How are the batteries holding up? And what is your club car battery tray made out of (underneath your seat)? My club car only has metal bars down there but I’d love more of a floor to block water and such
@mikedski9698Күн бұрын
LAST STARFIGHTER 40TH ANNIVERSARY 1984-2024!
@peterpiets36315 күн бұрын
1984😊
@georgegherghinescu9 күн бұрын
Hello love the tube amp videos, so educational and easy to follow @ 19:31 I would speculate that the aparent lower power compression below 1k has to do with the distortion behaviour of the output transformer. Looking at the distortion plots there is increased distortion below 1k, I would argue the core is saturating and the aparent lack of compression measured is the rise in distortion where the core is active (<2k). I am by no means an expert and could likely be very wrong :)
@Edgarbopp9 күн бұрын
Very possible
@louco217 күн бұрын
What are you looking at to decide distortion is becoming wonky? Thank you
@louco217 күн бұрын
Thank you for taking the time to do this video!
@ericrawson290918 күн бұрын
It's not just variations in current drawn from the supply that cause reservoir cap voltage to vary. Here in South West England, my mains supply voltage varies a few percent with a regular pattern to it. It's like two or three simultaneous things varying the voltage, each having a different frequency in the range one to three Hz. If you concentrate you can see brightness fluctuations in an incandescent lamp, and also hear the same variations in the magnetostriction hum of a large transformer.
@NAB62219 күн бұрын
Having just watched the movie, this barely even resembles it. They completely cut Harry and Alex, the destruction of the Palomino, Kate's near-lobotomy, and removed any personality from the cast. Oh, and the scene with the meteor chasing the crew across the bridge was mirrored. I know they had very little run time on the record, but yikes! I grew up with this record, but wow, it's very very inaccurate. 😂 Edit: Thanks for uploading, I'm glad I could hear this again!
@miouno26 күн бұрын
Bravo bravo bravo
@rugrat51126 күн бұрын
Must be nice I have one rn I've had since I was like 8
@audiofreqАй бұрын
Doug has helped me find my mystery transformer primary and secondary pins, identified correctly. Amazing teacher!
@MarkErikEEАй бұрын
Good explanation of the different supply options. How does this final circuit differ from "capacitance multiplier? To my untrained eye it does not. I'll try the last one out. Is it necessary to filter it further with an inductor or can I pass it straight to plate?
@EdgarboppАй бұрын
The final circuit has a voltage reference created by a shunt regulator. In this case it’s a resistance and a Zener. That locks the MOSFET gate at a specific voltage. So it’s more like a regulator than a capacitance multiplier at that point. The output may feed the output tube plates directly. It will be very well filtered
@MarkErikEEАй бұрын
@@Edgarbopp Thanks for explanation. Can I use high voltage NPN silicon transistor instead of a MOSFET? There are also 150v and 200v zeners available - how do I set the voltage for the transistor with it? I need like 250V in the output with up to 100 mA of current.
@EdgarboppАй бұрын
@@MarkErikEE a BJT can be used but the base will require current unlike a mosfet. To generate your reference voltage you will need to create a shunt regulator with a resistor and a Zener or a string of zeners. You will need to supply a minimum current to the Zener for it to drop its specified voltage. That should be in the data sheet. Chose the the resistance by understanding that the remaining input voltage that is not dropped by the zeners will be dropped by the resistance.
@andidubya3840Ай бұрын
I keep coming back to this as it's one of the best explanations of this circuit in a practical application that I know of. However MOSFET pass device that R4 needs a better explanation. Am I right in R4 drops more than 6.4v then that's current limiting?
@EdgarboppАй бұрын
Yes, that’s my understanding though I don’t think it’s really any protection from a short so it’s perhaps of limited value.
@kft590Ай бұрын
This is a series Voltage Regulator versus a Shunt Regulator, many prefer a voltage source feeding a Shunt Regulator for Audio Electronics as it is more stable to powers line fluctuations. A Shunt Regulator would have the Drain going to ground and the Source near the incoming voltage..
