Hearinspace… thanks for the feedback. Yea, I probably need to restate my position. I “assembled“ plenty of amps. That said, it was almost like painting by numbers.
I am starting to see a signal path, via a schematic; however, I have no idea what is going on and if a value is changed, what might be the result. I’m extremely fascinated by this and would like to learn more. So, I continue to read and ask questions…
I am starting to see a signal path, via a schematic; however, I have no idea what is going on and if a value is changed, what might be the result. I’m extremely fascinated by this and would like to learn more. So, I continue to read and ask questions…
If you don't mind a suggestion and like to build, why not make a very simple single ended circuit with as basic a power supply and loading scheme as could possibly work and then one area of interest at a time, learn what variations can be applied?
A one or two tube mono amp with a single full range driver to work into is all you need, and aside from transformers, additions or variations can
cost little more than a coffee and a donut.
Just an idea.
A one or two tube mono amp with a single full range driver to work into is all you need, and aside from transformers, additions or variations can
cost little more than a coffee and a donut.
Just an idea.
You know, that’s not a bad idea…. I know where to get resistors and capacitors; however, buying power and output transformers has me a little lost. I guess I would need to find a simple circuit, then spec out the transformers? Or, are there some certain values, of transformers that will work?
Hearinspace,
Good Suggestion!
For the most part, I did not use full range drivers.
The only ones I used for a while, was an early version of the Fostex FE208.
I dampened the whizzer cone with different materials, I did not like the sound; then I carefully cut the whizzer to just a 1/4 inch. Sounded great!
I almost exclusively use many different manufacturers 2 way speaker systems. Helps to validate the performance of the amplifier.
I have been doing the following with many of my amplifier designs.
Two tube single ended
Mono Block
DHT output tube
Pentode output tube
Beam Power output tube
No negative feedback
Ultra Linear (which is intrinsic local negative feedback)
Triode wired Pentode and Beam Power (which is intrinsic local negative feedback [NF])
Schade NF; Output plate to driver cathode NF.
Tube rolling: EL34 versus KT77 (don't forget to wire pin1 to pin 8);
More tube rolling: 5881, 6L6GC, and KT66. Now you know one of the reasons why I like self bias (plug and play)
And I did push pull amplifiers and balanced amplifiers
Three tube
Mono Block
DHT output tube
Pentode output tube
Beam Power output tube
No negative feedback
Ultra Linear (which is intrinsic local negative feedback)
Triode wired Pentode and Beam Power (which is intrinsic local negative feedback)
Tube rolling: EL34 versus KT77 (don't forget to wire pin 1 to pin 8)
More tube rolling: 5881, 6L6GC, and KT66. Now you know one of the reasons why I like self bias (plug and play),
And why I use very well matched tubes for push pull, with individual self bias, or with common self bias.
Have Fun!
Good Suggestion!
For the most part, I did not use full range drivers.
The only ones I used for a while, was an early version of the Fostex FE208.
I dampened the whizzer cone with different materials, I did not like the sound; then I carefully cut the whizzer to just a 1/4 inch. Sounded great!
I almost exclusively use many different manufacturers 2 way speaker systems. Helps to validate the performance of the amplifier.
I have been doing the following with many of my amplifier designs.
Two tube single ended
Mono Block
DHT output tube
Pentode output tube
Beam Power output tube
No negative feedback
Ultra Linear (which is intrinsic local negative feedback)
Triode wired Pentode and Beam Power (which is intrinsic local negative feedback [NF])
Schade NF; Output plate to driver cathode NF.
Tube rolling: EL34 versus KT77 (don't forget to wire pin1 to pin 8);
More tube rolling: 5881, 6L6GC, and KT66. Now you know one of the reasons why I like self bias (plug and play)
And I did push pull amplifiers and balanced amplifiers
Three tube
Mono Block
DHT output tube
Pentode output tube
Beam Power output tube
No negative feedback
Ultra Linear (which is intrinsic local negative feedback)
Triode wired Pentode and Beam Power (which is intrinsic local negative feedback)
Tube rolling: EL34 versus KT77 (don't forget to wire pin 1 to pin 8)
More tube rolling: 5881, 6L6GC, and KT66. Now you know one of the reasons why I like self bias (plug and play),
And why I use very well matched tubes for push pull, with individual self bias, or with common self bias.
