The cost I calculated does not include shipping. The Fender Champ actually uses four 5 cent rectifiers, five including the one for the power lamp, but let's not nitpick. If you could provide a parts list so that I can build one of these for $100 it would be most appreciated.
Transformers from Musical Power Supplies are no cost savings compared to Triode USA.
I just looked at a spreadsheet I did on a 5F1 derivative using a 6P1P, 6N1P, 6K49VG pwr transformer and P-T31 OPT. The total inculding "Moonlight" Tone control and Jewel lamp was less than $85 (excluding shipping). An Edcor XSE10-8-4K which sounds better only adds $5.
I used a SS power supply.
Most of the prices came from Antique Electronic Supply. Power transformer from Allied.
I'd be willing to bet Fender only has MSRP/3 in the Champ 600. Standard mark up is 3X from mfg cost to MSRP.
I used a SS power supply.
Most of the prices came from Antique Electronic Supply. Power transformer from Allied.
I'd be willing to bet Fender only has MSRP/3 in the Champ 600. Standard mark up is 3X from mfg cost to MSRP.
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That's not a 5F1 copy. A 5F1 does not use a 6P1P, 6N1P. The 6K49VG is the wrong voltage.
No, I think there is more variation between player then between genre. There are some very well know players on youtube. One counter example your statement is t a you tube video where Richie Blackmore is interviewed and he shows how he plays his (way to well known) Smoke of the Water riff. They have close up detail shots and he talks you through it. What's surprising is this is done "finger style" no pick with a light touch on the strings. He "lets the amp do the work" The most recognisable metal riff on earth and he does it with a playing style borrowed from classic guitar
Also on you tune is Joe Satriani himself showing how to play some shredding metal rifs and, same thing, a very light touch. In fact he says that lifting the fingers on and off each string makes so much noise (compared to his playing) that he mutes each string with right hand when he must move a fretting finger. The amp has such a huge gain that otherwise fretting a string would make a huge noise. He holds the pick with thumb and index finger and uses the other three fingers mute fretted but unplayed strings. Most ordinary humans can't do that at his tempo so they play louder to clover of the fingers on the strings noise but he says you can't play fast if you take time to dig into each string, so he goes light on the pick and mutes unplayed strings. No way can I do what he shows, Then he continues on about unconventional chord progressions an "F minor, g9 or something like that". Then tells his students to "just improvise over those chords and keep muting" and adds, "I can't do it if I have the think about it, needs to be automatic."
you tube is great, there are a lot of want-a-be types on you tube but if you look some well respected top musicians too.
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I didn't say copy, I said derivative.
B+ is close to 325V which is close enough to 340V which is what I've seen on 5F1 schematics.
I counted $7 for each tube which is close to what you can get JJ 6BQ5 and 12AX7 for.
So, the price is reasonable for what I've state.
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I have employed a lot of creative shopping. My spreadsheet says I can build a 5 tube P-P amp that makes about 10 watts in "cranked Marshall" mode for just under the $100 limit. That is way too loud for a practice amp, so there will be a built in "power soak". Anyone who has spent nearly 40 years as an engineer in a big company knows that a spreadsheet can say whatever you want, so I will start building it when all the parts get here. Tubes? Lets just say that the sockets cost more than the tubes.
Very true in the HiFi world. Not true in the guitar amp world. That lovely Champ left class A back in Kansas when you plug in a stomp box and ram a volt of input down its throat. Class A is a dream when the OPT saturates too.
If you build it the way Fender did in the 50's it will cost $$$$. If you use a 6AU6 driving a 6AQ5, use a N-68X, a cheap filament transformer, and a $13 OPT you can build it well under the $100 limit. With some creative re-engineering I can make a "Champ" for about $60 not counting cabinet or speaker. The little Champ transformer from Triode isn't to great either, its not much bigger than a 12AX7. It will saturate and force deviation from class A though, especially when you stuff a KT88 in a Champ. Don't do that with the stock Champ. You WILL smoke the power transformer.
A 12AX7 cannot be purchased for $7 in single quantities from any reputable dealer. If you have a source I would really appreciate knowing about it.
That's great. The amp looks great, and I'm sure it sounds great, but as you said yourself, and to my point, it's not a 5F1 copy and you can't build a 5F1 copy for under $100.
Does all this make it closer to a 5F2a (Princeton)? Not that it matters, the whole package looks like a good idea.
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Heck, at that price, you could even swing adding a low cost mosfet and the few related parts for VVR(Power Scaling) and still be on budget.
VVR and cathode biased amps
Then you are good from .5W to 4.5W and everything in between.
Hmm, a by no means definitive google search suggests that dollar price translates directly to sterling, £9.50 was the best I spotted over here. So it looks like " The £100 guitar amp challenge" if you're out of the US.
I think the term copy is being used as a general reference to the basic circuit topology rather than an exact rendition/clone/replica of the 5F1.
The two bigggest challanges I see are (1) if you want to hold real cost down you need to limit the number of stores you buy from due to shipping cost as George pointed out and (2) the transformer.
The biggest suppliers of transformers I'm aware of are Triode Elect, Hammond through various sources, Edcor and Allied with their own line of transformers.
The transformer will be at minimum around 25% of the total cost.
Granted, there are sources for surpluss transfomers that run a bit less, but the goal as I understand it is to have "over the counter" parts used.
Caps went up a bit since I did the spreadsheet. It will be close.
The biggest suppliers of transformers I'm aware of are Triode Elect, Hammond through various sources, Edcor and Allied with their own line of transformers.
The transformer will be at minimum around 25% of the total cost.
Granted, there are sources for surpluss transfomers that run a bit less, but the goal as I understand it is to have "over the counter" parts used.
Caps went up a bit since I did the spreadsheet. It will be close.