2nd Generation 50w Period Correct ODS

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talbany
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2nd Generation 50w Period Correct ODS

Post by talbany »

Tony

Here is a Layout of a period correct 2nd Generation ODS 50W specimen,complete with part numbers for cap types, resistor types, type coax with specs, FET # for cross referencing and other valuable info.. However the source of this info and the series # of this amp and its whereabouts etc must be kept confidential due to request, so don't ask for pictures, Schematics or relevant information pertaining to this particular amp here or in a PM..Thank You!!
This is more than enough info to build a wonderful sounding 2nd generation ODS with all correct specs..Good Luck!!

For the sake of accuracy & confusion I recommend we refrain from calling this a so called 70's amp since we now have the info.. (we don't call 124 an 80's amp) same applys here, it's simply a 2nd generation ODS..
To Clarify
2nd generation "pre-classic" tone stack (1975 – 1978):

Treble: 500KL pot / 510pF treble cap
100k slope resistor
Mid: 250KA pot / .01 mid cap
Bass: 1MA pot / .1 bass cap / .002 soldered between the terminals 2 and 3 of the bass pot and .02 cap soldered between terminals 1 and 2 of the bass pot / 10K tail
Also notice cap types are not the same throughout

Someone who wants something like the "Running On Empty" slide tone should start with a 2nd generation ODS clone (your new layout)


Here you will find some clips(posted by MAX) that have been recorded with such a 2nd generation "pre-classic" ODS 50W in different threads here. Here are the links to these posts:
http://ampgarage.com/forum/viewtopic.ph ... 483#136483
http://ampgarage.com/forum/viewtopic.ph ... 484#136484
http://ampgarage.com/forum/viewtopic.ph ... 960#133960
http://ampgarage.com/forum/viewtopic.ph ... 973#134973
http://ampgarage.com/forum/viewtopic.ph ... 368#129368


Also attached are pictures of #40 to help w/Lead dress and other references pertaining to layout..
These really are WONDERFUL sounding amps and recommend them highly!!

Tony

Here you find clips of all the ODS generations from David Lindley's 1st generation ODS up to the skyline-HRM amps in the #200+ range: http://ampgarage.com/forum/viewtopic.ph ... 06&start=0
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Last edited by talbany on Fri Sep 07, 2012 4:23 pm, edited 5 times in total.
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talbany
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Re: 2nd Generation 50w Period Correct ODS

Post by talbany »

More #40 Pics
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" The psychics on my bench is the same as Dumble'"
marcos
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Re: 2nd Generation 50w Period Correct ODS

Post by marcos »

Here´s a picture from a stock 2nd generation amp.
The ceramic cap in the James configuration reads 3.3 nF.
So far I know of three variations for this cap, 2 nF, 3.3 nF and 5
nF. Only matters when in Jazz mode, the cap is shorted in Rock mode.
Just another small detail
Marcos
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talbany
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Re: 2nd Generation 50w Period Correct ODS

Post by talbany »

Marcos
Thanks for the info and pic..Always helpful :)

Tony
waynard
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Awesome!

Post by waynard »

Great pics and layout diagram! Thank you!
far out solid and right on
vibratoking
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Re: 2nd Generation 50w Period Correct ODS

Post by vibratoking »

In the layout, shouldn't the wiper of the treble pot be connected to the right outer leg of the volume pot?
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danotron
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Re: 2nd Generation 50w Period Correct ODS

Post by danotron »

Is there schematic to go with this layout?
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Ruslan
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Re: 2nd Generation 50w Period Correct ODS

Post by Ruslan »

hi i am not to understand how the chassis is attached
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M Fowler
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Re: 2nd Generation 50w Period Correct ODS

Post by M Fowler »

On the outside end of the chassis.
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AtomCap
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re

Post by AtomCap »

4 qty 12A** tubes???
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erwin_ve
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Re: 2nd Generation 50w Period Correct ODS

Post by erwin_ve »

This one popped up on march the 26th 2018 on Reverb.
Description:
Dumble Overdrive Special Combo
1977 ( Caps / Components Dated 77)
Silver face
Sno 003X
50 Watt
1+12 ( Altec )
Grey / Brown Suede
Export Voltage Selector to rear
Condition 10/10 ( This is one the best / finest Silver Face Amplifiers Combo amplifiers as al is 100% untouched )
Original Valves / Tubes ( Ie HD installed in 1978 - 1979 )

History - The amplifier has been purchased from the family of original owner whom only used for home / studio purposes.
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erwin_ve
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Re: 2nd Generation 50w Period Correct ODS

Post by erwin_ve »

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erwin_ve
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Re: 2nd Generation 50w Period Correct ODS

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martin manning
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Re: 2nd Generation 50w Period Correct ODS

Post by martin manning »

Alternate modern OD relay for 2nd Gen builders.
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Mr. dB
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Re: 2nd Generation 50w Period Correct ODS

Post by Mr. dB »

Image

Does this layout of components on the controls match up to any of the known layouts?
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