im looking too build a tube amp to power two small 5 inch speakers ,
and play records
i have little circuit experience i cant read plans , well sort of
any one know of any decent kits ,
diagram / part list and instructions
i want too spend under 100$ if possible
thanks
dave
and play records
i have little circuit experience i cant read plans , well sort of
any one know of any decent kits ,
diagram / part list and instructions
i want too spend under 100$ if possible
thanks
dave
Your $100 budget is too low. The magnetics alone cost more. The attached "El Cheapo" design should meet your needs. You supply case work of your liking. Jim McShane will sell you the requisite parts and tubes.
If the project whets your appetite, I'll provide references for power and O/P "iron", along with a thread (very lengthy) regarding its history.
If the project whets your appetite, I'll provide references for power and O/P "iron", along with a thread (very lengthy) regarding its history.
Attachments
Hi, Dave
With your budget you only spoil the first impression and do not want more to return to the tube sound.
If it were not for the budget, then I would recommend my Level Five Amp
just for another option, pick up an old console unit - that gives you donor iron and hopefully tubes. Cost will be anything from free to a quarter-ton depending on where you find one.
Then take a look at the range including RH84, El-Cheapo, the basic version of Baby Huey and Simple PP (or SE).
The design WILL be dictated by your donor, but at least you are over the bit of purchasing your major parts.
Beware - once you start, you are hooked.
Then take a look at the range including RH84, El-Cheapo, the basic version of Baby Huey and Simple PP (or SE).
The design WILL be dictated by your donor, but at least you are over the bit of purchasing your major parts.
Beware - once you start, you are hooked.
ill be playing records mostly
now i looked at the el-cheapo , and that looks perfect .
were can i find out how too read one and what all the b- and b+ go ?
ltp cathodes is
and the arrow/triangle
now i looked at the el-cheapo , and that looks perfect .
were can i find out how too read one and what all the b- and b+ go ?
ltp cathodes is
and the arrow/triangle
The LENGTHY saga of "El Cheapo" is here.
A complete set of power magnetics can be obtained from Allied Electronics. Stock # 967-2343 is the Triad N-77U primary B+ trafo. Stock # 967-8019 is a Triad VPS24-1800 2X "12" VAC filament trafo, which provides heater power to the 12AL5 and the O/P tubes, along with B+ boost. Stock # 967-1004 is a Triad C-24X B+ filter choke. Stock # 227-0034 is an Allied 6K27VF trafo that energizes the B- rail and powers the 12AT7 heaters.
As a cost containment measure, I suggest the $37.01 Edcor model GXPP15-8-8K as the O/P trafo. Used with triode wired "finals", as shown in the previously provided schematic, will yield a decent "6" WPC. Better (as in more expensive) O/P trafos will permit ultra-linear mode "finals", which will yield "12" WPC.
BTW, how deep do the 5 inch speakers go?
A complete set of power magnetics can be obtained from Allied Electronics. Stock # 967-2343 is the Triad N-77U primary B+ trafo. Stock # 967-8019 is a Triad VPS24-1800 2X "12" VAC filament trafo, which provides heater power to the 12AL5 and the O/P tubes, along with B+ boost. Stock # 967-1004 is a Triad C-24X B+ filter choke. Stock # 227-0034 is an Allied 6K27VF trafo that energizes the B- rail and powers the 12AT7 heaters.
As a cost containment measure, I suggest the $37.01 Edcor model GXPP15-8-8K as the O/P trafo. Used with triode wired "finals", as shown in the previously provided schematic, will yield a decent "6" WPC. Better (as in more expensive) O/P trafos will permit ultra-linear mode "finals", which will yield "12" WPC.
BTW, how deep do the 5 inch speakers go?
Right, I see now, 12AL5, rectifer tube 
I dont know, but theres a new Bottlehead kit with 2A3, looks sweet, cost more, and less output
I dont know, but theres a new Bottlehead kit with 2A3, looks sweet, cost more, and less output
LTP... that could be long tailed pair 😛
whatever it means, its probably connected to the 10Kohm CF(cathode follower ?), between the two 12AT7
I suppose the LTP Cathodes / CCS(constant current source) uses the B-
arrow/triangle is ground
if you study tube spec sheets you will find the numbered legs etc
but dont trust me too much on this 🙄
By all means. For all practical purposes, the 'AQ5 is a 'V6 in a 7 pin mini package. The big difference is g2 toughness and the 'AQ5 is more fragile. So, no parts value changes are needed.
Hi ampped,
By "records mostly" I take it you mean vinyl records. If so then your turntable cartridge will probably need a phono stage. You can buy chipbased ones quite cheaply or you might even decide to build a valve based one yourself.
Good Luck
Bill
By "records mostly" I take it you mean vinyl records. If so then your turntable cartridge will probably need a phono stage. You can buy chipbased ones quite cheaply or you might even decide to build a valve based one yourself.
Good Luck
Bill
I built a Fred Nachbaur SET amp based on the 13EM7 tube as a first build. It should be perfect for you. And accessible within $100. It is still an excellent sounding amplifier. With a thorough explanation at both basic and more advanced level. You need a couple of wall wart type transformers for power supply and some cheap Hammond output iron. (there is a Push pull version as well).
I use it as a office amp driving Tangband 4" fullrangers in TQWT boxes.
Here is how mine turned out
I use it as a office amp driving Tangband 4" fullrangers in TQWT boxes.
Here is how mine turned out
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