lego's spin on Sluckey's AC15

[Willabe]

Looks real nice.


             Brad   

[TNblueshawk]

Who had that link to the mini chicken head knobs?

Lionel, I can't see the pics as I'm blocked at work but I jumped on for your question
http://www.smallbearelec.com/servlet/Detail?no=1190
 
Congrat's though. I'll check it out at home.
 

[lego4040]

I ordered 2 NOS RCA cleartop side getters 12AU7 and a NOS Japanese 6BQ5/EL84/7189 matched pair to try out on the amp. Im gonna order the cabinet and just might have to bite the bullet on that speaker Ed. I just got to refill my bank acct On another note I was going thru my box of parts and came up with these tubes, They came out of an old heathkit I know jack about tubes other then what Im learning now with you guys and my researching. These worth buiding into something? Maybe subbing into something?

[lego4040]

Thanks TN, did you start your build yet? thanks for the link.

[TNblueshawk]

Thanks TN, did you start your build yet? thanks for the link.

No man, funds are tight for the moment. I just got a new Jeep Wrangler a few months back and in a few months either I replace the stock shatty stereo system or I use that money to start to purchase parts. I commute about 1.5-2 hours each day to work so that car stereo just ain't cutting it. So this one may be awhile.
 
But, since 3 dudes got it fired up that totally encourages me that I could get it done.

[lego4040]

Doug is considering making this board available so you wouldn't have to make one yourself but that was part of whole experience

[g-man]

Deleted

[lego4040]

Ok Sluckey I'm gonna give that switch a go again because of your kindness. I completely took all parts of so its only switch again and will slowley give a go again. I did mine on a 21 1/2'' but you guys with lots of builds shouldn't have a problem. with the long board version and board over tranny poke throughs why not. Im not sure if board can or cant be over certain trannies tho. Someone is gonna have to do a cardboard mock up

[sluckey]

I know it was mentioned on the previous page, but is confidence level high that this would go in a 17" chassis? I would be interested to hear if anyone is trying it yet.

I would not attempt to put the long board version in a 17" chassis. But, the version lego built was designed to fit a 17" chassis. It would be tight and require a lot of planning, but it worked on paper and I believe it would work on a real box.

[sluckey]

Lego, post a closeup pic of the terminal end of that switch now that its stripped clean. I'll see if I can help. It really is a worthwhile mod.

[lego4040]

[lego4040]

  I got the rotary switch to work, you were right Sluckey, totally worth it.  I gotta blow some air and clean contact tabs, slight scratchiness.

[Willabe]

 

[sluckey]

I've compiled all the mods I have made into one file and put it on my website...

     http://home.comcast.net/~seluckey/amps/VAC15/Vox_AC15_mods.pdf

[kagliostro]

Very GREAT Job Steve 

 

Franco

[Ed_Chambley]

Bump!!

This thread is not done.  I am just having to take a break.  I have some new stuff coming after a while.  Least I hope so.

[lego4040]

If you just add the .022 if onto the board parallel to the .01 you'll get the swamp sound but does it effect the faster speed? I'd rather not have to buy another pot. Also Sluckey I seen in Merlin's book for adding a attenuator, It would be nice to be able to get the tube distortion at a lower volume.

[sluckey]

If you just add the .022 if onto the board parallel to the .01 you'll get the swamp sound but does it effect the faster speed? I'd rather not have to buy another pot.

However you add the cap will slow down the entire speed range. You won't be able to get that real fast trem. But, you may find a cap value that gives you a range that you prefer. Remember, the original only gave you a choice of 3 speeds!

You don't need the switched pot, I just thought that's a cool way to do it and if I were to build another, I'd get the switched pot. But look at my pics. You'll see that I installed a speed range switch right next to the footswitch jack. I used a DPDT switch just because it gave me a very convenient place to hang the cap. All you really need is a SPST switch.

It would be nice to be able to get the tube distortion at a lower volume.

I'm getting plenty of tube breakup at low volume, so much that I replaced my 12AX7s with 5751s. My low volume may be too loud for bedroom or apartment dwellers though!   

[lego4040]

I do love that swampness.

