Author Topic: Rogers Cadet Clone project  (Read 1216 times)

Offline Mars

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Rogers Cadet Clone project
« on: November 21, 2016, 06:30:19 AM »
Hi All

Last year Akomeogi built a DIY clone of the Rogers Cadet III amplifier. I planned to do another clone sometime since, and it got completed last week.

This time I integrated a phono preamp into the build. I chose the RCA design and it turned out well.

Amplifier specifications

  • ECL86 output tubes
  • two ECC83 phono preamp
  • 10 watts per channel into 4 or 8 ohms
  • C-core output transformers
  • point to point wiring
  • switcheable line level/phono input selection

The amplifier sounds stunning. It was tested on a set of Tannoy speakers, and the report was very positive :groovy:

« Last Edit: February 17, 2017, 05:09:24 PM by Curlycat »
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Offline Mars

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Re: Rogers Cadet Clone project
« Reply #1 on: November 21, 2016, 11:53:31 PM »
Actually went fot Imgur so I can upload from my Adroid phone. Let's see how it goes:



Is the little wonder visible?     :thinking:
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Offline Mars

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Re: Rogers Cadet Clone project
« Reply #2 on: November 22, 2016, 12:00:06 AM »
Rear view:

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Offline Mars

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Re: Rogers Cadet Clone project
« Reply #3 on: November 22, 2016, 12:01:46 AM »
The work horses

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Offline Family_Dog

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Re: Rogers Cadet Clone project
« Reply #4 on: November 22, 2016, 06:43:13 AM »
Karel, where did you source the ECL86 valves? I've been looking for some and gave up, used ECL82 instead.


-F_D



-Eric

That Guy in South Africa...
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Offline charles

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Re: Rogers Cadet Clone project
« Reply #5 on: November 22, 2016, 07:02:16 AM »
Dear Family_Dog

Please PM me, I have some ECL 86 valves available.

Offline Akomeogi

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Re: Rogers Cadet Clone project
« Reply #6 on: November 22, 2016, 05:34:47 PM »
That looks strangely familiar! - wonder why....? Deja-vu...

Seriously though Karel, I was wondering when this was going to happen. You must pop around for a visit and then we can compare (i also believe we still have business to conclude?).

What made you decide to only go with two tubes on the preamp?

Have you spent any more effort on the Akai?

Looks cool though.... Love the idea of being able to switch between phono & line....

Regards
Durbanville Rocks!

Offline Qualityten

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Re: Rogers Cadet Clone project
« Reply #7 on: November 24, 2016, 12:55:23 AM »
Beautiful work.  I've just starting trying ECL86s and like the sound very much.  Have you ever thought of using PCL86s instead with a different heater transformer, on grounds of cost?

Offline Akomeogi

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Re: Rogers Cadet Clone project
« Reply #8 on: November 24, 2016, 10:27:17 AM »
Hi Qualityten

I can confirm that Karel and I at one stage considered using the PCL86 in my build, but my objective was to build a true copy of the original, from voltage doubler circuitry (with the correct, scarce diodes), ECL86s in the power amp and the very scarce (and expensive) ECC807's in the preamp.

Luckilly, a number of fellow forum Samaritans stepped up to the plate and I was able to procure some NOS ECL86s! I can't thank them enough....

However, I am planning another build in future using the PCL86s and the ECC83s (12AX7), where the heater voltages that can be used are closer to each other (between 12v & 14.5v). As a matter of fact Karel is busy putting together the power transformer to this specification for me already. I also already have NOS stock of the valves required to do this.

At the moment I am considering doing this as a split configuration (i.e. not an integrated), with separate:
* Power supply
* Power amp monoblocks
* Preamp

Should be an interesting exercise.

Regards


 
Durbanville Rocks!

Online gavinbirss

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Re: Rogers Cadet Clone project
« Reply #9 on: November 24, 2016, 10:32:25 AM »
@Akomeogi,

Was lucky enough also to buy some ECL86's from Charles to try in a Elekit 8100



Quote
future using the PCL86s and the ECC83s (12AX7),
Hang on the PCL86 is a EL84 with ECC83? Why talk about another ECC83?

See you want to switch between phonostage and line input...

« Last Edit: November 24, 2016, 10:52:54 AM by gavinbirss »

Offline Qualityten

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Re: Rogers Cadet Clone project
« Reply #10 on: November 24, 2016, 07:54:32 PM »
Akomeogi, thanks for the info.  I'm impressed at your use of (and access to) the ECC807s.  Scarcer than rocking horse droppings. Those transformers wound by Karel look superb.

I hope you'll post pics of the new build too in due course.

Regards.