Hi there!
I'm looking to build a very basic tube amp that can be hooked up to an iPod, CD layer or something of that sort.
I've asked here before and somebody suggested a modified version of a Fender Champ, but that's where the thread died. Now, after surfing for hours and hours every night I still can't find a nice layout to follow.
If anybody has a layout that I can use please post it. I'm after a basic, no frills tube amp.
Thanks!
I'm looking to build a very basic tube amp that can be hooked up to an iPod, CD layer or something of that sort.
I've asked here before and somebody suggested a modified version of a Fender Champ, but that's where the thread died. Now, after surfing for hours and hours every night I still can't find a nice layout to follow.
If anybody has a layout that I can use please post it. I'm after a basic, no frills tube amp.
Thanks!
What exactly are your goals? You need to tell us quite a lot more before you will get useful responses..
Do you intend to drive speakers, and if so what?
Do you want stereo or is mono ok?
What sort of skill level do you bring to the table?
A fender champ is a guitar amplifier, hardly the best choice for listening to music. Was that suggestion based on your wanting something similar to an iPod dock for example?
Where will it be used?
What is your budget?
So on and so forth..
Do you intend to drive speakers, and if so what?
Do you want stereo or is mono ok?
What sort of skill level do you bring to the table?
A fender champ is a guitar amplifier, hardly the best choice for listening to music. Was that suggestion based on your wanting something similar to an iPod dock for example?
Where will it be used?
What is your budget?
So on and so forth..
Based on the the vague information you gave, my advice would be to get a PCB based design (such as the Tubelab SimpleSE) as it leaves less room for problems (and in the case of the SimpleSE is a tried and true design.)
Beyond that, we need to know what it is you want exactly. If you answer Kevin's question, plus how loud do you need it to go, what sort of size do you want it to be and how much do you want to spend, should give a better basis for a recommendation.
Beyond that, we need to know what it is you want exactly. If you answer Kevin's question, plus how loud do you need it to go, what sort of size do you want it to be and how much do you want to spend, should give a better basis for a recommendation.
Thanks for the responses.
I'm not new to this tube amp stuff, however, my entire experience is limited to guitar amps. I've built a few of those, always had a layout to check, verify with.
What I would like to build is a simple amp, stereo if possible, but nothing fancy. I would like it to have a power amp big enough to drive a couple speakers, nothing fancy there either, and I'm open to any suggestion regarding the speakers as well.
I was thinking about the champ modifications somebody suggested here. I guess that would take a preamp and power amp for each channel (left and right) along with a single power supply. I don't know much about anything regarding hifi amps, so I don't know if a tube rectifier would be better than a SS one for that particular application.
I intend the amp to work with MP3 players, or even a portable CD layer. That's the use, nothing else.
I guess something like 5W is enough, a 5W guitar amp can get pretty loud so that's what I'm using for comparison.
I'm not new to this tube amp stuff, however, my entire experience is limited to guitar amps. I've built a few of those, always had a layout to check, verify with.
What I would like to build is a simple amp, stereo if possible, but nothing fancy. I would like it to have a power amp big enough to drive a couple speakers, nothing fancy there either, and I'm open to any suggestion regarding the speakers as well.
I was thinking about the champ modifications somebody suggested here. I guess that would take a preamp and power amp for each channel (left and right) along with a single power supply. I don't know much about anything regarding hifi amps, so I don't know if a tube rectifier would be better than a SS one for that particular application.
I intend the amp to work with MP3 players, or even a portable CD layer. That's the use, nothing else.
I guess something like 5W is enough, a 5W guitar amp can get pretty loud so that's what I'm using for comparison.
Regardless of rectifier technology, SS or vacuum, implementation details are the name of the game.
"El Cheapo" should be right up your alley. Look the schematic over, then read the LENGTHY saga here. EC works with a "standard" CDP, whose max. O/P level is 2 VRMS.
Attachments
Being a guitar amp, I wouldn't do the Champ mods, if you're going to build an amp for hifi use, might as well go from a hifi design.
If you're fine with P2P wiring, something like the El Cheapo that Eli mentioned would be good. For five to ten watts, a Single Ended 6L6/EL34/KT88/etc amp would give you that, for a bit more (twenty or thereabouts) a push pull EL84 amp could be on the cards.
Here's a few threads to get you started, have a look and see what you think:
stereo SE kt88 build ... abdellah diyaudioprojects design
EL84 Amp - Baby Huey
The Red Light District - another PP EL84 amp
Still can't find a layout I can follow. I got a nice schematic, but I'd love to have a layout so I can check what I'm doing. This is my first hifi amp and I don't wanna screw up.
And yes, actually, I would prefer point to point wiring. 😀
And yes, actually, I would prefer point to point wiring. 😀
I think what he's looking for is a wiring diagram. Not many seem to exist. THis is why I felt I had to to the ST-70 as my first build. Lots of pics!
By layout, do you mean where to physically place the components ie transformers, tubes, etc in the chassis?
Help me understand this schematic. The lower driver does not seem to get a signal, except through the feedback from the output transformer.
Also, the double bubble from the cathodes of the drivers does not seen to have a corresponding link on the schematic.
Boozhound Laboratories
About halfway down the page, he talks about laying out an amp...is that the kind of thing you were looking for?
Good site to bookmark if you're a tubehead anyway, if you haven't 😀
Another vote for the Tubelab Simple SE. I have built a similar design and am using the $20 Edcor XSE15-8-5k output transformers and Antek Inc 1T250 power transformer. In terms of sound quality per dollar spent, I doubt it can be beat.