Have Fun!
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There are kits available, some of them providing all the components and others offering just a PCB and a parts list. There are also many DIY projects that don't offer the components but specify what you need to build them.
TubeLab. for one, is a well-regarded provider of affordable PCBs with instructions for assembly.
http://tubelab.com/pc-boards/
It's too early to worry about that yet. Do you still have any tubes lying around?
A few, yes…. I have 2 Brimar 12AU7 (maybe it’s a 12AY7)., a 5AR4, 5U4(G) I think, and some EL84’s…. I also have a SE amp that these go in; however, the sound is a little too light (not the warm and syrupy sound, I want).
that said, the amp has plenty of air and holographic sound that many may love. For me, I want more of an older sound.
I’m comfortable with point to point wiring; however, a board is fine as well…
What is the amplifier? Or do you know the specs of the OPTs?
Sounds like sharing the schematic and specs of that amplifier might be a good introduction into getting the sound you are looking for.
Unfortunately one thing you learn when building your own tube amplifiers is that there is no substitute for reasonable quality transformers, and they cost. Sometimes looking out for a second hand amplifier just for the components is as good a place to start as anywhere.
The other hassle is building an amplifier that is fit to be used on a daily basis, so it is safe and properly enclosed. There is a lot to be said for looking at the projects that @stephe has done, she has a presence on youtube, where she takes a cheap Chinese kit, and extracts the best sound from it.
A picture is worth 200 Words.
A complete and accurate schematic is worth 1000 Words.
The name, and specification, and general design details of a loudspeaker is worth 500 Words.
Ported, closed box, 2-way, complex crossover or simple crossover, etc.
The sound you get is the result of the Total system.
It is important to consider how well the amplifier and speaker interface, and affect each other.
A complete and accurate schematic is worth 1000 Words.
The name, and specification, and general design details of a loudspeaker is worth 500 Words.
Ported, closed box, 2-way, complex crossover or simple crossover, etc.
The sound you get is the result of the Total system.
It is important to consider how well the amplifier and speaker interface, and affect each other.
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I'm posting here because of your first question.
I'm not a math guy nor do I know enough about computer stuff to tolerate working with simulators that require staying up to date with updates in software and GUI, so I have learned to do everything as a build and measure project. The amp I listen to now was based entirely on the limitations presented by the output transformer that I was given and took me three years of trying everything I was interested in checking out before deciding it was just right as it is.
If interested in step by step move through circuit - I might start with simple single EL84 , triode connected spud, powered with a one cap filtered supply , all done on a 24" x 24" piece of ply ,(that big to accommodate the additions to come and leave room for safe poking) . Whether you can work on it 24/7 or half an hour on Saturday afternoons will of course determine how quickly the board becomes populated.
That's the sort of thing I am advocating, and if that's what you have in mind then I'm happy to put some effort into suggestions/help with details.
If your interest is to get quickly to the finished amp with sound you want then I'm sure others can make brand or schematic suggestions.
Thanks
My answer comes out of my own experience of being in a rush for great results and later having to back up and start over with basic circuit principles and variations. In the course of doing that I found learning the electronics to be both worth the time spent and interesting in its own right.
I'm not a math guy nor do I know enough about computer stuff to tolerate working with simulators that require staying up to date with updates in software and GUI, so I have learned to do everything as a build and measure project. The amp I listen to now was based entirely on the limitations presented by the output transformer that I was given and took me three years of trying everything I was interested in checking out before deciding it was just right as it is.
If interested in step by step move through circuit - I might start with simple single EL84 , triode connected spud, powered with a one cap filtered supply , all done on a 24" x 24" piece of ply ,(that big to accommodate the additions to come and leave room for safe poking) . Whether you can work on it 24/7 or half an hour on Saturday afternoons will of course determine how quickly the board becomes populated.
