Look in the "Photo Gallery" thread for a bunch of pictures of how people built their amps. That is where I got the ideas I'm using in mine. It is a pretty basic layout that quite a few people have followed with success. That is why I chose it for my first amp build.
The Meng yue Mini is basically the same amp, but a commercially built one.
More power is usually not a cost issue until you get above the 30W range. Then the transformers start really getting larger and expensive.
For example the 30W pp Hammond 1645 costs $71 ea and weigh 4#ea. The 100W 1650R from Hammond weighs 12# and costs about $108 each so you have 24# of OPTs, plus the weight of the power transformer.
Single Ended (SE) transformers weigh more and cost more, (eg Hammond 1627SEA, 30W, is $129 and weighs 11.6#) because they have to handle the bias current of the output tube. They incorporate a gap to help control the flux and keep the size down but still are way bigger than PP transformers. In push pull the bias currents cancel each other to reduce the bias flux to near zero so the requirement for the cross section of iron in the core is lower. This is a implistic explanation, if you are into the theory read the thread on 'choosing an output transformer'. There are some really knowledgeable people who post here.
The Meng yue Mini is basically the same amp, but a commercially built one.
More power is usually not a cost issue until you get above the 30W range. Then the transformers start really getting larger and expensive.
For example the 30W pp Hammond 1645 costs $71 ea and weigh 4#ea. The 100W 1650R from Hammond weighs 12# and costs about $108 each so you have 24# of OPTs, plus the weight of the power transformer.
Single Ended (SE) transformers weigh more and cost more, (eg Hammond 1627SEA, 30W, is $129 and weighs 11.6#) because they have to handle the bias current of the output tube. They incorporate a gap to help control the flux and keep the size down but still are way bigger than PP transformers. In push pull the bias currents cancel each other to reduce the bias flux to near zero so the requirement for the cross section of iron in the core is lower. This is a implistic explanation, if you are into the theory read the thread on 'choosing an output transformer'. There are some really knowledgeable people who post here.
I think I'm going to go with your suggestions on El Cheap. I saved the schematic from the audiophiletalk.com, now will have to look into some parts, and stop going cross-eye'd looking at the schematics >,<
So if I'm reading this right this is the correct part list for "El Cheapo?"
http://pages.prodigy.net/jimmcshane/elcheapo.htm
Is there a package kit for the parts or do you guys source all the parts and then put it together?
So if I'm reading this right this is the correct part list for "El Cheapo?"
http://pages.prodigy.net/jimmcshane/elcheapo.htm
Is there a package kit for the parts or do you guys source all the parts and then put it together?
That link shows kits, but does not include the power and output transformers.
I buy parts from major suppliers, but I've been into electronics for many years (although only recently got back into tubes).
Newark, Digikey, and Mouser are primary sources for discretes like resistors, capacitors, etc if you don't buy the kits. For specialty parts like tubes, tube sockets, transformers etc, I use Antique Electronic Supply, but there are lots of other stores selling this stuff. AES is a one stop shop if you don't want to buy from multiple suppliers to save a few dollars.
Hammond makes good audiophile grade transformers as does Edcor (who sells direct, but doesn't list a 10W 10Kp-p transformer in the CXPP Series). These are not the"HIGH END" specialty transformers, but are probably as good as most audiophile transformers in the 70s. The Hammond 1609 10W 10Kp-p is specified from 20-20KHz I've got a pair and they are as good as the 70s Olson transformers I got off EBAY. There are less expensive transformers like the Edcor XPP10-8-8K that will have a narrower bandwidth (70Hz-18KHz), price vs performance.
I buy parts from major suppliers, but I've been into electronics for many years (although only recently got back into tubes).
Newark, Digikey, and Mouser are primary sources for discretes like resistors, capacitors, etc if you don't buy the kits. For specialty parts like tubes, tube sockets, transformers etc, I use Antique Electronic Supply, but there are lots of other stores selling this stuff. AES is a one stop shop if you don't want to buy from multiple suppliers to save a few dollars.
Hammond makes good audiophile grade transformers as does Edcor (who sells direct, but doesn't list a 10W 10Kp-p transformer in the CXPP Series). These are not the"HIGH END" specialty transformers, but are probably as good as most audiophile transformers in the 70s. The Hammond 1609 10W 10Kp-p is specified from 20-20KHz I've got a pair and they are as good as the 70s Olson transformers I got off EBAY. There are less expensive transformers like the Edcor XPP10-8-8K that will have a narrower bandwidth (70Hz-18KHz), price vs performance.
That's the correct URL for the parts kit. Mr. McShane went on a scrounging expedition to source decent parts, at modest cost. In addition to the parts kit, you need a chassis, and magnetics.
A good sized, 3 inch deep, rectangular, commercial baking pan, made from Aluminum, is a cost effective solution to the chassis question.
A full set of power magnetics can be ordered from Allied Electronics. Stock # 967-2343 is the Triad N-77U primary B+ trafo. Stock # 967-8019 is a Triad VPS24-1800 trafo, with a pair of "12" V. secondaries, 1 for heater power and the 2nd for B+ boost. Stock # 967-1004 is a Triad C-24X B+ filter choke. Stock # 227-0034 is the Allied 6K27VF B- and 12AT7 heater power trafo.
If possible, buy "clones" of the Dyna Z565 O/P trafo. Triode Electronics sells them for $78.95 each. At this time, the $47.13 Edcor model CSPP25-6-7.6K is the recommended budget O/P trafo. The guitar amp O/P trafo shown on the schematic has ceased to be a bargain.
Doesn't seem to be overly expensive to me. It'll probably be a long build for me since I'm learning everything from scratch as I go. Is there a link of a complete list of parts that are required for the El Cheapo? Or am I utterly blind and missing it.
I'm not terribly worried about chassis. The rest of my spare time is spent working on a drag car, so I'm very familiar with metal forming, and building. Probably go to local shop and pick up some nice stainless or something along those lines and make a nice chassis with wood sides.
I'm not terribly worried about chassis. The rest of my spare time is spent working on a drag car, so I'm very familiar with metal forming, and building. Probably go to local shop and pick up some nice stainless or something along those lines and make a nice chassis with wood sides.
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