My old friend Dremel has shaved of everything not essential so it fits.
But it´s a struggle to assemble/dissasemble.
Lesson learned always use a box twice the size you first estimate
It´s about time it starts glowing and stop resisting !!!!!!!
Murres law says Murphy was a damn optimist !!!!!
But it´s a struggle to assemble/dissasemble.
Lesson learned always use a box twice the size you first estimate
It´s about time it starts glowing and stop resisting !!!!!!!
Murres law says Murphy was a damn optimist !!!!!
Just for fun,
I grabbed the mobile phone and thought you might like to hear (such as the phones mic is) my 1.5 Watt per channel..LOL
Just put The amp and speakers in a corner and took the video..... speakers are Alpair7 4ohm
OTL 6C33C power amp 1 - YouTube
Then with the Deamau5 bass<<the mic on the phone does not pick it up well!
6C33C OTL power amp running two heaters on OP tubes.. - YouTube
All just for fun..
Regards
M. Gregg
I grabbed the mobile phone and thought you might like to hear (such as the phones mic is) my 1.5 Watt per channel..LOL
Just put The amp and speakers in a corner and took the video..... speakers are Alpair7 4ohm
OTL 6C33C power amp 1 - YouTube
Then with the Deamau5 bass<<the mic on the phone does not pick it up well!
6C33C OTL power amp running two heaters on OP tubes.. - YouTube
All just for fun..
Regards
M. Gregg
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Theres something very different with your amp and mine.
Lets see:
Yours: have a nice chassi high waf and plays
Mine: recycled PSU box in two pieces upside down on workbench stonedead
WANT TO TRADE
The phone seems to attenuate the bass I don't know why ...
Err I think I will keep it.. I have a few things I want to try..
LOL You know the room is dead when it's turned off, it's strange
Well when is yours going to be playing then?
LOL,
I have been told by my other half...LOL
Where are the vocals and I have to have a handbag bear on the speaker..
So here is the last video..<<under duress..
6C33c OTL amp 3 - YouTube
I would have recorded some jazz but there you go...
Last one ....
Regards
M. Gregg
I have been told by my other half...LOL
Where are the vocals and I have to have a handbag bear on the speaker..
So here is the last video..<<under duress..
6C33c OTL amp 3 - YouTube
I would have recorded some jazz but there you go...
Last one ....
Regards
M. Gregg
Weekend coming to its end.
Murre against OTL 1-2
New tubes in everything fired up 6C33 running good.
Music playing.
Then it strikes again !!!!!
OSCILATION !!!!!!!!!
Then one side dead other side sounds like crap.
Probably my cheapskate choice of gridstoppers that struck back and killed the sand in one channel.
I´ll order a new set of IRF 710 and take the time to find some descent CC resistors.
Now its getting personal the amp is winning all the battles, time for me to win the war !!!!
Murre against OTL 1-2
New tubes in everything fired up 6C33 running good.
Music playing.
Then it strikes again !!!!!
OSCILATION !!!!!!!!!
Then one side dead other side sounds like crap.
Probably my cheapskate choice of gridstoppers that struck back and killed the sand in one channel.
I´ll order a new set of IRF 710 and take the time to find some descent CC resistors.
Now its getting personal the amp is winning all the battles, time for me to win the war !!!!
I am wondering,
Are you sure that nothing is touching / shorting when the amp is assembled?
Perhaps between the top and bottom sections?
OTL
Its strange because you had the pre/ PI section up and running and there should be no additional load because of the caps from the PI...
I would run the sections separately and check all voltages on the dividers for the CCS..
Just the schematic again..
I used one divider and cap for all CCS with four 4.7M coming from it, one to each CCS...R9 changed from 470K to 10K. On my amp C2 is changed from 100n to 220n between 1st CCS and 2nd stage. PI resistors changed to 47K. C4 C3 caps to 6C33C grids are 470n. Everthing else is the same.
The only other thing I can think of is I used 1200V HV resistors for the 4.7M..
Regards
M. Gregg
Are you sure that nothing is touching / shorting when the amp is assembled?
Perhaps between the top and bottom sections?
OTL Its strange because you had the pre/ PI section up and running and there should be no additional load because of the caps from the PI...
I would run the sections separately and check all voltages on the dividers for the CCS..
Just the schematic again..
I used one divider and cap for all CCS with four 4.7M coming from it, one to each CCS...R9 changed from 470K to 10K. On my amp C2 is changed from 100n to 220n between 1st CCS and 2nd stage. PI resistors changed to 47K. C4 C3 caps to 6C33C grids are 470n. Everthing else is the same.
The only other thing I can think of is I used 1200V HV resistors for the 4.7M..
Regards
M. Gregg
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Regards the CC resistors.
My amp ran quite well with 500V 1W working 1K MF in first stage CCS and 270 Ohm CF in the second stage....
What off set voltage had you got across the speaker?
Just for interest the 6c33C's don't sound at their best for about 30min...and they take about 3 weeks to burn in sound changing all the time (getting better)..
How good is the Gnd between the presection and the supply...NB I have the pre Gnd and speaker Gnd at the capacitor OV connection direct on with a thick wire to earth...
Its strange that the PI return is in the OV rail between the OP tubes<<<psudo not cap Gnd...
Regards
M. Gregg
My amp ran quite well with 500V 1W working 1K MF in first stage CCS and 270 Ohm CF in the second stage....
What off set voltage had you got across the speaker?
Just for interest the 6c33C's don't sound at their best for about 30min...and they take about 3 weeks to burn in sound changing all the time (getting better)..
How good is the Gnd between the presection and the supply...NB I have the pre Gnd and speaker Gnd at the capacitor OV connection direct on with a thick wire to earth...
Its strange that the PI return is in the OV rail between the OP tubes<<<psudo not cap Gnd...
Regards
M. Gregg
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Must confess i let electrons flow a little faster with B+ at 190/360v
Measuring told me sand still there, one 6j5 stone dead
How the .... did i manage to kill that 6J5.
Reason for oscilation must be combination of Low voltage resistors, higher B+.
Have to check the resistors to see if they still alive.
Will put in higher value and good quality gridstoppers and then see how low i can go before it runs away on me.
Measuring told me sand still there, one 6j5 stone dead
How the .... did i manage to kill that 6J5.
Reason for oscilation must be combination of Low voltage resistors, higher B+.
Have to check the resistors to see if they still alive.
Will put in higher value and good quality gridstoppers and then see how low i can go before it runs away on me.
Does your PI go to the mid point of the OP tubes and not to Gnd?
The resistors for the PI need to be 2W or more...
Regards
M. Gregg
One 6j5 is stone dead.
What came first, death of tube or oscillation/resistor arcover is to be investigated.
I have:
Gate stoppers 1K MF ferrit/270 CF ferrit
Gridstopper on PI 10K CF.
PI 47K 2watt and neon...
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