@paulhetherington3854Ай бұрын
My wife, and I, studied: "REACTANT PHYS -- UCSD -- CURRICULUM - there be -- none of this!" Youngya -- + De -- + Doug <<< named by - the Muse
@paulhetherington3854Ай бұрын
He used, the Muse -- intel -- i.e. gov? And he'll deny, he be -- Muse! Unifique - Muse -- Constitutional -- ownership -- of US school!
@paulhetherington3854Ай бұрын
/loch dn tn grd2''x~tmp fs rcvr + gml cmd fon td/ /2''vf(xF'~tmp dn tn)< fs u 8''frch 2''UI' td chn < vd LN'' kntrolz/ /4'p''~dn tn < tstx i.e. ~tmp cmd < gml abv kol stachon/ /~vaar fr grd2''x < contnt i.e. gml cmd fon < txt bx || td unit/ /Tvf(xgrd2''~tmp fs 2'' inch kf'' grdz < z''X'k' pn gml cmd LN'' fon td)/ /O 2'' smultz inch kf'' grdx rul~tmp thrm 2''vkRx rvcr i.e. paavlow + stapach vaakuum/
@ColocasiaCorm2 ай бұрын
Great video. Thanks
@stevekudlacek2 ай бұрын
What specific Oscilliscope do you use? And do you recommend a specific non-DIY tone generator?
@Edgarbopp2 ай бұрын
It’s just an inexpensive Hantek and works very well. The signal gen is also a cheap unit from AliExpress. Honestly anything decent will be ok, we’re just doing audio frequency work after all.
@bigboypants9882 ай бұрын
Guitar smp builders look elsewhere. The main subject is not used
@detlefkoertge69882 ай бұрын
One of the best explanations of load lines and the effect on amplification I've seen in years! Thank you for posting this.
@chbloss2 ай бұрын
"Let's begin nowwww..."
@JAYDELROSARIQ2 ай бұрын
Drawing never work Illusion... physical activity materials piesa purtyxhQn then your jvy tools
@alexnovique17182 ай бұрын
Awesome 👍👌
@ARASHMAFI12 ай бұрын
This is genius! You guys deserve a patent for this !
@ARASHMAFI12 ай бұрын
lol this comment was meant to go to the block g distortion bug bias video
@alnicospeaker3 ай бұрын
You make these "cheap" russian tubes work for hifi, fantastic! For negative bias Voltage I often use a small 1" by 1" print trafo 230V/9V and hook it up the the 6,3V ac heater winding (or to mains and use a voltage doubling bridge depending on -V needs). My local supplier has these small trafos for 0,95€ and they're light and small enough to be placed under the chassis.
@alnicospeaker3 ай бұрын
Nice circuit! I especially like the power supply. Most people either use no MOSFETs at all or go crazy with super complicated transistor circuits. I just checked and the FQP10N60C is very affordable and available.These should also work as mosfet followers in the signal chain. Some ideas: No input transformer and use a 6N2P with higher gain for preamp tubes, Ra 120k with Va about 200V should give nice swing. And add the CCS tail could to your -22V supply. 6H8C only has a datasheet-µ of 21,5 , real life v/v of maybe 15.. Do you think this will work well with a 6N2P/12ATX or does the GU17 need the beefier driver with more current capability?
@Edgarbopp3 ай бұрын
Hard to say until you give it a try. Those little input transformers are inexpensive and available on AliExpress though. In regards to the 10N60c I’ve actually just designed a A2 cascode output stage amp that uses one to drive the cathode of the output tube! When I get it finished up I’ll make a video about it. It’s 10wpc with a single el34 per channel SE.