[dbishopbliss]

I just scanned this thread, but I didn't see any sound clips.  Has anyone recorded this thing yet and posted clips for us to hear?

[lego4040]

I got some new old tubes to throw in from the early 60's clear top for the wiggle channel

[sluckey]

I tried a little experiment today. I cascaded the NOR preamp into the VIB channel. Plenty of tube distortion that can be dialed back with the guitar volume control. You guys should give it a try to see if it's worthwhile. It sounds good to me but I don't trust my ears. Easy to do.

Just disconnect the wire from the wiper of the NOR volume control. Now connect a jumper (I used a gator clip lead) between the NOR volume control wiper and the tip of the VIB input jack. Put a 'dummy' 1/4" plug in the VIB input jack and plug the guitar into the NOR jack. Start pickin' and twiddle the knobs to suit.

I also cascaded the VIB into the NOR channel but didn't like it as much. If you guys will try this and let me know if you think it's worthwhile I'll draw up a mod to make it switchable.

[Ed_Chambley]

Been doing it since I built it.  It is only good normal to vib as mentioned. Surgery done and I cannot do much today.  It went very well as the Surgeon said.  I have some recovery time so I am learning to use a USB Microphone Mixcraft on Windows.  I have been using Pro Tools for a long time, but just too much for recording an amp so you can hear it.

You are liking the AS15 aren't you?  I knew you would.  Did you get the cab you are drooling over.  Makes a huge difference running a Blue.

[lego4040]

  I'll give that a try after I listen to the tubes I swapped out. Been busy w work and revibe, will post progress pic

[floyd]

You lovers need to book a room.. you remind my of a guy who just works on  race cars , because he's afraid to drive them himself.

[sluckey]

You lovers need to book a room.. you remind my of a guy who just works on  race cars , because he's afraid to drive them himself.

Interesting comment?

[lego4040]

Hey Sluckey how about putting that mod into a switch? Maybe put it on the back panel

[sluckey]

I recommend putting the switch on the front panel between the input jacks. That will keep all wires short.

[lego4040]

Shorter wires = less noise I brought board and parts home to work on it but I wound up going stripe bass/bluefish fishing and yesterday was a busy day as well as today

[lego4040]

Your getting rid of norm jack all together, hmmmmm

[sluckey]

Your getting rid of norm jack all together, hmmmmm

No! I simply removed the NOR jack and the VIB vol pot from the drawing since they were not involved in the mod. You will be plugged into the NOR jack whenever you want to flip the cascade switch.

[lego4040]

Ok makes sense, thanks for help

[Ed_Chambley]

You lovers need to book a room.. you remind my of a guy who just works on  race cars , because he's afraid to drive them himself.

Interesting comment?

I do not understand the comment.  I can say this thread is packed full of valuable information on a wonderful amp that few have have ever built and gotten right.  I can assure you the one I build it right on the money.  Open forums are just that and the coolest thing of all is no one has to read anything they do not want to read.

Thanks for continuing your thoughts and ideas.  These tidbits are really adding to the versatility of the AC15 while keeping the original in tact.  I would say this is a perfect mod.  If there are no photos or sound clips, it did not happen so the one I have does not make a sound if it falls in the woods.

[lego4040]

Ed hoes are those blue celestion holding up? I got side tracked with Sluckey's revibe build then I got side tracked with some health issues. Seems I might have the big "C" but if I do I have the best one. So my mind is not all in one place at the moment

[Willabe]

I do not understand the comment.  I can say this thread is packed full of valuable information on a wonderful amp that few have ever built and gotten right.  I can assure you the one I build it right on the money. 

+1, I agree.


              Brad     

[Willabe]

Is there a way to get a 2nd phase shift stage on the vibrato with out using another 1 1/2 tubes (3 triodes)?

The 1st triode splits the guitar signal into Hi/Low then the modulator (2 triodes) has the trem signal applied (dual phase from the plate and cathode) to it's grids and that's where the phase shift happens, right?

So to get a 2nd phase shift stage you'd have to split the guitar signal Hi/Low again and then feed it to another modulator tube?


                 Brad     
 

[Willabe]

Wait, what would happen if the signal from the modulator tubes plates was not mixed and sent to another modulator tubes grids?

