bloozestringer,
Way too long of a thread here. So I do not know what exact amplifier circuit you are putting the KT77 into.
The important thing is to use the tube within its specifications.
Such as g1 DC return resistance versus self bias or versus fixed bias.
And plate and screen voltages, currents, and dissipation; and cathode current.
Given proper design within those specifications . . .
I use the JJ KT77 tubes from eurotubes.com.
They re-test all those after they get them from JJ in Slovakia.
Just my opinions.
Way too long of a thread here. So I do not know what exact amplifier circuit you are putting the KT77 into.
The important thing is to use the tube within its specifications.
Such as g1 DC return resistance versus self bias or versus fixed bias.
And plate and screen voltages, currents, and dissipation; and cathode current.
Given proper design within those specifications . . .
I use the JJ KT77 tubes from eurotubes.com.
They re-test all those after they get them from JJ in Slovakia.
Just my opinions.
So does anyone know what the limits are on this design. Can it be scaled up to run something like 60-80W/Ch. I'm looking for a design like that. Is there anything on the forum like that with boards hopefully??
Thanks. I’ve used JJ’s from Eurotubes in my guitar amps for years with zero issues.
I plan on using KT77’s in this Baby Huey instead of EL34’s.
@bloozestringer
+1 on KT77 from eurotubes being you on the US.
@Freecrowder
most users report best results around 40-50 Wpc even with big tubes (gain is small, so there's small margin to reach good DF and THD figures). Depending on your speakers it could be acceptable: I run EL34 at 450V and 6k6Raa with good sonic results, by lowering the Raa to around 5k you could reach the 60+ Wpc you need, but be aware that this is not a plug and play kit: every tube at every voltage and every load needs its own optimisation. Here you'll find some people ready to share its own preferences based on their own system, their most played music and personal preferences.
+1 on KT77 from eurotubes being you on the US.
@Freecrowder
most users report best results around 40-50 Wpc even with big tubes (gain is small, so there's small margin to reach good DF and THD figures). Depending on your speakers it could be acceptable: I run EL34 at 450V and 6k6Raa with good sonic results, by lowering the Raa to around 5k you could reach the 60+ Wpc you need, but be aware that this is not a plug and play kit: every tube at every voltage and every load needs its own optimisation. Here you'll find some people ready to share its own preferences based on their own system, their most played music and personal preferences.
I've used the amplifier for some time now with 6n2p tubes, and all of them has been noisy. Hiss which is coming and going. I got some 6n2p-ev a few weeks back and have been running the these for some time, and they seem much better.
Good news tbaashus! Hope they stay hiss-free. What brand did you get? Not sure it was manufactured by many factories in Russia, I have seen only Voskhod.
I have several 6n2p-ev (Voskhod) but have yet to use them.
I have several 6n2p-ev (Voskhod) but have yet to use them.
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I haven't started on my build of the BH yet. But I started to plan the build and was thinking of what preamp to build as well, when I read this previous post.
I have and Aune S16 dac and an RJM Emerald phono that I will connect. Don't I need a preamp for the BH? Or do you have any other suggestions for a suitable build?
Sorry for any stupid questions... but how come I don't need a preamp?
I don't mind building a pre as I already had my mind set on it but if there's really no need... one less case.
The outputs of your sources should be loud enough without preamplification (your emerald is in fact phono preamp), so the advice of Francois is good. You could use a passive pre or buffer without gain in front to provide volume control and source switching, but you could also build that into your BH as many have done. There are many options, and equally many offerings you can peruse here on diyaudio so I think the question is more what you prefer.
As silasmellor wrote you, no need for a preamp except you want to go deeply in AB2 with 6L6GC-like tubes, that is not the typical application of the BH.
In two of my amps I've implemented a devide that can automatically switch between the two RCA inputs or a bluetooth device. Simple and effective: you can connect your phono and a bluetooth device with FLAC files and remotely switch them as you like.
In two of my amps I've implemented a devide that can automatically switch between the two RCA inputs or a bluetooth device. Simple and effective: you can connect your phono and a bluetooth device with FLAC files and remotely switch them as you like.
Thanx, that sounds great. Will definitely look into such an implementation... need a switch and a volume control. Perfect! 🙂
I think the tubes I've got are made by Novosibirsk. The logo on the tubes are similar to the logo found on this page: Russian Factories of Vacuum Tubes
Perhaps we could persuade Zintolo to start a thread to show us how he did his implementation of the switch/volume control. 😱🙂😀 What do you say, Roberto?
