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I used all electrolytics in the higher voltage part of the supply but I used very good caps nonetheless.Usually for the doubler I use the Pansonic ED series 820uf caps that McShane sells in his wonderful kits but I went with the 560uf Epcos LL which I believe are the high grade Philips that also top grade..I did this because there was more connection material to solder wires to other caps and to the output trafos.Anyway,this is far and above improved from what the original scheme was being you have about three times the original capacitance in most places and it is laid out much more neatly and it's much more quiet.
I took particular note with the preamp and tuner section where extra decoupling capacitance makes the S/N ratio lower on measurement.
Honest amplification is better than excessive 2nd order distortion anytime.
Follow Ups:
Open them up and re-stuff?
-reub
I put two JJs on top and one of the doubler caps.I don't restuff cans.I think it's a bad practice.McShane did a very good job selecting caps and layouts for the way a vintage amp should be done and the caps that people stuff in cans are meant to be in a ventilated area..There is a lot of electrolyte in the old can caps and that assists with cooling.
I do restuff the leak cans on occasion but a dual 100 F&T fits like a glove and there is plenty of room left over for the cap to ventilate. A JJ fits the leak cans as well.
If you look at the original cans in the 500c,there are about 8 or 9 sections.You have the doubler caps making up 2 sections,you have a paralleled set of 20s or 30s which you use a single 100uf section for,then there is one cap off each 470 ohm resistor which did as a single on each under the chassis along with the second doubler under the chassis.The 4700uf replaced the paper electrolytic underneath the chassis.
Honest amplification is better than excessive 2nd order distortion anytime.
Edits: 05/29/14
With the three Fisher units I did years ago, none of the can caps needed replacement after reforming. They measured good, with no hum. I didn't want the chassis to have a big kluge, with new electrolytics hanging, so I left them alone. Never a problem in mine. 800C, 500B and Fisher console amp.
YMMV
It's not a question of IF they will fail, it's a question of when. With all due respect I believe that parts that have aged beyond their typical lifespan should be replaced. And the good news is the new parts are FAR superior in nearly every case. With a bit of care and creativity I find that you can install parts that while not original in appearance DO look "right" in the unit you are rebuilding. When I assemble the parts kits for the various units I do take into consideration how the unit will look when it's done, and sometimes a bit of compromise in one area will benefit another.
That's my $0.02 worth anyway.
Hey Mikey Samra - I've been popping Claritin like candy this year too, and I'm doing fine allergy wise. But hanging on to my youth - errr, not so much. I hit the big 63 TODAY!! And that big expensive present you bought me hasn't arrived yet, but I'm sure it will! :~)
Don't feel bad.I hit the big 56 in a couple weeks.I'm popping Zyrtec which is pretty much like Claritin but I've been using a nebulizer which helps a lot.
Honest amplification is better than excessive 2nd order distortion anytime.
Do you offer a "parts kit" for the power supply caps for a Fisher 400? Never thought to ask....just "assumed" you only offered kits for the citation.
Citations
Macs
Eicos
Fishers
Scott
Sherwoods
and more
Macs and Citations are his most common of the bigger stuff I would guess.
Honest amplification is better than excessive 2nd order distortion anytime.
I have kits for most of the common Fisher models Russ - including the 400. Thanks for asking.
,
Pete
This one isn't mine and I have six if my own however,there is only one underneath that I put in separate and it actually better than it did originally if you saw that big ugly paper electrolytic.The red one is a poly in the tuner which makes a big improvement.I did replace the brown one on the angle with a physically smaller cap and ran short wires and now it looks even better..THe can caps are ticking time bombs after 50 years...They fail without notice like a 90yo woman with a heart condition.
Honest amplification is better than excessive 2nd order distortion anytime.
Edits: 05/29/14
Hi Mike;
I hope you've gotten those allergies are under control - sheesh!
Between that and the kidney stones earlier this spring I would think your due a break.
The Fisher looks so neat and clean under the hood and got me thinking; Do you do any FM tuners as well?
If so, as soon as your done with my Sherwood S-5000 I would like to have my 2200 tuner gone through as well.
Take care.....
Stac........
........I was a vegetarian for 15 minutes... until the main course.
Sherwood 5000 - are you gonna be happy!
I can't see having anything better after mine was restored and rebuilt by Mike.
Enjoy
charles
Charles;
Not to hijack the 500-C thread, but......
That's great news and I can't wait. I've been reading your posts the past couple of months since you received your M. Samra limited edition S-5000 and you seem well satisfied to say the least.
I talked with Mikey (allergies were kicking his ass and he sounded awful - poor guy) the other day and he said it's basically done and he's just running it in to make sure nothing weird pops up before he ships it back.
I couldn't believe how good the little Sherwood sounded in bone stock form so in a leap of faith I and sold off a bunch of other stuff since the Sherwood already beat the hell out of it. Once the Sherwood has been "Samra'd" I'll probably get off the upgrade merry go round on concentrate my efforts elsewhere - cables, room treatments, or wait for it.......Music.
I have a friend that has a couple of nice integrated amps from Pathos and Pass that wants to compare them to the Sherwood once back. It should be interesting and I wouldn't be surprised if the mid century stuff spanks the modern......
........I was a vegetarian for 15 minutes... until the main course.
Look into good tubes. I'm using ribbed Telefunks (sp?) in the preamp. It really does make a difference!
charles
I will do just that.
I have the strong original Amprex 7189's power tubes and the original 12AX7's as well as the rectifier.
Where did you find your ribbed Tele's?
I have been perusing Brent Jesse and Jim McShanes site(s).
........I was a vegetarian for 15 minutes... until the main course.
They came with the amp.
But DO get a nice matched set for the preamp. Especially the three linestage tubes!!!!! It DOES matter!!!!
charles
Allergies under control and school is out and while kids are enjoying youth,I'm fighting to keep mine and I'm getting caught up on stuff.
Honest amplification is better than excessive 2nd order distortion anytime.
Hi Mike! Unrelated but did you get my messages about the 1000a? Hadn't heard back so posted here.
Best,
Dave
Let me check...I have been email issues again lately with yahoo so I'm switching to Gmail. Got it and answered you and the receiver is great as long as it has tubes in it for that price.
Honest amplification is better than excessive 2nd order distortion anytime.
Edits: 05/28/14
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