Still would be a split Hi/Low signal fed to the modulators grids that are receiving 180 degree out of phase signals from the trem tubes plate and cathode. (Maybe the dual phase inverters trem signal would have to be flipped at the 2nd modulator tubes grids?)

Can't be that easy.

Maybe it can't be done at all with this type of vibrato circuit?


                Brad       

[lego4040]

You lost me

[Willabe]

The vibrato in that amp is true pitch shift.

More pitch shift stages sounds thicker.

Sluckeys 'Warbler' has 3 stages, some Maggi amps have 2 and some Maggie amps have only 1 stage of pitch shift. The old UniVibe SS pedal that Jimmi used was/is a 4 stage.

I built the Warbler and it sounds great to me. Very thick, full and lush sounding.


                  Brad     

[Willabe]

Look in here for a description of how 1 of the Fender versions works, 2nd to last page.

http://home.comcast.net/~seluckey/amps/misc/Amp_Scrapbook.pdf


                  Brad   

[sluckey]

The Vox circuit works more like the Warbler than the Fender harmonic vibrator.

[lego4040]

I'm waiting to hear back from a cabinet maker, he made my first cab and I wanted to give him first shot. I'm looking at putting it in a 5E5A TV front cabinet with the grills on top because of chassis build. He built one and has it on his gallery page and it's beautiful. I also swapped and put in some NOS tubes and had a issue? Wound up being that damn cap rotary switch. I put original switch back w 220pf and it's perfect. I put in a recommended 12au7 and was blown away. This is what I used. I am not tweaking another thing on this amp till I get cab and speaker. I am playing thru a sh*t speaker in a cardboard box at my shop and I gave it the How Soon Is Now Tremolo test and was floored

[lego4040]

Added the Swamp switch and really dig it in both tremolo and vibrato. My only thought is I'm not hearing any difference on depth between 1-4ish. The slowest hits about 4 and is great but no lower after that and vise versa

[lego4040]

Steve, what effect will the B+standby have in sound or tone? Is it to give me a cleaner sound at louder volumes? What kind of DPDT switch is it & wattage of that resistor? Also this combo off amp and Revibe is awesome, it would make an interesting project to combine the two, loose the tremolo section and use the Revibe tremolo and verb instead

[sluckey]

I don't hear any change in sound. Maybe if the amp was cranked up you would hear more sag with the lower voltage? Doug sells the switch. He calls it "Carling DPST Switch" and describes it as a "3 Position toggle switch used for Off-Standby-Play". I used a 10 watt resistor from my junk bin. Doug has the resistor also.

IMO this mod ain't worth the cost of the parts.

That revibe sounds great with a clean amp too. If you are really interested in an AC-15 lite, I highly recommend getting a Hammond AO-39 from eBay. Easy to convert and sounds just as good as the real thing.

[Ed_Chambley]

This is where I differ from Sluckey on the voltage.  I finally just kept the voltage dropped as the amp is not quite as bright and the cut control doesn't have to be turned up so much which in turn allows the amp to have a more open feel.  To me, when the cut control is too high the amp sounds a tad dull.  Also the amp breaks up by touch easier and is more forgiving since the attack is slower.  Of course everyone likes different things, but most all of the EL84 amps I have played are a tad ice pickey.  This one is not, even if the brilliance is very high and using single coil.


We all do like different things.  I absolutely love the wiggle in the AC-15 as it seems to complement the amp without overpowering it, but I have only heard clips of the revibe.

[lego4040]

Thanks for the feedback. I will save my few bucks on that mod then. I hope to pick up some boards this weekend for heads

[lego4040]

Oh Ed, you just hard wired your amp for the cascade or did you use switch?

[sluckey]

I would trust Ed's judgment about the sound differences with lower voltage. He still has good ears and a ton of experience concerning how amps sound. My hearing loss is a big disadvantage in the sound department.

For the past two weeks I've been playing all my amps thru a Weber 12" California mounted in a home made Leslie cab. I'm really liking that sound! And the Leslie cab takes care of the brightness of the Cali.

[lego4040]

Weber Cali? Need to read up on them Webers Again. All my big building is on hold, wife got laid off last month and doesn't start her new job till next week.