Ciao Francois,
the look is still very bad, no case yet and still everything mounted on the fly à la "please mother-in-law, touch there" (new house is eating my time).
It's a PCM5102A based Bluetooth 32bit/384kHz DAC ( https://www.ti.com/lit/ds/symlink/pcm5101a.pdf?ts=1633976198539 ) that usually connects the outputs to the analog inputs, but when a blutooth is connected to the device, automatically switches the output to the internal DAC.
Volume control is a classic stereo potentiometer.
the look is still very bad, no case yet and still everything mounted on the fly à la "please mother-in-law, touch there" (new house is eating my time).
It's a PCM5102A based Bluetooth 32bit/384kHz DAC ( https://www.ti.com/lit/ds/symlink/pcm5101a.pdf?ts=1633976198539 ) that usually connects the outputs to the analog inputs, but when a blutooth is connected to the device, automatically switches the output to the internal DAC.
Volume control is a classic stereo potentiometer.
Ciao my friend! Hope your work and house renovations are progressing well!
When I hinted at a new thread I meant the schematic and connections, not necessarily the physical implementation, to help us electronics-challenged builders build our own switch/bluetooth etc. Only when you get more time available.
When I hinted at a new thread I meant the schematic and connections, not necessarily the physical implementation, to help us electronics-challenged builders build our own switch/bluetooth etc. Only when you get more time available.
From my experience, especially if you're into DIY and building amps, it make sense to have a "preamp"-type that is the heart of the system.
The diya store has the Mesmerize buffer PCB that allows for multiple input switching and volume control. tomchr (Neurochrome) has a few PCB's that can be used together to make such a unit.
When I decided to go all-out, I built the AMB alpha10 pre-amp. It supports multiple inputs and outputs, volume control via discrete resistors, all remote-controlled. So you could connect that to 2 or 3 different amps (assuming you have multiple speakers too) and control it all from a single remote.
Having such a unit simplifies the amplifier itself, as you don't need to incorporate volume control or multiple inputs to every build. And as we know, there will always be another project so it helps when there is less work to do.
Many DAC's these days have remote and volume control, so if you only use digital you can use that as a source/preamp AIO. Others also include an analog input (such as the Benchmark DAC3L) to connect your phono input. They may seem expensive but from experience, once you factor in case and other costs you won't save much if at all going DIY.
The diya store has the Mesmerize buffer PCB that allows for multiple input switching and volume control. tomchr (Neurochrome) has a few PCB's that can be used together to make such a unit.
When I decided to go all-out, I built the AMB alpha10 pre-amp. It supports multiple inputs and outputs, volume control via discrete resistors, all remote-controlled. So you could connect that to 2 or 3 different amps (assuming you have multiple speakers too) and control it all from a single remote.
Having such a unit simplifies the amplifier itself, as you don't need to incorporate volume control or multiple inputs to every build. And as we know, there will always be another project so it helps when there is less work to do.
Many DAC's these days have remote and volume control, so if you only use digital you can use that as a source/preamp AIO. Others also include an analog input (such as the Benchmark DAC3L) to connect your phono input. They may seem expensive but from experience, once you factor in case and other costs you won't save much if at all going DIY.
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Ciao Francois, work is going fine thanks, whilst the house it's going slower than I would like, but it's going! I hope you are going fine too.
The bluetooth module has one analog input and one analog output.
When no bluetooth device is paired to the module, a dual relay connects directly the analog inputs with the outputs.
When a bluetooth device is paired to the module, the relay automatically connects the DAC to the analog outputs.
It is the module itself that automatically switches the onboard relay when a bluetooth device is connected.
After the module I have a standard stereo volume, then to the amp.
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I think everything really depends on the specific needs, case by case: for me that multi-amp multi-speaker managing preamp would be way redundant, and a simple bluetooth module will be enough for tv+bluetooth in the living room and same for the phono+bluetooth in the attic.
I only have my turntable (phono pre) and a headless Daphile linux server through my dac connected. And I really don’t think that will change much over the years. Have had this setup for 10 years already.
And if I can keep the cases to a minimum the wife will be happier and it’s also easier to keep a clean look.
And if I can keep the cases to a minimum the wife will be happier and it’s also easier to keep a clean look.