new 10 - 25 year old system

hello all.

thanks to the webmaster for this forum and experienced contributers.

last few weeks i had a bit too much free time and picked up a phase linear 700 series two. a c 4000 pre. and als mk iv platinum. all from different sources. hooked it up yesterday. the speakers sound nice. a little low on the bass. i bought these at a store and compared with b&w. b&w were nicer, heard the difference in bass output, but more$$$. so i bought what i went there for, the als. went to boston for speakers from exit 10 on jersey pike. there is one more pair of mk iv platinum at spearit sound in boston. 4 x 12" + 60" ribbon.

i was surprised at the low volume level of these speakers. reading these forums i see 350w a channel may not be enough. volume is not that important to me now, but i was surprised. a friend had - i believe a phase linear 400 and if he turned it up it was painful. it eventually cracked the walls in his house. but he was not driving als.

i bought the amp on ebay- "works good- as is". yeah works good for a few minutes. i opened it up and see some burned items and looks to me like some mods. trying to get manuals now to find out what is supposed to be there, what is not.

i guess i need to determine if amp is working properly and if i am using amp correctly. i am not used to a lot of this jargon. how do i know if i am over driving? what am i over driving, the amp? how do i know if i am clipping?

my roommate (very good at repairing cb radios) opened the amp to inspect and clean and told me i may have set the sensitivity of amp too high at first (those aren't volume controls ) but when we tried it again i blew a fuse in one speaker.

waiting for manuals, if anyone has advice feel free.

Welcome to the forum.

It sounds like the amp has issues and if I were you I wouldn't use it until you're sure those issues are fixed. The Plats will spank anything from B&W, but will require lots of clean, high current power to do it. IMO, B&W speakers are lifeless. The Plats will go to 17Hz with little effort when feed that kind of power, so I'd have to say the power used for your demo wasn't up to the task.

Over driving is when you push the amp into distortion which in turn causes the speakers to clip. You'll know it when it happens, it doesn't sound good at all. Bad things can happen to both the amp and the speakers when this occurs, so keep the volume dial below the halfway point and you should be ok.