@alnicospeaker3 ай бұрын
@@Edgarbopp I might just do that - I have all tubes and parts on hand..Regarding the sand-assisted cathode drive, yes I have read about it on diyaudio. Looking forward to that video as I have experimented with a screen-grid driven 6P45S SE amp (I have nice unused op-iron for it) during covid but struggled to get the driver right and it sits unfinished
@georgegherghinescu3 ай бұрын
Love your educational videos especially this one and the load lines one! Very easy to follow and understand. Regarding transformers, output ones, I am looking at trying a 5k:5ohm LL1682 but my speakers are 8ohm, was wondering what problems would that cause like maybe bandwith issues. Need a good 10k:8ohm in my circuit but 8k would work. My output tubes are 6p1p in push pull A class. Thank you for posting all this great stuff and looking forward to new affordable tube discoveries and projects. PS: Russian 6H7C are very cheap preamp tubes with good linearity and paraleled are capable to drive interstage trafos, could be an affordable alternative to 6SN7 with a little less gain. They where intended for class B output stages. George.
@Edgarbopp3 ай бұрын
I’ve had very good luck with the 6H8C too.
@engelashley47603 ай бұрын
What pa are you using
@Edgarbopp3 ай бұрын
Union PA. Random parts with WWR. Jet pack torso.
@Mr.ZarganaHunter3 ай бұрын
31
@tesla14313 ай бұрын
if I wanted to calculate the output power that the amplifier provides before switching to class B, how can I do it? that is, I want to know the power only in class A. thanks
@munja21113 ай бұрын
Great tutorial, thank you
@Edgarbopp3 ай бұрын
Happy to help
@camzoutdooradventure28243 ай бұрын
Did you bypass the obc? Or just hook them up to original positive and negitive cables?
@anotherasmrchannel78163 ай бұрын
nice video thanks, a doubt arises at minute 36, if the supply voltage is 360v how does the signal oscillate up to 520?
@Edgarbopp3 ай бұрын
Good question! Because the output transformer is an inductor it has a reactance not a resistance. It supplies the voltage above supply. Inductors supply voltage to preserve current. They’re a type of current source.
@anotherasmrchannel78163 ай бұрын
@@Edgarbopp That's incredibile, so when the tube oscillates in class A, before the cut-off at the bottom, it always reaches that extra voltage? Thanks for these clarifications
@audiofreq3 ай бұрын
I have 2 transformers that do not have markings or data sheet. Only a schematic of where it belongs. Do you mind if I email you some questions to help identify the pins of primary/secondary? Thank you.
@steveswartz18753 ай бұрын
Just wanted to say I enjoyed this video. I already have a OTL amp based on this tube (16 of them!). Hope you give some detail about the output tranformer. Not sure what EM label near mosfet signifies. Does it mean encasement mode?
@Edgarbopp3 ай бұрын
Enhancement mode. The output transformers I purchased on AliExpress. I can find the listing for them if you want. Glad you enjoyed the video.
@audiofreq3 ай бұрын
I had to subscribe. I like your calm demeanor and straight forward informative approach! Thank you
@Edgarbopp3 ай бұрын
Very nice of you to say.
@RCThis3 ай бұрын
You are awesome bro!!! Thanks!!! How are they holding up??
@tony_potsandpans3 ай бұрын
Dude, do everyone (including yourself) a favor and write a script. Its really hard to watch and understand your videos with all the "uuhh" and "uuummm" in that monotone. The content is cool, the execution is rough.
@Edgarbopp3 ай бұрын
Please feel free to not consume my content.
@peterpowder85463 ай бұрын
I had one in late 60’s. Loved it
@tomekichiyamamoto21773 ай бұрын
Why did you use an RCA instead of a XLR?
@Edgarbopp3 ай бұрын
My sound card has a unbalanced input
@qitstrn3 ай бұрын
I have Epoch. I was considering big battery also. Very similar kit. I bought the 60ah kit and like you mentioned it wasn’t enough. I had to upgrade a d buy one more battery to bring me to 90ah. The epoch is a nice kit
@jonadabster84014 ай бұрын
I have repaired mine a couple times in 20 years . No longer able . any replacement speakers that would be ok ? Do they need to be 4 ohm ?
@neccron99564 ай бұрын
What about negative feedback to make it regulated?
@63worldseries4 ай бұрын
where the hell is June?
