Gavin has an 8 ohm 4x10 bass cab, this amp has a 7 ohm output (and a 15). I take it that'll work ok? Does the wattage of the cab matter? Presumably the cab's 450w or something.
Would the fact it's a bass cab make any odds? Help meeeee.
There was a time when Selmers were the last outpost of valve goodiness on a farm boy's wages. That honour now falls to WEM, mostly. And then there are all those old valve PA heads by Sound City etc. floating about out there.
Having said that, I wouldn't be at all surprised to dig up a few more c.£100-or-less Selmers before they become the new AC30s.
stewart wrote:Gavin has an 8 ohm 4x10 bass cab, this amp has a 7 ohm output (and a 15). I take it that'll work ok? Does the wattage of the cab matter? Presumably the cab's 450w or something.
Would the fact it's a bass cab make any odds? Help meeeee.
Using my limited knowledge of electronics i'm pretty certain this will work. I think it is the ohm rating of the cab that is important, not the wattage.
UlricvonCatalyst wrote:There was a time when Selmers were the last outpost of valve goodiness on a farm boy's wages. That honour now falls to WEM, mostly. And then there are all those old valve PA heads by Sound City etc. floating about out there.
Having said that, I wouldn't be at all surprised to dig up a few more c.£100-or-less Selmers before they become the new AC30s.
Old Carlsbro amps are worth a look too. I have a 50 Top from 1969 and it sounds awesome, it's a bit beat though and sounds a bit rickety when you carry it so I prefer to use my Bassman most of the time as it seems a bit more sturdy.
stewart wrote:Gavin has an 8 ohm 4x10 bass cab, this amp has a 7 ohm output (and a 15). I take it that'll work ok? Does the wattage of the cab matter? Presumably the cab's 450w or something.
Would the fact it's a bass cab make any odds? Help meeeee.
Using my limited knowledge of electronics i'm pretty certain this will work. I think it is the ohm rating of the cab that is important, not the wattage.
Yeah, ohm-age is the one to watch. An 8 or 16 ohm cab is close enough for the almost-corresponding outputs to cope with - just don't try it with a 4 ohm cab with the 15 ohm output or you'll risk burning out the transformer. (I think)
I have a 15 ohm cab in my shop, as it happens, but it's only a 1 x 12", so probably only about a third as loud as the 4 x 10" you mentioned. (Sorry if mentioning that breaks any rules.)
stewart wrote:Gavin has an 8 ohm 4x10 bass cab, this amp has a 7 ohm output (and a 15). I take it that'll work ok? Does the wattage of the cab matter? Presumably the cab's 450w or something.
Would the fact it's a bass cab make any odds? Help meeeee.
Using my limited knowledge of electronics i'm pretty certain this will work. I think it is the ohm rating of the cab that is important, not the wattage.
It does matter if the amp is more powerful than the cab is rated to handle (not the case here).
7 ohms from the amp is the load the transformer expects to drive - 8 ohms is the closest you're going to get on a modern cab and should be fine.
stewart wrote:Gavin has an 8 ohm 4x10 bass cab, this amp has a 7 ohm output (and a 15). I take it that'll work ok? Does the wattage of the cab matter? Presumably the cab's 450w or something.
Would the fact it's a bass cab make any odds? Help meeeee.
Using my limited knowledge of electronics i'm pretty certain this will work. I think it is the ohm rating of the cab that is important, not the wattage.
It does matter if the amp is more powerful than the cab is rated to handle (not the case here).
Am I correct in thinking that the total wattage of a cab should ideally be about 2x that of the amp you're using to drive it?
johnnyseven wrote:
Using my limited knowledge of electronics i'm pretty certain this will work. I think it is the ohm rating of the cab that is important, not the wattage.
It does matter if the amp is more powerful than the cab is rated to handle (not the case here).
Am I correct in thinking that the total wattage of a cab should ideally be about 2x that of the amp you're using to drive it?
Not really, amps are quoted in RMS (Root Mean Squared) output when dimed, and I think what you're alluding to is that transient peaks could exceed that wattage. In practise you can get away fine with a 50W amp and rated cab since none of us are playing Knebworth.
Great find Stewart!...i remember seeing old amps like these in a second hand shop in my home town in the early 80's when i was a wee nipper...we used to call him "Junky Jim" but there was fack all junky about those babys!!...if you tried to sell him something he would say,
"aahhh i had one of those in last week...", and then he'd give you a crap deal....
If ONLY i'dve been interested in music back then, i mayve scored one!(i was only 10 and didnt know any better)...
I remember reading articles in 90's guitar mags about them, in which they scoured music shops to see what you could get for your money cheepz, it was in those mags they built a cab and showed you how!...only took me another 10 years to start making one ha ha!...then when i did make one, i didnt get to hear it until another year afterwards when i scored my 100w all-valve cab off ebay for £130...
Fran's right, old amps are the Business!..my 80's Fender Super 60 combo has a glorious wood/dust heaty smell to it....and ive just scored a 1962 Fender Bandmaster 40w head for an embarrassing £40...deal of a lifetime!
stewart wrote:Gavin has an 8 ohm 4x10 bass cab, this amp has a 7 ohm output (and a 15). I take it that'll work ok? Does the wattage of the cab matter? Presumably the cab's 450w or something.
Would the fact it's a bass cab make any odds? Help meeeee.
Using my limited knowledge of electronics i'm pretty certain this will work. I think it is the ohm rating of the cab that is important, not the wattage.
It does matter if the amp is more powerful than the cab is rated to handle (not the case here).
7 ohms from the amp is the load the transformer expects to drive - 8 ohms is the closest you're going to get on a modern cab and should be fine.
Yeah, its very rare a cab will measure exactly 8 ohms or whatever anyway, for instance, mine reads 7.8 on a multimeter.
I think the Selmer says 7.5 or 15 on back, plenty close enough. Oh, i ran a bass cab with my Laney head for a good year or more Stewart, it will be fine.