Ted

[quote name='JMT3781' post='1357768' date='Aug 31 2011, 05:40 PM']yeah man.. its for someone i think we both know... not sure he wants to pay 100 quid though, so most likely ill be sticking one of the cheap new fanes in there[/quote] Don't do it. The speakers in these are more like giant hi-fi speakers - they've got foam surrounds and about 3cm of cone travel. Put almost anything else in and its going to sound sh*te.

I've got Labella 760FXs on my Jazz and Epiphone Jack Casady and love the sound of them. D'addario Chromes on my OLP Musicman are altogether smoother. I really like the sound of TI Jazz Flats but I don't like the feel of them - their tension is so low they seem to roll out from under your fingers. I just put some 1954 pattern Labella 760Ms on my Yamaha BB300. They sound incredible - deep and big and grunty. Completely different to the lighter gauge Labellas It is like playing hawsers - very thick, very high tension. I had to give the truss rod a quarter turn to straighten the neck when I put them on. There are anecdotal reports of them wrecking the necks of modern basses.

AH300s have an overheat switch on the main heat sink. If the fan isn't running it trips after a few minutes playing. possible reasons for the fan not running- loose wire to terminal block on pcb, the not very robust mounting of the fan regulator heatsink (thats the small one at the fron of the board) causing a break in the solder or pcb track to the regulator.

Its mine. I really didn't want to sell it, but when you're skint thats how it is. I was surprised nobody wanted it at £500. I actually prefer the sound of Bartolinis to Aeros.The humbucking Nordstrands it came with made a horrible clangy sound. A pair of Aeros would have cost nearly £250 I went with the Barts. Cheers Ted

Rich B15Ns come in three basic flavours 60 - 65 - Black or Blue Tolex, Square double baffled cabinet. These are the most expensive 66 - 68 - Blue Tolex, Square single baffled cabinet. 69 - 80 - Black Tolex, rectangular ported cabinet. least expensive (they made a lot more of them). They all sound great. Non original parts (e.g. speakers) reduce the value a bit. Originally it would have been fitted with a square magnet CTS or Eminence. Jess Oliver (the designer of the B15) recommends Eminence Deltas. The early ones have the classic woofly Jameson sound. The post 68 ones have a slightly cleaner sound. Because they used a tuned cabinet design they are more sensitive to speaker changes - even getting the originals reconed with modern materials can give you resonances which completely screw up the sound. I think I saw the amp you're talking about on Ebay - it had a 240- 110V step down transformer which I suspect is whats actually been PAT tested rather than the amp itself. I'd pay £750 top whack for the amp in question. If you want a B15 serviced I can do it for you, if you're near London. Have a look at my website: www.valveamp.net Cheers ted

[quote name='Oxblood' post='20185' date='Jun 19 2007, 01:47 PM']It's [i]very[/i] unlikely that replacing valves would get rid of hum, unless that hum is being caused by poor inter-electrode insulation between the heater and cathode of one or more valves - but unless the seller has access to a valve tester, he wouldn't know that. "[/i][/quote] I just had an Ampeg B-15N in which hummed like a bastard - it had two completely different types of 6L6 in the output stage, one of which was on its last legs. A pair of new, matched valves got rid of the hum. Push-pull output stages rely on valve matching to cancel hum - although the matching doesn't have to be very tight for it to work. This was an extreme case. TW