@haiangtran20364 ай бұрын
Wow 😂 I just tell the high output impedance source alter my headphone very much and no reverb 😂 I can't see the reverb more effect when damping factoe is low, just frequency response. With my own, the bass is more deep and the sound signature is warmer or duller 😂.
@hpfctif7tx7t4 ай бұрын
Can you make a same tutorial for biasing otl amps? cuz I just built one recently and I wanna tune it to sound good because it sounds very bad right now😂 my tubes are 6h8c and 6l6gc my setup is self biasing but I think I think I messed up with my resistor values on the cathode
@michaeld96824 ай бұрын
I found this helpful how you test transformers
@emazonreviews62695 ай бұрын
OMG!!! I listened to and read this for years!! Thanks sooo much for the upload
@steves74585 ай бұрын
Hi Doug. I have the same kit. Does your battery display on the batteries stay on all the time. Mine does and it does worry me.
@Edgarbopp5 ай бұрын
It does, though it doesn’t worry me. The draw from the led is probably an order of magnitude less than the leakage current of the battery cells themselves.
@steves74585 ай бұрын
@@Edgarbopp Thanks doug. How about the breaker. Do you shut them off and just leave it on. Seems like a good battery. Much better then lead acid.
@Edgarbopp5 ай бұрын
@@steves7458I’d hate to wear out that breaker by using it as a on off switch. I leave them on.
@donaldfennell9715 ай бұрын
You can power the meter by getting the 48v from the key switch on terminal@@Edgarbopp
Пікірлер
How are the batteries holding up? And what is your club car battery tray made out of (underneath your seat)? My club car only has metal bars down there but I’d love more of a floor to block water and such
LAST STARFIGHTER 40TH ANNIVERSARY 1984-2024!
1984😊
Hello love the tube amp videos, so educational and easy to follow @ 19:31 I would speculate that the aparent lower power compression below 1k has to do with the distortion behaviour of the output transformer. Looking at the distortion plots there is increased distortion below 1k, I would argue the core is saturating and the aparent lack of compression measured is the rise in distortion where the core is active (<2k). I am by no means an expert and could likely be very wrong :)
Very possible
What are you looking at to decide distortion is becoming wonky? Thank you
Thank you for taking the time to do this video!
It's not just variations in current drawn from the supply that cause reservoir cap voltage to vary. Here in South West England, my mains supply voltage varies a few percent with a regular pattern to it. It's like two or three simultaneous things varying the voltage, each having a different frequency in the range one to three Hz. If you concentrate you can see brightness fluctuations in an incandescent lamp, and also hear the same variations in the magnetostriction hum of a large transformer.
Having just watched the movie, this barely even resembles it. They completely cut Harry and Alex, the destruction of the Palomino, Kate's near-lobotomy, and removed any personality from the cast. Oh, and the scene with the meteor chasing the crew across the bridge was mirrored. I know they had very little run time on the record, but yikes! I grew up with this record, but wow, it's very very inaccurate. 😂 Edit: Thanks for uploading, I'm glad I could hear this again!
Bravo bravo bravo
Must be nice I have one rn I've had since I was like 8
Doug has helped me find my mystery transformer primary and secondary pins, identified correctly. Amazing teacher!
Good explanation of the different supply options. How does this final circuit differ from "capacitance multiplier? To my untrained eye it does not. I'll try the last one out. Is it necessary to filter it further with an inductor or can I pass it straight to plate?
The final circuit has a voltage reference created by a shunt regulator. In this case it’s a resistance and a Zener. That locks the MOSFET gate at a specific voltage. So it’s more like a regulator than a capacitance multiplier at that point. The output may feed the output tube plates directly. It will be very well filtered
@@Edgarbopp Thanks for explanation. Can I use high voltage NPN silicon transistor instead of a MOSFET? There are also 150v and 200v zeners available - how do I set the voltage for the transistor with it? I need like 250V in the output with up to 100 mA of current.