That's the sort of thing I am advocating, and if that's what you have in mind then I'm happy to put some effort into suggestions/help with details.
If your interest is to get quickly to the finished amp with sound you want then I'm sure others can make brand or schematic suggestions.
Thanks
I understand the schematic will be greatly helpful. I'm looking for it; however, I haven't found the dang thing...
Regarding the rest of your post... I'm well aware of the synergy matching, etc, etc, etc... Not trying to be a punk; however, I've been doing this for a long time, as I'm sure you have. I'm fully adept at creating good sound from combinations of product, as I'm sure you are. The amp, in question, has been put into a number of systems, changing out interconnects, speaker wire, power conditioners, tweaks, and so much more...
As I've said, this amp may be for a lot of people; however, I'm wanting something a little different. The builder and I have talked about this numerous times. I'm not wanting to really change much, on this amp, if at all, as I will most likely be selling it. I'm trying to provide people with as much of a view into what my most recent amp is and see what changes could be made, to help with what I'm trying to get.
You seem to have the skills to build your own. I do use simulation a lot to build amps. Its as accurate as the models you give it, but there are pit falls. It also won't tell you how its sounds but will show you the distortion sources. However for tweaking components and trying ideas out I find it essential.
Depending on the amount of NFB you want that amp may not have quite enough gain for EL34. LTP second stage may be better still using the 12BH7, but my designs tend to always end up analytical as you would say. Some of the colouration could come from the HT dropping on the peaks - like a compressor.
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2nd harmonic distortion also causes 2nd Order Intermodulation distortion.
3rd harmonic distortion also causes 3rd Order Intermodulation distortion.
Most discussions of distortions seem to center around harmonic distortions, and not as oftern center around Intermodulation distortion.
Perhaps "Syrupy" is mostly from distortion.
Perhaps "Syrupy" is mostly from moderate high frequency roll off.
Perhaps "Syrupy" is from a little of both.
Perhaps "Syrupy" is from something completely different
Most discussions of amplifier's damping factor centers around the interaction with the woofer.
But how about the interactions with the crossover, and the mid, and the high frequency drivers; they have resonances, and they have un-flat impedance curves, are often more reactance than resistive, etc.
Just to list a few, but not all factors that create how a playback system sounds.
Often, a given amplifier can easily be adjusted to have: 1. certain kinds of distortion, 2. certain frequency response, and 3. different damping factor.
Most of those are easy modifications to try, especially if the amplifier does Not have global negative feedback.
Trying to adjust 1, 2, or 3 by changing parts, parts values, etc., with those parts being Inside the Negative Feedback loop, is like trying to get a rubber crutch to work well.
It might just be time to play with an old circuit design, spin the roulette wheel, and see if you are lucky or not.
3rd harmonic distortion also causes 3rd Order Intermodulation distortion.
Most discussions of distortions seem to center around harmonic distortions, and not as oftern center around Intermodulation distortion.
Perhaps "Syrupy" is mostly from distortion.
Perhaps "Syrupy" is mostly from moderate high frequency roll off.
Perhaps "Syrupy" is from a little of both.
Perhaps "Syrupy" is from something completely different
Most discussions of amplifier's damping factor centers around the interaction with the woofer.
But how about the interactions with the crossover, and the mid, and the high frequency drivers; they have resonances, and they have un-flat impedance curves, are often more reactance than resistive, etc.
Just to list a few, but not all factors that create how a playback system sounds.
Often, a given amplifier can easily be adjusted to have: 1. certain kinds of distortion, 2. certain frequency response, and 3. different damping factor.
Most of those are easy modifications to try, especially if the amplifier does Not have global negative feedback.
Trying to adjust 1, 2, or 3 by changing parts, parts values, etc., with those parts being Inside the Negative Feedback loop, is like trying to get a rubber crutch to work well.
It might just be time to play with an old circuit design, spin the roulette wheel, and see if you are lucky or not.
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