It's been a while (8 months?) since I got a schematic from Mark for this amp that he designed and finished the first version of this amp (1*10 eminence alpha10a) which looks like this
I've been fine tuning it and swapping the components & the speaker to eminence legend 1028 and gigging with it for awhile until a few weeks ago that I decided to go a bit further and make another cab for 2 tens that I've already got so the amp now has 1 eminence alpha10a & 1 legend 1028 in it and I'm pretty happy with the result so far..the amp now has EH 12ax7 and 2 Tung Sol 6v6s in it (I prefer nos Brimar 12ax7 with 1*10 though) and here's how it sounds.
all I wanna say is thank you to Mark Burness for being very generous with the design & informations & tips and everything. I am really lucky with my first project and with a few more tweaks I'm pretty sure that it'll be even better.
More pics & clips to come (if I have time - hopefully) and any comments/suggestions on the amp's tone is more than welcome. Thanks.
The amp sounds great. Well done, you did a good job building it. You should be rightly proud of your accomplishment Puri. I'm sure Mark will see the bat signal soon and comment on your work.
Good work Puri, indeed you should be proud of yourself. ;-) You did all the hard work on your amp, I just drew some pictures...anything to avoid real work, y'know!;-). The circuit design is well tested, but there's always ways to tweak stuff to personal preference, so let me know if you have any more thoughts there.
Great job on the cabinetry (I hate wood working, it looks lke a Laurel & Hardy sketch when I try it, I get Mark Phillips at AF Custom Cabs to do mine, he does some great work too).
Thank a lot guys for all the kind words. I never thought that it would feel so good having an approvements from you guys in this forum who have tons of experiences on good harp amps.
Apart from Mark's help this amp finished by a crazy level of obsession! I didn't know why I was so believed that I could do it. I've never done any woodworking before - not even using hand tools let alone power tools but I wanted to do it so badly so I bought a jigsaw, router, router bits and a dovetail jig and self tought and the 1*10 cabinet was the first one that I finished. Since then I've built 4 cabinets so far and now I'm loving it!
@bonedog, yeah Mark IS the man! About the cab building I've managed to find a budget way to do it and pretty sure that you'll be able to do it too it's not much hassles to it actually. Here's what I've learned.
1. You don't need a big router, just a laminate trimmer will cover all the works just fine. 2. You don't need a good jigsaw, you only need it for rough cut, all the precise cut/straightening edge is better done with a router/trimmer & a trim bit. 3. For the dovetail jig look for "Dovetail Template Master" from milescraft on ebay. This set includes 3 router bits and it's cheap & effective and comes with an easy-to-follow manual. 4. Use a 3/4" thick planks, I prefer pine. 5. Use a 1/2" round over bit. 6. To save money on F clamps you can use a rope to tie the two opposite sides together when glued and then tighten it by twisting the rope using a wood stick or something like that, from my experience this works just fine. 7. some very useful information here
Hope I got you some cab building bugs!! If you want anymore information about anything regarding cab building I'm happy to help. I just feel like sharing/giving something back to the forum after what I've got. Cheers,
Danged nice cabinet work, Puri. Looks like you'll enjoy this build for years down the road. ---------- Ricky B http://www.bushdogblues.blogspot.com RIVER BOTTOM BLUES--crime novel for blues fans available at Amazon/B&N and my blog THE DEVIL'S BLUES--due out soon
Hi Arne, this is also my first time on electronics so apart from I like how it sounds I can't really tell you the reason why we(me & my buddy who guided me through this) did all this tweaks. Here's what we've done..
- The power resistors are wirewound cermets apart from that they're all metal films - Dale & Caddock.
- We've tried Allen Bradley for the Grid resistor but it caused a strange, non musical overtones between notes so we put the Caddock metal film there instead and in my opinion it helps the sound to cut trough the band quite well.
- First we used Orange drops for the .022 and .1uf caps but then changed both to .027 nos russian teflon caps. This to me is quite a big improvement, at this point when I was using just the alpha10a I could feel the sound through my feet and it was thumping the grill cloth when I play.
- To make it a bit brighter and cut trough the mix better instead of removing a 25uf caps (one of Mark's suggested mod) we bicapped this one with .033 Vitamin Q, this was also a good move.
- The last thing that we did was changing the coupling cap from .1uf Orange drop to .033 Vitamin Q
That's about it, like I said I don't know much about electronics at all but my buddy knew that I know my taste (he's a stereo tube amp geek) so he suggested that we start out by using normal/chaep parts and replace them one by one so we could tune it towards the sound that I like and it turned out to be a good advise, time consuming but I get what I like.
Anyway, I'm also sure that it would sound great without any of my tweaks if I use the proper/quality parts from day 1 as well, for me there're couple more to replace and hopefully that'll be the end of it.
Cheers and thanks for your comments, Puri.
Last Edited by on Jan 26, 2013 3:07 AM
