
What about tuning lower than 40, say at 30-35? Would that help support the 60-80 range (being roughy an octave higher?)

Also, how much does it really matter? Will it be a really noticable about of drop off?

It looks like the previous driver had a natural frequency of 38, the 18Sound's is 39, so not too different. (But again I'm probaby missing something and it's not just the natural frequency that affects the tuning)

It's a decent enough cab already so reckon I'm gonna go with the new speaker, fit it and try it out. If I notice drop-off I now have a bit of knowledge to do something about it.
More likely, (since I've been playing less than a year, and haven't as yet settled on a "sound") is that I wont notice the difference!!

Also, cheers Lawrence - seems crazy that different manufacturers report the same property in different ways.

[LawrenceH]

[quote name='tombomb' timestamp='1328048847' post='1521083']
Awesome. So essentially I want to tune a bit higher than 40, but too high and I risk farting when pushing the lows. Makes sense.
What about tuning lower than 40, say at 30-35? Would that help support the 60-80 range (being roughy an octave higher?)
[/quote]

No, afraid it's the opposite, tuning lower means you get less volume up higher (80Hz region) and the cone will also move more potentially breaching xmax. Tuning lower protects the speaker below 40Hz at the expense of higher up.

[quote name='tombomb' timestamp='1328048847' post='1521083']
Also, how much does it really matter? Will it be a really noticable about of drop off?
[/quote]

This is a good question, it depends on your sound preferences and how good you are at noticing! In my opinion a smoother roll-off is desirable but not often seen on a bass cab, and really it's not always such a massive problem. More noticeable than drop-off is when a driver has a boomy one-note bass type response, which relates to the next thing you ask:

[quote name='tombomb' timestamp='1328048847' post='1521083']
It looks like the previous driver had a natural frequency of 38, the 18Sound's is 39, so not too different. (But again I'm probaby missing something and it's not just the natural frequency that affects the tuning)
[/quote]

Other factors are important which describe the electromechanical properties of the driver (Thiele-Small parameters) and together these describe the low frequency behaviour of a given driver in a given box/tuning. Manufacturers supply these specs. Luckily there is free computer software that lets you model the behaviour of a system based on these T/S parameteres including frequency response and cone excursion. A good program is WinISD pro alpha, if you're serious about cab design this is where to start and it isn't all that complicated. Obviously though, a frequency response plot is all very well but you need to relate that to what your ears hear to make sense of it in the real world!

Good luck, fwiw I'd guess both those drivers will do the job with the 18sound being more 'bomb-proof' due to higher excursion capability. But the ampeg port sizes are quite small, this means you will likely not be able to get maximum bass from the 18sound without it 'chuffing' (air speed through the ports around box resonance is too high, messes up the port behaviour and sounds bad - solution = bigger ports lengthened to maintain correct tuning, down-size is it eats up internal box area)

[tombomb]

Cheers Lawrence. Really good advice, which I shall heed.

I've ordered the 18sound. It comes tomorrow. I can't wait.
I'm going to spend some time with my ears, and with WinISD seeing what I can learn!

Ashdown Bass Drive Plus also arrived today, it's going to be a great weekend.

[tombomb]

Right, Jan was a good month.
New speaker, pedal (from bc), cab-case (from bc).

Given the way this thread started I could end it with an opposite and much happier story from our first 2012 gig.
We were put on to headline and happily shared my backline - this time to some people with brains in their heads.

Absolutely crappy house kit, the floor tom kept falling over! But it's about having fun right
Good fun gig. 10 months into starting playing and my 10th gig ever I'm actually starting to enjoy this music malarky!!

[attachment=99888:good ship.jpg]

[LawrenceH]

Great! Is that with the 18Sound? How is it sounding?