By master craftsman Pez.
Based on the Simple SE from Tubelabs.com
OK I'd like to immediately debunk my own title. First, this is not my first "DIY" project. I have done many simple things and a few
complex ones So this is not the first and definitely not the last DIY project I have done. It is however the first that I have ever done from beginning to end that wasn't a modification or someone else's project that I participated in. I (am very proud to say) built this amp with my own two hands. So what are my revelations? Well for one I have a much deeper appreciation for the actual sweat, blood, tears, and solder burns that go into making a product by hand and why they
must charge the sometimes exorbitant fees that they do. Yes parts cost for me was about $1100 (that's about twice as much as I originally intended to spend by the way)
Second there is nothing "simple" about this build. Yes it is simple if you have built an amp previously, yes it is a very simple schematic, yes anybody with a solid understanding of electrical engineering would say this is basic stuff. All that said, I am not an EE, I have very little if any understanding of circuit design, I can't read a schematic to save my life even after this build (I am learning though). In the scheme of things I will have to concede that this is indeed a simple design. So 'yes' it is simple and 'no' it is not. Are you still with me?
Ok back to the beginning. I wanted a tube amp to run my RM40s tweeters with. I didn't want to spend a lot of money so I started this
post hoping to do it on the cheap. This brought me to
Tubelab An excellent website for DIYers who are interested in starting their own tube amp. I wanted to build the Simple SE for around $400-$600 which I assure you is possible. I also assure you that it was far from likely for yours truly who just had to have the best everything.
So what does that include? Here's a parts list:
OVERSIZED Edcor output transformers CXSE25-16-5K (11lbs x 2)
Allied power transformer 6K7VG (7-8 lbs)
Giant Hammond Choke
Panasonic Electrolytics
Jensen Copper oil caps
ASC oversized supplemental power cap
oversized Hexfreds
high quality resistors were used throughout
goldplated ceramic tube sockets
Silver amalgamated copper wiring throughout
handmade (by me
) twisted pair super thin copper conductor signal cables with braided shield. (3 hours worth of construction in case you're wondering why so much detail)
RCAs are Cardas and the speaker terminals are pure copper/gold plated vampire wire.
Tube compliment is: 2 EL34 or KT88 and most equivalents, 1 12at7 for signal tube, and 1 5AR4 Rectifier tube.
Custom solid wood box.
Here's a take through of the project. After waiting what seemed like ages for my transformers, chokes, and caps to arrive I started assembly on the board. The toughest part of populating the board was putting all the caps, freds and CCSs on the back of the board while maintaining proper polarity. I thought building the board was going to be the hardest part, but it was by far the easiest.
Here's the top of the board:
Bottom:
The box deserves special consideration. My good friend Calvin Nogouchi built this box to my specifications. His excellent work can be seen
here The box is made of solid maple and Cherry wood. Calvin utilized a special dovetail like joiner on all corners which give the box a very unique look and it's sturdy. He also made the top plate out of 1/8" thick aluminum. In a word the box is gorgeous and absolutely one of a kind. It was the perfect thing to set the whole project apart IMO. (better pics at the bottom)
Configuring where I wanted all the parts.
Here are some pics of the holes getting drilled out. Not seen lots and lots of polishing, sweat, frustration and trips to hardware stores.
Tube holes and cap hole drilled out.
Then about 6 hours of fitting and slight tweaks to the holes drilled gives me a deceptively "finished" yet nonfunctional paper weight.
Hours and hours and hours of wiring.
Followed by a 3 day hiatus to keep from murdering someone.
Also repainted the cap rather than gaudy gold I went with Edcor blue.
Verified the wiring, cross my fingers and flip the switch.... Bingo! I got sound out of one channel! opened up the box again continuity test confirmed bad connection to signal cable. Fixed, turned on and it sounded like music!
I brought it over to Wayne to verify my work as well as give any pointers of which there were a few. He was kind enough to fix a grounding issue I had and redo my signal cable job. Big thanks!
Finally the finished product. Here it is folks, the Simple Truth!!!!
The back
I love how the tubes look like they're just sitting there on a clean metal surface!
Close up of Calvin's wonderful work.
In the makeshift burn in station.
I have been running it for a couple days now and no explosions or fires. (cross your fingers knock on wood etc etc) As a matter of fact it sounds very nice and looks nicer than any piece of equipment I have ever owned! It only has maybe 10 hours on it total, but it has a very robust midrange, smooth top end and images like crazy! I love the laid back yet powerful presentation it gives. It puts out way more sound than a mere 5-15 watts would have you believe.
I still have to wire it for triode/UL, cathode feedback, standby switch, optional solid state rectification, and cleaning up the wiring a bit but that is for a later date. I'm going to bring it around to some of the DAM members to play in their systems.
I have to say I have a new found respect for those who make equipment for a living. this is not an easy task, nor would it be something I could see myself doing day in and day out. It is a lot of love and a lot of pain that goes into something like this.
I want to give a thank you to mgalusha for helping me a bit with verifying some of the stuff on the board I wasn't 100% sure of. I also would like to thank my buddy Calvin for his beautiful wood work. This project would not be the same without it! But most of all I would like to give a big thanks to Wayne from Bolder Cables. Without your patience, drill press, and guidance I would not have been able to do this at all. Your feedback was crucial and I can not emphasize enough how lucky I am to have a friend like you. Be on the look out for a few select beers coming your way!
Thank you all for reading and please leave your comments.