@@MarkErikEE a BJT can be used but the base will require current unlike a mosfet. To generate your reference voltage you will need to create a shunt regulator with a resistor and a Zener or a string of zeners. You will need to supply a minimum current to the Zener for it to drop its specified voltage. That should be in the data sheet. Chose the the resistance by understanding that the remaining input voltage that is not dropped by the zeners will be dropped by the resistance.
I keep coming back to this as it's one of the best explanations of this circuit in a practical application that I know of. However MOSFET pass device that R4 needs a better explanation. Am I right in R4 drops more than 6.4v then that's current limiting?
Yes, that’s my understanding though I don’t think it’s really any protection from a short so it’s perhaps of limited value.
This is a series Voltage Regulator versus a Shunt Regulator, many prefer a voltage source feeding a Shunt Regulator for Audio Electronics as it is more stable to powers line fluctuations. A Shunt Regulator would have the Drain going to ground and the Source near the incoming voltage..
My wife, and I, studied: "REACTANT PHYS -- UCSD -- CURRICULUM - there be -- none of this!" Youngya -- + De -- + Doug <<< named by - the Muse
He used, the Muse -- intel -- i.e. gov? And he'll deny, he be -- Muse! Unifique - Muse -- Constitutional -- ownership -- of US school!
/loch dn tn grd2''x~tmp fs rcvr + gml cmd fon td/ /2''vf(xF'~tmp dn tn)< fs u 8''frch 2''UI' td chn < vd LN'' kntrolz/ /4'p''~dn tn < tstx i.e. ~tmp cmd < gml abv kol stachon/ /~vaar fr grd2''x < contnt i.e. gml cmd fon < txt bx || td unit/ /Tvf(xgrd2''~tmp fs 2'' inch kf'' grdz < z''X'k' pn gml cmd LN'' fon td)/ /O 2'' smultz inch kf'' grdx rul~tmp thrm 2''vkRx rvcr i.e. paavlow + stapach vaakuum/
Great video. Thanks
What specific Oscilliscope do you use? And do you recommend a specific non-DIY tone generator?
It’s just an inexpensive Hantek and works very well. The signal gen is also a cheap unit from AliExpress. Honestly anything decent will be ok, we’re just doing audio frequency work after all.
Guitar smp builders look elsewhere. The main subject is not used
One of the best explanations of load lines and the effect on amplification I've seen in years! Thank you for posting this.
"Let's begin nowwww..."
Drawing never work Illusion... physical activity materials piesa purtyxhQn then your jvy tools
Awesome 👍👌
This is genius! You guys deserve a patent for this !
lol this comment was meant to go to the block g distortion bug bias video
You make these "cheap" russian tubes work for hifi, fantastic! For negative bias Voltage I often use a small 1" by 1" print trafo 230V/9V and hook it up the the 6,3V ac heater winding (or to mains and use a voltage doubling bridge depending on -V needs). My local supplier has these small trafos for 0,95€ and they're light and small enough to be placed under the chassis.
Nice circuit! I especially like the power supply. Most people either use no MOSFETs at all or go crazy with super complicated transistor circuits. I just checked and the FQP10N60C is very affordable and available.These should also work as mosfet followers in the signal chain. Some ideas: No input transformer and use a 6N2P with higher gain for preamp tubes, Ra 120k with Va about 200V should give nice swing. And add the CCS tail could to your -22V supply. 6H8C only has a datasheet-µ of 21,5 , real life v/v of maybe 15.. Do you think this will work well with a 6N2P/12ATX or does the GU17 need the beefier driver with more current capability?
Hard to say until you give it a try. Those little input transformers are inexpensive and available on AliExpress though. In regards to the 10N60c I’ve actually just designed a A2 cascode output stage amp that uses one to drive the cathode of the output tube! When I get it finished up I’ll make a video about it. It’s 10wpc with a single el34 per channel SE.
