Do handwired solid state amps exist?

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Lynxtrap

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I think this was along the lines of what I was thinking. Relatively easy to swap out parts by the look of it.

It sure is, easier than most solid state amps for those of us who don't like to work on PCBs.
I think the T60 (released in 1961 or '62) was one of the earliest SS amps for musical instruments, maybe even the very first for bass.
I guess it was easiest for Vox to just build it like their tube amps.
Still more compact and much lighter in weight than a 60W tube amp.

McCartney and Entwistle used them for a short while, but they burned power transistors on a daily basis I guess. Mine is modded with heatsinks.
 

Swingcat

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I was thinking about old amps and how much easier they are to replace parts etc and how people like to keep them going for years and years and got to thinking about the future when valves/tubes might not be so easy to obtain etc pt and ot trabsformers aint cheap either.

A lot of modern solid state amps use quite specialised components that cant be repaired so i wondered if there was any mileage in building a hand wired solid state amp? Or maybe a hybrid?

Perhaps good amps are just too cheap to bother worrying about it? Or maybe they will last much longer than a valve amp anyway. I do have a peavey tnt150 bass amp from the 80s that is still going strong.

Any thoughts? Is this a dumb idea?
Yes, it's easier to replace parts on older amps, but what's even easier is to not HAVE to replace any parts!
Most of the high end (Quilter, Fender Tone Master series amps, and many others) use Class D amplification, like the stuff in your cell phone and similar devices.
Class D is AMAZINGLY reliable, and works for many years without having to touch anything!
And some (as I mentioned above) are indistinguishable from the time counterparts, and are sometimes less than half the weight of an equivalent tube amp.
 

printer2

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I would love to make a hand-wired point-to-point SS amp. I'd use transistors in those big TO-126 and TO-220 packages (overkill for small signals, I know...), and power it with ±35 volts like the big SS hi-fi amps. Maybe even use P- and N-channel MOSFET pairs wired up as Inverters for the gain stages. I'd also use big MOSFETs in TO-3 packages for the power section, output through an audio transformer. A pipe dream perhaps, but it's MY pipe dream, darn it...


Oh, his website seems to be up again.

 

Arfage

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Sure. The preamps and some phase inverters in Music Man Amps. I know there are a lot more than that as well.
 

sds1

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May I ask what that brown squarish component is in the first picture? Never seen that in SS or any other amps.
Hope to learn something new today....
It's a power transformer, I'm sure you've seen them before in other amps but maybe not this construction style which I think is called "open-frame".
 

richa

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In general just to be clear I don't think that the handwiring part gives it any special abilities, I think I meant point to point wiring really. although It would still need to be handwired as I don't have the equipment to do anything else.

I don't have anything against PCBs as such but I feel that there is more chance of it being unrepairable in the future compared to simple point to point. I don't know much about repairing pcbs but I would guess it is slightly more difficult.

Thanks for all the links I'll have a look. I did a quick google but wasn't really sure what to look for, I was mostly searching to see if there were any boutique brands building handwired point to point SS or hybrid amps but didn't see any as such. Probably just need to look harder.

thanks all
I personally rather like working with PCBs (especially the roomier ones). But looking at from a repairability pov it depends what fails. If a discrete component with a readily available replacement fails it's pretty repairable. If the something has caused a trace to fail it gets more complicated. In terms of design and manufacturing a PCB usually represents several iterations of refinement to get things right and once that is captured it can be produced in volume (and this is a good thing). The advantage of P2P, eyelets, perfboard etc is that the cost of modification is low - the process is fluid. The tradeoff is that manufacturability is also low. For a hobby builder this is a good trade. For someone wanting to sell amps... depends. The idea of a boutique SS amp builder kinda makes me smile.
 

totterer

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The advantage of P2P, eyelets, perfboard etc is that the cost of modification is low - the process is fluid. The tradeoff is that manufacturability is also low. For a hobby builder this is a good trade. For someone wanting to sell amps... depends. The idea of a boutique SS amp builder kinda makes me smile.
After building 2 tube amps and really falling in love with the old tweed thing I really didn't see myself ever wanting to build a SS amp. These projects were expensive and a bit stressful because of the risk involved with high voltage and just the frustration in the troubleshooting phase, along with the investment of money and time. I built the eyelet boards from laminate and sourced all the parts from various suppliers. By doing this I learned a ton, but just buying a kit would have been much easier.

I am incredibly glad I built them, and they work very well thanks to some help from the forum. I could not justify the investment for another amp project, but I caught the bug. I was thinking about building a pedal and I discovered the Fetzer Valve stuff. I started to wonder how close can you get to the old tube sound? I can say that pairing this basic concept, a well designed SS preamp with a class D power amp does get you in the ballpark. It is close enough for jazz if you will. This project was whimsical and just fun! I am already planning my next build. I used eyelets, because that is what I learned on and I like the look.
 

totterer

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I built it as a pedal first

IMG_0353.jpeg
 

El Tele Lobo

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I assume it's PCB, rather than hand wired or P2P, but the Henriksen Bud Six made me, a lifelong tube amp guy, a believer in Class D solid state amplification. It's not perfect (neither are the tube amps I've used...and I've used several), but it's pretty dang good. I'm pretty convinced a larger extension speaker cabinet would push me the reset of the way over for the Bud...but I'm mostly there already. My Champ has been turned on less than a half dozen times since I got the Bud 8 months ago.