~Tom
~Tom
Loren,
The small signal circuitry in "El Cheapo" is a differential gain block. It is both splitter and driver. The 2 halves are coupled at the cathodes. The circuitry goes by other names: long tailed pair (LTP), Schmitt, and cathode coupled.
The interlocked circles are the symbol for a constant current element, which in this case is a sink. The constant current sink (CCS) in the tail of the splitter/driver forces symmetry between the 2 sides. If current on 1 side goes up, current on the other side must go down. The CCS is the glue that allows the non-inverting triode's grid to be the point at which loop NFB is sucessfully applied.
Look at the right side of the PSU portion of the drawing. Please notice the circuit fragment labeled Constant Current Source. The cascoded FETs and ancillary passive parts, along with a connection to B-, comprise the interlocked circles on the drawing's signal part.
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Great explanation. Thanks. I wonder about the signal phase delay as the feedback is reintroduced. I would expect that there would be some phase delay or is that not the case?
Works like gang busters. "El Cheapo" is designed to be built with only a multi-meter as test equipment. Phase compensation is brute force. The LTP load resistors are inductive wirewound, which peaks HF response. Connecting a 150 or 120 pF. cap. from speaker "hot" to ground shorts the NFB loop out 2+ octaves away from the audio band. The better the O/P "iron", the higher that F3 can be. The brute force method relies on the natural HF roll off of the "iron".
The PSU takes no prisoners and the signal topology is quite valid. O/P trafo quality is the limiting factor on performance. Cheapy guitar amp trafos yield an OK amp. Dynaclone Z565 trafos yield a very good amp. I would not be afraid to use exotic Tamura stuff in that design. 😉
Budget? I could go up to $400, but I want this as a gift for my kid, and we all know how kids subject electronics to extremes. 😀
I got a few tube guitar amps, all build from scratch and they're amazing. I started on this because I had the layouts, it's what gives me the extra security you know? Something like ok, I can always check and be 100% sure.
To illustrate this let me give you an example. I always wanted a little guitar amp with a ton of gain. Found it, just what I wanted, but only the schematic. I took the time to go through it and make my own layout. That was a few months ago. I have not built it yet because I don't have that extra security I was talking about... 🙁 Oh, and I've gone through the schematic a few time tracing the signal and I'm pretty sure I got it right, but still....
Here's a more detailed info on what I would like to make...
It's a little amp, by little I mean 5W or so. I don't care much about a tone stack, master volume is enough. Stereo, if possible, but not a must. It'll only be used with a CD player or an iPod.
If the entire amp is not an option, then a preamp will be fine if it can be used with powered speakers. Not the best, but I guess it's gonna be better than nothing.
The idea of what I was looking for can be seen here:
http://www.turretboards.com/layouts_schematics/fender/layouts/champ_aa764_layout.gif
That's what I've been searching for, obviously not a champ but a simple hifi amp.
I really appreciate all the help, specially since I'm new here. Thank you so much!
I got a few tube guitar amps, all build from scratch and they're amazing. I started on this because I had the layouts, it's what gives me the extra security you know? Something like ok, I can always check and be 100% sure.
To illustrate this let me give you an example. I always wanted a little guitar amp with a ton of gain. Found it, just what I wanted, but only the schematic. I took the time to go through it and make my own layout. That was a few months ago. I have not built it yet because I don't have that extra security I was talking about... 🙁 Oh, and I've gone through the schematic a few time tracing the signal and I'm pretty sure I got it right, but still....
Here's a more detailed info on what I would like to make...
It's a little amp, by little I mean 5W or so. I don't care much about a tone stack, master volume is enough. Stereo, if possible, but not a must. It'll only be used with a CD player or an iPod.
If the entire amp is not an option, then a preamp will be fine if it can be used with powered speakers. Not the best, but I guess it's gonna be better than nothing.
The idea of what I was looking for can be seen here:
http://www.turretboards.com/layouts_schematics/fender/layouts/champ_aa764_layout.gif
That's what I've been searching for, obviously not a champ but a simple hifi amp.
I really appreciate all the help, specially since I'm new here. Thank you so much!
I think I will resurrect this thread, rather than starting my own. I'm basically looking for the same thing. I need it to be stereo, and have the option of driving 4,8, and 16 ohm loads. 5-15 watts per channel. Budget is $200-300.
I would also like to build a 5.1 amp as well. Same specs on that, but with a budget of $1000 or so.
I have experience building amps, I can do the layouts myself. I just need the schematics. I also would like speaker recommendations. I would like to spend maybe $200 per speaker.
Looking for the best price/sound quality.
Thanks!
I would also like to build a 5.1 amp as well. Same specs on that, but with a budget of $1000 or so.
I have experience building amps, I can do the layouts myself. I just need the schematics. I also would like speaker recommendations. I would like to spend maybe $200 per speaker.
Looking for the best price/sound quality.
Thanks!
May I recommend the Fostex fe-206e in the Fostex recommended enclosure for the fe-208 (google should be able to locate that). Or some of the smaller designs for the surround speakers. Lots of sawing and gluing, but wonderful price/quality ratio and 5W gets you a lot of sound pressure so amps can remain modest.
Head over to the full-range forum on this site and you'll find a wealth of other similar speaker designs which fit the same bill.
Kenneth
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