@@Edgarbopp I might just do that - I have all tubes and parts on hand..Regarding the sand-assisted cathode drive, yes I have read about it on diyaudio. Looking forward to that video as I have experimented with a screen-grid driven 6P45S SE amp (I have nice unused op-iron for it) during covid but struggled to get the driver right and it sits unfinished
Love your educational videos especially this one and the load lines one! Very easy to follow and understand. Regarding transformers, output ones, I am looking at trying a 5k:5ohm LL1682 but my speakers are 8ohm, was wondering what problems would that cause like maybe bandwith issues. Need a good 10k:8ohm in my circuit but 8k would work. My output tubes are 6p1p in push pull A class. Thank you for posting all this great stuff and looking forward to new affordable tube discoveries and projects. PS: Russian 6H7C are very cheap preamp tubes with good linearity and paraleled are capable to drive interstage trafos, could be an affordable alternative to 6SN7 with a little less gain. They where intended for class B output stages. George.
I’ve had very good luck with the 6H8C too.
What pa are you using
Union PA. Random parts with WWR. Jet pack torso.
31
if I wanted to calculate the output power that the amplifier provides before switching to class B, how can I do it? that is, I want to know the power only in class A. thanks
Great tutorial, thank you
Happy to help
Did you bypass the obc? Or just hook them up to original positive and negitive cables?
nice video thanks, a doubt arises at minute 36, if the supply voltage is 360v how does the signal oscillate up to 520?
Good question! Because the output transformer is an inductor it has a reactance not a resistance. It supplies the voltage above supply. Inductors supply voltage to preserve current. They’re a type of current source.
@@Edgarbopp That's incredibile, so when the tube oscillates in class A, before the cut-off at the bottom, it always reaches that extra voltage? Thanks for these clarifications
I have 2 transformers that do not have markings or data sheet. Only a schematic of where it belongs. Do you mind if I email you some questions to help identify the pins of primary/secondary? Thank you.
Just wanted to say I enjoyed this video. I already have a OTL amp based on this tube (16 of them!). Hope you give some detail about the output tranformer. Not sure what EM label near mosfet signifies. Does it mean encasement mode?
Enhancement mode. The output transformers I purchased on AliExpress. I can find the listing for them if you want. Glad you enjoyed the video.
I had to subscribe. I like your calm demeanor and straight forward informative approach! Thank you
Very nice of you to say.
You are awesome bro!!! Thanks!!! How are they holding up??
Dude, do everyone (including yourself) a favor and write a script. Its really hard to watch and understand your videos with all the "uuhh" and "uuummm" in that monotone. The content is cool, the execution is rough.
Please feel free to not consume my content.
I had one in late 60’s. Loved it
Why did you use an RCA instead of a XLR?
My sound card has a unbalanced input
I have Epoch. I was considering big battery also. Very similar kit. I bought the 60ah kit and like you mentioned it wasn’t enough. I had to upgrade a d buy one more battery to bring me to 90ah. The epoch is a nice kit
I have repaired mine a couple times in 20 years . No longer able . any replacement speakers that would be ok ? Do they need to be 4 ohm ?
What about negative feedback to make it regulated?
where the hell is June?
Wow 😂 I just tell the high output impedance source alter my headphone very much and no reverb 😂 I can't see the reverb more effect when damping factoe is low, just frequency response. With my own, the bass is more deep and the sound signature is warmer or duller 😂.
Can you make a same tutorial for biasing otl amps? cuz I just built one recently and I wanna tune it to sound good because it sounds very bad right now😂 my tubes are 6h8c and 6l6gc my setup is self biasing but I think I think I messed up with my resistor values on the cathode
I found this helpful how you test transformers
OMG!!! I listened to and read this for years!! Thanks sooo much for the upload
Hi Doug. I have the same kit. Does your battery display on the batteries stay on all the time. Mine does and it does worry me.
It does, though it doesn’t worry me. The draw from the led is probably an order of magnitude less than the leakage current of the battery cells themselves.
@@Edgarbopp Thanks doug. How about the breaker. Do you shut them off and just leave it on. Seems like a good battery. Much better then lead acid.
@@steves7458I’d hate to wear out that breaker by using it as a on off switch. I leave them on.
You can power the meter by getting the 48v from the key switch on terminal@@Edgarbopp