coilaudio

Re: Altec 250su any experiences
« Reply #40 on: April 14, 2015, 02:19:53 PM »
High filament voltage will definately shorten tube life, and eventually cook them totally.

Resistors work great. I normally put low ohm wire wound resistors in all AC filament supplies. They act as an inrush limiter to help prolong tube life. Also, most filament transformers expect to see 110-115 on the primaries. Especially  older ones. City utilities tend to run at 117 to as high as 126v to keep up with current demand. You can also use a variac to set it for perfect 6.3. It won't affect the b+.
if i had more time, I'd say less.


bieckmusic

Re: Altec 250su any experiences
« Reply #41 on: June 06, 2015, 12:13:58 AM »
So I got sidetracked with projects but I'm back at the altec 250su project. 

I think I'l try the resistor route first...

so to  get my 6.3 volt ac supply down from 7.3 vac
do you think some resistors like this would work?

http://www.mouser.com/ProductDetail/Bourns/PWR220T-20-R500F/?qs=sGAEpiMZZMu61qfTUdNhG7dNYlvJJaAMdpsmg3LfNdQ%3d

they're 20watt, they didn't have 10watt on mouser...  that's just the maximum rating so usually going higher is no problem it's just going with a lower rating that can cause problems..?

wiring in series, does that mean wiring one resistor off each leg of the ac source (the 6.3 v ac supply of my heath kit power supply, to bring the 7.3down to 6.3.

thanks again!!
Greg  :) :)

bieckmusic

Re: Altec 250su any experiences
« Reply #42 on: November 14, 2018, 05:03:06 PM »
So, I started this thread when I got a defunct Altec 250su some years ago...  Anyway, now it's working and it sounds amazing.  I haven't got everything sweetened up yet, need to build snakes and check some original wire routing. 

What an amazing sounding pre-amp!  so cool


tony hunt

Re: Altec 250su any experiences
« Reply #43 on: November 15, 2018, 01:44:49 AM »
Thanks for the update, I had never seen this thread before. It is a good one.

bieckmusic

Re: Altec 250su any experiences
« Reply #44 on: December 28, 2018, 10:27:20 AM »
Next mission:

I need to add a pad to the altec 250su.  There is just way too much gain to use the mic preamps for drum tracking.

searching around I found this really cool page about pad circuits

http://www.uneeda-audio.com/pads/

So off to see what sounds good...     8)

EmRR

Re: Altec 250su any experiences
« Reply #45 on: December 28, 2018, 10:29:50 AM »
Standard 20dB U pad.  I don’t understand why this wheel gets reinvented every 5 minutes. 
Best,

Doug Williams
Electromagnetic Radiation Recorders

"I think this can be better. Some kind of control that's intuitive, not complicated like a single knob" - Crusty

"Back when everything sounde

bieckmusic

Re: Altec 250su any experiences
« Reply #46 on: December 28, 2018, 11:18:18 AM »
sorry I posted, I won't post anymore about it.  My Apologies.

EmRR

Re: Altec 250su any experiences
« Reply #47 on: December 28, 2018, 11:25:06 AM »
Well that’s an overreaction.   There’s a zillion threads here there and everywhere about mic pads.  Spend a while with them. 
Best,

Doug Williams
Electromagnetic Radiation Recorders

"I think this can be better. Some kind of control that's intuitive, not complicated like a single knob" - Crusty

"Back when everything sounde

bieckmusic

Re: Altec 250su any experiences
« Reply #48 on: December 28, 2018, 11:42:20 AM »
Excuse me, I was just happily posting my progress.  I was sharing a link that I was thinking was helpful.  I didn't actually ask for help, especially for your chiming in.

I've built 10 pieces of diy including restoring the altec.   TG limiter, API's, LA2a, SSL compressor, 1176... 

Internet trolls, who jump on the backs of people and make them feel bad, really just need therapy and someone to tell them they love them.  I love you man, and your posts...

Man I'm not angry, it's no big deal.  20 dB pads are not personal for me...  LOL  I'm having fun with my DIY, not trying to give anyone a bad day.

All good on my end.  But pad's are complicated they're is some math involved.  and though it's super simple easy for you, it's not in my wheel-house...

So I'll take my business elsewhere.  I've wasted enough time thinking about you.

EmRR

Re: Altec 250su any experiences
« Reply #49 on: December 28, 2018, 11:50:10 AM »
There was nothing angry in my post.  Context is always lost in print.  It’s a fact; this wheel gets reinvented every 5 minutes for reasons I don’t undertand.  Exactly what I said. 

I thought you no longer owned this console anyway, so that’s confusing too. 

Would you know if I was trolling you?  THAT’s trolling.   
Best,

Doug Williams
Electromagnetic Radiation Recorders

"I think this can be better. Some kind of control that's intuitive, not complicated like a single knob" - Crusty

"Back when everything sounde


bieckmusic

Re: Altec 250su any experiences
« Reply #50 on: December 28, 2018, 12:01:38 PM »
what are you talking about?  i own it...I'm using it right now.

go away...  mess with someone else...

JohnRoberts

Re: Altec 250su any experiences
« Reply #51 on: December 28, 2018, 12:30:30 PM »
what are you talking about?  i own it...I'm using it right now.

go away...  mess with someone else...
Chill some old timers (like me too) grow weary of plowing the same field over and over, while its still news to somebody.

Keep posting or not... Only you can let other people bother you.

JR
Visit https://circularscience.com to hear what properly "cleared" drums sound like.

bieckmusic

Re: Altec 250su any experiences
« Reply #52 on: December 28, 2018, 12:44:42 PM »
My point is no one asked for the rude comment.  I wasn't asking a question in my post.

No field needed to be plowed.  I just caught EMRR when his blood-sugar was down apparently...

Maybe the old timers should "chill" and loosen up a little...