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Paul Barker
No idea why I do this anymore
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Post by Paul Barker » Wed May 30, 2007 8:25 pm

thans nic

Cressy Snr
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Post by Cressy Snr » Wed May 30, 2007 8:27 pm

I've got to get on with it now cos all the bits are arriving.
I cant leave it fallow. Not after all the work that went into designing it.

It'll be about three weeks before the custom wound mains TX arrives so
the amp won't be ready for Egg5 but I'm sure Steve will have one of his little meets before Egg6/Whitham. I'd like to hear what it can do with his baffles.

Steve

Darren
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Post by Darren » Wed May 30, 2007 8:27 pm

It sounds (if I read your message right) you have lost 6 y j and spacebar?

I used to get this quite often with an old dell laptop.
The cure was always the same thing, pull the keyboard ribbon and re-insert. Then everything would be fine for a while.

I assume it was an oxidised connection, you may need to be a little more drastic than simply pulling and re-inserting the ribbon?

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Nick
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Post by Nick » Wed May 30, 2007 10:15 pm

Thats alright Paul, I am used to reading creative typing, I do enough myself. My worst problem, is the definite article always comes out a teh.

I found I am not alone http://en.wikipedia.org/wiki/Teh

simon
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Post by simon » Wed May 30, 2007 11:47 pm

Welcome Mark, Steve and Steve!

Aye, another good night last night, and it was nice to finally hear those WE300As in my WE91s. Lovely, lovely valves. If you ever decide you can live without them Steve then I would be very pleased to give them a happy home. :)

Hopefully I'll get chance at the weekend to try shunting the Alps pot in the 2A3 amp and the Vishay Dale stepped attenuator in the passive to see if they were adding the suspected greyness that wasn't there when Ed's Squeezebox was connected directly to the WE91 monos.

I thought your open baffles were sounding very nice last night Steve - looking forward to the next version with 2 bass drivers.

Simon.

steve s
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Post by steve s » Thu May 31, 2007 9:23 am

thanks simon .. steve came to collect the el37's a should have lent him a pair of el35s too.. i suspect they would be similar to the 37's.. dont take quite the current

simon brought his new 2a3 amp and his trusty 300b to ty the 300a in

the 2a3 was quite good.. but on the night the 300b with simons valves was better.. quite a good night for me..
the baffles did not disgrace themselves they are ok unless i put more than 3 watts of very heavy bass through them.. the speakers start sound stressed... as they do in free air without a real load.. goodmans in the sixties did not recomend ob for there 301's
but with the sound i'm getting i don't see me going back to horns...
did i write that!!

as simon hinted i got a pair of audium 61's coming today, there is 2 versions.. i've got the 35 hz ones they are the bass version of the 301 so the sound should blend in, the efficency is very close to the lowther .. as good as match as i could imagine.. the 301 and the 61 share the same magnet/basket/pole and use a 16.5k line magnets giving a total of 1.85 tesla .. the lowthers are 2.2 tesla.. this is very high for older speakers
(ex2 are 1.75 tesla..and i know magnet strenght is not everthing but it does improve transients speed and detail and of course the damping factor.. the reason lowthers don't do bass without some form of help)

normally 2 bass speakers are used to get the 3 db extra in the bass.. i dont need that, so it means i can build a narrower baffle and have enough extra so the bass output can be reduced to match the lowther level and putting 2 bass speaker close will help smooth out the peaks a little.. that should improve the quality of the bass further...

there's so much you can do with baffles to smooth/ even things.. without resorting to the electronics side...
from what ive learnt so far.. you can just knock anything up and it will sound ok.. but.. there is more to it.. very much like SE amps really

steve

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Nick
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Post by Nick » Thu May 31, 2007 9:35 am

Simon, have you tried that small change I suggested with the VR tube current path?

I know it helped in the case of the driver I was using.

simon
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Post by simon » Thu May 31, 2007 12:56 pm

Not yet Nick, maybe this weekend. I'll have a look at what I've got and see if I can parallel something up.

Interestingly the oscillation came back on Steve's OBs, fortunately Steve had a couple of spare 30uF motor run caps and clipleading these to each channel did the trick. I need to get some big caps I think.

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Nick
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Post by Nick » Thu May 31, 2007 1:07 pm

I would try the change first, I wonder if the path through to tha cathode could be part of the problem thats causing the instability.

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Post by simon » Thu May 31, 2007 5:20 pm

Good point. I'll see what happens if I remove some of the C already there after the change.

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Post by simon » Fri Jun 01, 2007 10:56 pm

Well, I changed the C3g cathode resistors to 68R and connected the 0A2 cathode to earth rather than the top of the cathode resistor, but couldn't hear much difference. Think it's something I need to live with then change back to hear any difference.

I tried removing 10uF of the 54uF but the oscillation returned so put it back. Ella sounded so sweet tonight though. :)

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Nick
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Post by Nick » Fri Jun 01, 2007 11:42 pm

Ahh well, it won't be the first time I was talking tosh :-).

simon
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Post by simon » Sat Jun 02, 2007 9:34 am

Probably more my ears than you talking tosh Nick :oops:

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Nick
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Post by Nick » Thu Aug 16, 2007 1:17 pm

Just spoke to Pat, she is ringing me back tonight, but think sshe has two rooms for the 21,22 so that should match the three of us.
Resistance isn't futile it's V / I.

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Toppsy
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Post by Toppsy » Thu Aug 16, 2007 1:25 pm

Nick wouldn't your last posting best be on the "WF3 anyone going" thread?

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