I've owned, for reference, the following tube amps: Super Reverb Reissue, '63 Vibroverb reissue, Blues Junior, Pro Junior, a tweed Champ clone with a 12" speaker and a tweed Vibrolux clone. I've also played, in live situations, various vintage and reissue blackface (and a few silver face) Deluxe, Princeton and Vibrolux reverb amps; a '59 tweed Deluxe, a Hot Rod Deluxe and a Hot Rod Deville (and probably a few others I'm forgetting).
 

richa

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After building 2 tube amps and really falling in love with the old tweed thing I really didn't see myself ever wanting to build a SS amp. These projects were expensive and a bit stressful because of the risk involved with high voltage and just the frustration in the troubleshooting phase, along with the investment of money and time. I built the eyelet boards from laminate and sourced all the parts from various suppliers. By doing this I learned a ton, but just buying a kit would have been much easier.

I am incredibly glad I built them, and they work very well thanks to some help from the forum. I could not justify the investment for another amp project, but I caught the bug. I was thinking about building a pedal and I discovered the Fetzer Valve stuff. I started to wonder how close can you get to the old tube sound? I can say that pairing this basic concept, a well designed SS preamp with a class D power amp does get you in the ballpark. It is close enough for jazz if you will. This project was whimsical and just fun! I am already planning my next build. I used eyelets, because that is what I learned on and I like the look.
I think you can get an awesome sounding amp or pedal with SS. How much of the "vintage tube amp" you get probably depends on what part their behavior is important to you. I started my circuit building journey from the SS side with the goal of building something I liked and not necessarily trying to replicate any particular sound. But what that led to was wanting to understand what tube amps really do (and the more I learn the more I feel like a novice). There is very much a sense in which I want to eventually build some vintage character tube amps. But there's also a sense in which I want to do that to inform the kind of SS projects that also interest me. So maybe I am trying to replicate a sound. :)
 

Peegoo

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I think I meant point to point wiring really.

Sure. There are people that do it for the love of soldering and some of them do it to post pictures of their perfect stuff on Instagram--just like some welders tend to do.

Point to point wiring does not make something any better, stronger, or longer lasting than tagboard, eyelet card, or turret board construction. There's a reason why modern electronics is modular: it is much faster to produce, which makes it cheaper to make, and that cost savings goes into the wholesale price. And quality control goes up dramatically. Everybody wins. But just like any other manufactured item there is good quality and bad quality stuff in the market.

The thing many people forget is anytime you see a wire connecting one thing to another with soldered ends, chances are pretty good it was soldered by hand. Production robots can wave solder a pigtail with a plug on the other end and some can plug the other end into whatever it gets plugged into, but most times any wires connecting one portion of a circuit to another are hand assembled.

Pretty much the only time anything is done P2P is when prototyping a circuit on a breadboard or Veroboard. This allows easy changes and substitutions, but it's neither robust nor economical. If you've ever tried to suss out a circuit that's P2P, it can drive you nuts. Analyzing one and making repairs is not recommended for those that throw tools when they get frustrated :oops:

N09Jwqxr_o.jpg
 

philosofriend

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Those old Peavey amps are legendarily indestructible. My friend Jarad and his brother dropped one down a flight of stairs and didn't even bother checking it before taking it to the gig.
 

JeffBro

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On the topic of PCBs. Is the connection superior to the solder/wire?

I know there has been discussions about wire/gage/solid/stranded. And I guess the answer I perceived was that it matters what it's connecting to, or what amps/volts are flowing throw the wires.
 

sds1

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On the topic of PCBs. Is the connection superior to the solder/wire?

I know there has been discussions about wire/gage/solid/stranded. And I guess the answer I perceived was that it matters what it's connecting to, or what amps/volts are flowing throw the wires.
Are you asking about PCB traces compared to hookup wire? If so... both are just usually lengths of copper. In either case, the amount of copper used determines the current rating.
 

richa

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On the topic of PCBs. Is the connection superior to the solder/wire?

I know there has been discussions about wire/gage/solid/stranded. And I guess the answer I perceived was that it matters what it's connecting to, or what amps/volts are flowing throw the wires.
In both cases the connection is copper being joined by solder. At audio frequencies wire is wire pretty much wire as far as the signal is concerned (as long as it's big enough as noted above). Big enough can either be a matter of increasing current handling or reducing resistance (material in some aspects of the power supply). But layout is important (and critical in a few key areas). Hard to move traces around and see if it improves noise. Typically that is all worked out in the prototyping phase for a PCB (at least you would like to believe it is) because there ain't a lot you can do after the fact. Ease of handling is important. Suitability of the insulation for the voltage is important. It matters what you like to work with and what longevity you want out of it.

Edit: Length of run may or may not be less on a PCB. Depending on how many layers the board has sometimes you have to jocky a trace around quite a bit to get it where you want it. And there are not many places where resistance due to length is critical (not to say zero). Noise on the other hand...
 
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