Ok, firstly I think I'm a bit crazy and I might even make a complete fool of myself, but why not!
I'm a final year engineering student. The third year students are building a 50 Watt power amplifier(semiconductors) this semester. I'm giving assistance (demi), but why not attempt to design my own valve amp in the process?
I'm going to need a lot of research on this topic since the delicate nature of tubes. I dont have a valve amp so I thought its my next challenge. Valves isn't part of our course so its gona have to be all me.
Have any ideas or do and donts? I know I'm a complete idiot for trying this, but hey anythings possible :-)
Don't know much bought this
Mon, 2008/07/07 - 2:31am — ambientDon't know much bought this stuff so got no advise. But go for it dude.
Just be careful - A
Mon, 2008/07/07 - 10:33am — kaalJust be careful - A semiconductor amp usually can't easily kill you when not connected to the power outlet. A tube amp can. The voltages in a tube amp are by magnitudes higher than in semiconductor amps. (Both can kill you easily when connected to the power outlet of course).
Also, you can kill a tube amp easier as well by simply not connecting a speaker when turned on. A semiconductor amp does not suffer from that.
You will need more specialized equipment for adjustments, and parts will be harder to find and more expensive as well.
But - if you first think and then act, you will have lots of fun! You simply need to know what you do, and what you must not do. I'd actually recommend to "start small" (maybe with some valve-based pedals) to get some "smaller voltage tube-experience" before approaching a 50W tube amp.
Kaal
Thank you for that
Mon, 2008/07/07 - 11:59am — JacoThank you for that information, I'm real excited, but need to do my research and planning well. I've got no experience at all on valve amp design, but got few circuit diagrams of the AC30 TB and other 1960's valve amps. Dont know if its real but its also a start. I'll keep everyone posted and please let me know of anything that can help me. I dont wana die!:-)
I was tinkering with the
Mon, 2008/07/07 - 9:03pm — mself61I was tinkering with the idea to build a tube amp, you know a small simple one that has "the sound". I searched the net and found quite a few schem's for them but the cost is still higher than I wanted to pay, (just wanted to use spare parts from an old radio... lol) but there are some out there you might look into unless you have to figure it out on your own also. Good luck !!
www.selfdistruction.com
http://groups.google.com/group/tonelab-patch-exchange
I look at some prices on
Tue, 2008/07/08 - 11:36am — JacoI look at some prices on valves on ebay, dont know if I'm gona get it here in South africa!
Also its expensive! If someone have advice on where and how I can get my hands on them, please let me know. Wish I were in America or England cause this country makes me sad!
What really cost is the
Sun, 2008/07/13 - 1:02am — guitarmikeWhat really cost is the chassis and transformers. However you can build a basic amp for around 400 using top of line parts. For transformers I recomend hammond, dont believe the hype more expensive manufactuers hand out. You can get everthing you need from Antique Electronics. There are other sites as well, some maybe cheaper, but Ive delt with these folks and never had any problems. I repair vintage tube amps for a living and buy many parts, I wouldnt skimp, use resisters with power ratings as hi as you can get in the chassis, caps do matter, for coupling I like auricaps, find an amp you like the sound of, find the schematic, research the transformer info for impedence and voltages, the rest is easy. Trying to design an amp from scratch requires much more info than this, but I can assure, beside component value tweeks there havent been any "new" amp designs for many years. Yep, thats right. You got your vox, fender Bf types, and marshall which is a fender bassman with tweeks made. A soldano slo is a marshall with an extra gain stage and component tweaks, mesa and peavey copied soldano. I know Im kinda generalizing here, but basically this is true.
If possible I would like to
Sun, 2008/07/13 - 6:10am — JacoIf possible I would like to stay in contact with you, guitarmike. I've checked out some sites and put ads in local newspapers asking for old valve amps and cabs old or broken doesnt matter.
Im probably gona start when Im satisfied with the final design. If allowed is it possible for me to get your email adres? so I can ask stuff during my progres.
thanks
I sent you a message with my
Tue, 2008/07/15 - 6:04am — guitarmikeI sent you a message with my email, Ive bought many old el84 based amps, (this is the output tube) they are usually cathode biased and kick out about 15-20 watts. I personnally love these old amps, with a little bit of tweaking and maybe a few changes in the circuit design, you can have a very dynamic amp. With the volume down on the guitar, you can get a nice sweet clean sound and by rolling up the guitar volume, you can get a really nice crunch, kick in an od pedal and it will just sing. This can be accomplished with a minimum of volume change, and believe it or not, with a mic in front can give you all the volume you need for club gigs. My marshall is a 50 watt, and Ive never been able to crank it with out over powering the room with volume, and of course, tube amps sound best when ran hard. The poster who said be careful said it right, even in these low wattage amps youll find 300 volts or better. That is enough to kill you, so please, be very careful. I assume you are an electrical engineer, if so you should have the skills needed to build a very rewarding project. Soldering skills are important here also, a clean, well soldered amp with proper lead dress is essential. Check out aiken amps, there is a wealth of technical info there. Let us know how it goes.
Thanks a lot Mike, I'll let
Tue, 2008/07/15 - 9:26am — JacoThanks a lot Mike, I'll let you all know when I'm starting and how it goes, Its gona be my first project involving 300V +.
Thanks for all your time and information.
Hey guitarmike, I have not
Thu, 2008/07/24 - 1:36am — JacoHey guitarmike, I have not received your email message, I also send you one, but dont know if you got it.
I want to mail you some photo's of a old valve kit(old radio assembling kit) I got from someone, I'm not sure if this particular old valves will work in my project.
Can I give you my email address again or can you give me yours. It will be appreciated, I'm so excited and also found valve models for LT Spice which I'm using at the moment.
my email: 14409607@sun.ac.za
Thank you
Hi Haven't read the whole
Sun, 2008/07/27 - 11:45pm — sv-erikHi
Haven't read the whole thread through but here's a nice link if you are planning to build your own amp, there is something about safty too, read it carefully.
http://www.aikenamps.com/
Good luck
/Take care
Sv-e "Gibson SG user and lover :)"
hey Erik..... your picture
Tue, 2008/07/29 - 8:27pm — mself61hey Erik..... your picture is getting better all the time, was wondering where you been, nice to see your still with us.
www.selfdistruction.com
http://groups.google.com/group/tonelab-patch-exchange
The aiken amp site is a
Thu, 2008/08/14 - 9:18pm — guitarmikeThe aiken amp site is a GREAT source of info! read it and re-read it. Jaco is an engineering student (electrical I assume) so I hope he understands the safety aspects concerning a tube amp. If not, let me say most emphatically, there is enough voltage in a tube amp to KILL YOU. It is imperative that you understand basic electricity and electrical safety before under taking this project. Its also critical to have good soldering skills.
I did send an email, sorry if it didnt get there. Ill try again. I havent recieved one from you either, mikeboyette@bellsouth.net --- I did see the parts list you posted. In all honesty, I dont see a great deal there that will help. The caps and resisters, if the right value, could be used but these items are pretty cheap and I would suggest buying new ones. The first thing you need to do is find a schematic. Do a search for "tube amp schematics" and you should find many. Also search for "AX84". This is a site that has some real nice small wattage amp schematics and it is a community so youll find lots of help and advice there. Once you have your schematic, you can start collecting the parts you need.