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Old 26th February 2003, 03:13 AM   #11
Joel is offline Joel  United States
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I think you did fine. I agree - the iron is probably close to 3 or 4 hundred $. But looking at the build quality - which is ok, don't get me wrong - makes me wonder why you didn't just tackle it yourself? You'd need $150 in tools, but in the end it's a lot more rewarding - at least to me.
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Old 26th February 2003, 05:13 AM   #12
SHiFTY is offline SHiFTY  New Zealand
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It looks really nicely built, but it is a little industrial looking... You could improve it cosmetically.

How about getting a couple of pieces of polished wood and putting them down the sides? And really big volume controls.

Also that switch looks a little "basic", I am a big fan of old skool toggles.

If you did a few things like that it would really be "your" amp

IOW, pimp it up a little! Get out the chrome and blue LEDs!!!!

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Old 26th February 2003, 01:21 PM   #13
PassFan is offline PassFan  United States
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Shifty, you llike decorations don't you?
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Old 26th February 2003, 01:36 PM   #14
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Well, i'll let you guys in on a little plan that i have going.

You might remember if you peruse the analogue forum ( which i'm sure you do ) that i usually post questions about transcriptors turntables.

Well, i'm happy to report that my Saturn turntable with vestigial arm has been restored to its original glory by Michael Gammon. Now, everyone is going to say "well, it looks cool as hell but doesn't sound THAT great"....well, the looks are what i am going for.

I've got a local acrylic dealer whom i'm buying all black acrylic chassis from. ( thanks to peter and his gainclone for the ideas) I'm going to take all the aesthetic concepts in the Saturn deck and apply it to my other components....the 300b amp, a bottlehead line pre, ...still looking for designs for the phono stage, ....
But they will all be standard dimensions, with aluminum knobs, aluminum tops, ...etc if i can encorporate a blue LED on the saturn then maybe i will have one on each component.

So back to the point, the 300b amp chassis will be scraped anyways.....i just wanted a launching point...something to listen to while i build

-Maz
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Old 26th February 2003, 02:41 PM   #15
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Default Current capacity

A bit off the topic but do you all think the current capacity of the choke in the PS is adequate?

BTW, good luck with the amp; I have the parts to start from scratch and look forward to building after my SE El84 is complete.

Rick
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Old 26th February 2003, 02:59 PM   #16
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Hi,

Like CiscoKid, I too built the JE Labs 300b's. CK's and mine are both monoblock versions.

I would not scrap the chassis, paint it and but some wood on the sides. Paint the trannys too.

Replace the rca inputs and binding posts.

I also noticed that the caps are real small and notice only one small oil cap, the others look to be all electrolytic caps. I would start replacing those with bigger caps. Especially in the power supply. Angela Instruments carries the ones most used in scratch building the amp.

Resistors can be replaced with RikenOhm or Tantalum types in the signal path and non inductive types in the power supply. The little gold fin resistors can stay.

Wire used can make a difference and fine silver wire could be an improvement there.

Also, feet for isolation, easy upgrade and reduces micorphonics somewhat.

I cannot tell what type of trannys those are but, this is where a major difference in sound quality is made IMHO, especially the output types. This change can be expensive and goes beyond the $550 you spent for the amp.

Rolling vacuum tubes is part of owning an amp of this type and part of the fun. So you might try different types of tubes, new, nos, ect.

I believe CK spent over $1000.00 for his project and I spent $2500.00 on mine.

All in all, you get what you pay for, but is it worth it ?
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Old 26th February 2003, 03:03 PM   #17
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Hey Magnetmaz,

Can you tell what the output iron is? It doesn't look like Hammond or Magnequest, or One Electrons for that matter. They are between 100 and 150 apiece. This will tell how much was actually paid for the components versus how much you are getting as "worth".

First off the construction looks very good, so in my opinion that is worth the cost right off. I do not believe he took more than 5 or 6 hours on it. (Sorry fdegrove, but it takes me 5-6 hours to punch 9 tube socket holes and three transformer holes, not to mention the inputs and outputs in steel. This chassis looks like aluminum. It takes me about 2/3rds the time in aluminum.)

But if he got the transformers from Hand Made Transformers, he only paid about 50 bucks apiece. I personally do not know how good they are.

Otherwise, $550 is not bad. Construction underneath also looks very good.

My 2 cents.
Gabe
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Old 26th February 2003, 03:53 PM   #18
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pretty sure the Trafos are hand made. The choke especially has a weird glue-looking brown hardened goo on the laminates. I won't know how they sound for a couple days....but it feels like i am starting from the bare minimum components, and will upgrade as i have money.

The chassis is steel...probably a hammond chassis...riveted on the corners.

I agree with Maybeim..the caps and the connectors will be the first thing i upgrade.

There are rubber feet on the bottom plate of the chassis.

-Maz
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Old 26th February 2003, 05:31 PM   #19
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Just got an email from the guy who sold it to me. I asked who made the trafos, and what type of cap the big orange block was.


his answers :
the orange cap is 15uf 400volts ac its polyprolyne in oil, we wind our own
transformers those are 3400 ohm to 4,8,16 ohm , with a 98% bobbin fill ,
15hz- 45khz 15 watt power rating,
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Old 26th February 2003, 07:36 PM   #20
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Hi Magnetmaz,

I wonder if it is from Handwound. Interesting. He's making a wee bit more than 150 bucks off of you.

As for the chassis... if it is Hammond it will be aluminum. Unless he took the trouble of blasting off the grey primer, or black matte paints the steel ones come in.

Since you say it is rivoted in the corners (not welded?) then it must be manufactured from some other source.

Still... it is nice.

Gabe
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