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 Post subject: 845 amp project
PostPosted: 04 Mar 2015, 20:06 
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Joined: 15 Nov 2013, 10:16
Posts: 240
Location: MB, Canada
So.. Over the past few months I've been doing a lot of research on an 845 amp design that I can tackle. Still working on a few things with the design, but when I have a completed schematic I'll post it here.

It's still the early stages, but I have been collecting parts, and I'll be posting in this thread as the build progresses.. It'll be a long while..
So I happened to order some 845 tubes from a reputable seller on ebay, anyways they arrived and I'm concerned about one of them. The plate seems to be loose in one of the tubes. Here's a video https://drive.google.com/folderview?id=0B_8mD0hS_1d_VWo1eVJiSlloN2s&usp=sharing that shows what I'm talking about.

I'm assuming this isn't good.. I've contacted the seller to see what they can do about it, but just thought I'd post about it in case this isn't such a big deal.

What do you guys think?


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 Post subject: Re: 845 amp project
PostPosted: 04 Mar 2015, 20:50 
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Joined: 06 Apr 2009, 10:08
Posts: 1592
Location: US Pacific Northwest
This is a bad tube with a serious manufacturing defect. The plate was not properly welded to the supports. Return the tube immediately.

I am at a loss for how such a tube would pass initial ATP. You said "reputable seller". Are you totally sure the seller is not selling factory rejects. This is a very common practice in the counterfeit devices market.

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 Post subject: Re: 845 amp project
PostPosted: 04 Mar 2015, 21:05 
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Joined: 15 Nov 2013, 10:16
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Location: MB, Canada
Suncalc wrote:
This is a bad tube with a serious manufacturing defect. The plate was not properly welded to the supports. Return the tube immediately.

I am at a loss for how such a tube would pass initial ATP. You said "reputable seller". Are you totally sure the seller is not selling factory rejects. This is a very common practice in the counterfeit devices market.


They have a good ebay reputation. 475 positive feedback messages and 4 negative in the past year.

I suppose I don't know that they're not factory rejects for sure, but they're listed as "New: A brand-new, unused, unopened, undamaged item in its original packaging". I've emailed them to see what they say because they make a note of stating in their ad's that they'll work with buyers to resolve any issues.


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 Post subject: Re: 845 amp project
PostPosted: 04 Mar 2015, 23:10 
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Joined: 13 Feb 2013, 11:02
Posts: 47
Location: Canada
I'm not a fan of buying tubes from Ebay unless there is absolutely no choice. I prefer to use known reputable tube dealers like The Tubestore.
I hope you can send it back.
Do not use it.

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 Post subject: Re: 845 amp project
PostPosted: 04 Mar 2015, 23:18 
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Joined: 15 Nov 2013, 10:16
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Location: MB, Canada
blackdog wrote:
I'm not a fan of buying tubes from Ebay unless there is absolutely no choice. I prefer to use known reputable tube dealers like The Tubestore.
I hope you can send it back.
Do not use it.


Yea, I'll see if I can just do a refund and send them back.. Lesson learned.


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 Post subject: Re: 845 amp project
PostPosted: 05 Mar 2015, 02:41 
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Joined: 08 Aug 2009, 03:11
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Location: Chilliwack, BC
It may not have been him. There's some pretty nasty gorillas working in shipping tubes :nuke:

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 Post subject: Re: 845 amp project
PostPosted: 05 Mar 2015, 09:10 
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Joined: 15 Nov 2013, 10:16
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Location: MB, Canada
Geek wrote:
It may not have been him. There's some pretty nasty gorillas working in shipping tubes :nuke:


True enough. In any case He'll do a refund for me when I ship them back.


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 Post subject: Re: 845 amp project
PostPosted: 05 Mar 2015, 21:21 
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Joined: 06 Apr 2009, 10:08
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Location: US Pacific Northwest
Well, I don't know what you paid the E-Bay guy, but 845s are listed as $446.45 at the AES website, i.e. http://www.tubesandmore.com, ["OUCH" :eek: ] but are only $99.95 at TubeDepot. So you do have options.

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 Post subject: Re: 845 amp project
PostPosted: 05 Mar 2015, 22:12 
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Joined: 08 Aug 2009, 03:11
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Location: Chilliwack, BC
Hundred bucks from Jon, as well:
http://www.thetubestore.com/Tubes/845-T ... uguang-845

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 Post subject: Re: 845 amp project
PostPosted: 05 Mar 2015, 23:47 
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Joined: 15 Nov 2013, 10:16
Posts: 240
Location: MB, Canada
Geek wrote:


Yea, I'm planning to go with those ones from thetubestore.com I think.

I think that 845 for sale at AES is old stock, American made.. They're pretty much gold these days. But the Chinese ones are supposed to be pretty good. I talked to Jon at thetubestore, and he said that the quality control on the Shuguang ones is generally quite good, but he said because of the weight of the plate assembly, it's not unheard of for something to break during shipping, especially when travelling all the way over here from China.


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