lego's spin on Sluckey's AC15

[Willabe]

Looks nice!

I see you like red. 


             Brad     

[Ed_Chambley]

How far from the chassis edge did you guys center your 9 pin sockets?  They look a tad further away from the edge than I usually do.


Any specific reason to have the Leads from the Output Transformer short?  I am considering placing the OT further away since the laminates are vertical on both transformers.  I can just put them 90 and the choke at 45 degrees.  I am going to place the cap can in a different position.  Any reason not to put the cap can inside?  Just thinking out loud, but I am trying to decide what I a going to do about the short leads from the PT.


Sluckey, any specific reason for the DPST power switches?  Just had them on-hand or am I not seeing them correctly and they are SPST?

[Ed_Chambley]

Looks nice!

I see you like red. 


             Brad     

I am red headed (what is left of it) , but this material is fiberglass and I do have a dark red and blond theme working on this one.  Dark green is my favorite color, but I built an amp once using a lot of green and it looked sort of plain jane.  Your blue really makes a statement.  I like it.  Yours and Platefire where he used the blue and white.


After seeing Tubegeeks Canada, I thought of your colors and doing a USA amp.  Having star knobs and a Flag for grill cloth.

[sluckey]

It appearss you have 3 additional drill holes and I believe I will have one.

Ha. I was wondering if anyone would notice that. I had the board drilled and was in the process of loading turrets when my Xicons arrived. When I saw how small the Xicon 0.1s were, I made a hasty mod to my board to better accommodate some of those tiny caps. That left me with a few extra holes on the edge near the pots.

How far from the chassis edge did you guys center your 9 pin sockets?

1.25"

Any specific reason to have the Leads from the Output Transformer short?

No. Just keep them away from the preamp circuit.

Any reason not to put the cap can inside?

Not if you have room. Saves making a big hole.

Sluckey, any specific reason for the DPST power switches?

I only had two Carling SPST short bat switches. Those DPDT switches in the power section look like the Carlings from the outside. They actually simplify wiring the line side of the PT. If I had four SPST Carlings I would have used them.

[lego4040]

I got some reading to catch up I see, Ed I got those ceramic tube holders from TurretBoard.com. Sluckey I'll Check out your updates and make changes. I forgot to order the doghouse still, need to shop around first

[sluckey]

The cap board was sized to fit under Hoffman's small doghouse. There are a lot of different sizes available so be careful when deciding which one to order. Oh, and you will need short standoff spacers for the board, maybe even 1/8". Scrap pieces of 1/8" turret board make good spacers strips.

(C) Small Fender cap can cover
5.125" L  x 3.375" W x 1.375" H.

[lego4040]

Thanks for adding the update, I'll print out changes today

[lego4040]

Sluckey, What would be difference then the way Doug does his cap can grounding technique? Tearing shop apart and still cant find darn grommets

[sluckey]

I'm not sure what you mean. Got a link?

[lego4040]

My Bad, its the way he does his cap can grounding. He grounds all the Main caps into can then the can is grounded via screwed into chassis.
http://el34world.com/charts/filtercaps.htm

[sluckey]

That grounding scheme was used on the original 5F6A Bassman amp. That's the way Fender did it on that amp and Doug was just showing you how to do it. The dropping resistors are on the main board.

I personally don't like that ground scheme and will never use it. The main reason, I want the first input filter cap and the one for the screen node to be grounded at the exact same location as the PT HT center tap lead. That Bassman scheme requires a good ground connection through the screws holding the doghouse as well as a good ground connection for the HT centertap lead. It also relies on the chassis to carry all of the B+ current for the amp. I don't like using the chassis for a high current conductor.

Method #2 is what Doug uses for most of his amps and is much better.

[lego4040]

Thank you that explanation on the grounding, I have been hit twice by high voltage and had EKGs twice, not fun.

[lego4040]

I got around to cutting face plate and taping it on to chassis. I center punched the plate holes and will drill out. My back ordered pot should be here this week as well as my smaller stand offs and Cap can cover. I'll strip it down,deburr yadda yadda yadda and start assembling. My buddy who just bought a pos twin wants to buy this amp now 

[lego4040]

Ed, on the 9 pin spacing I kinda eyeballed it and made sure I had enough room on both sides. That Grey Mercury looks sweet, I looked at the Mercurys for this build but to $$$.

[Ed_Chambley]

Ed, on the 9 pin spacing I kinda eyeballed it and made sure I had enough room on both sides. That Grey Mercury looks sweet, I looked at the Mercurys for this build but to $$$.

I am not sure why Mercury puts those prices on their website.  I assume it is to protect their dealers.  Their products cost a premium, but they stand behind them.  If you have a problem with a transformer, they don't simply say you did something wrong.  IMO, theses things add value.  Over the years I have had 3 transformers bad.  Two were mercury and were replaced, but you could say since they cost twice as much it is no big deal. 
Anyway, the list price on the standup version I have is $215.00 which is 35% jobber and discounts for reordering the transformer cost me $118 shipped which is still high.  I got a local amp shop order it for me.    I send them a lot of business.  They say I am their top salesman.


I don't prefer Mercury for everything.  I like Heyboer for vintage Marshall and Marstran (sp?) for High Gain stuff.  Hammond simply makes great stuff and I have never used any of their Trannys that I was unhappy with.  I just wrote so many people on this and was confirmed this OT the vast majority to get that sparkle.  Here is hoping. 


So far, this is the most involved build I have ever done, but I have another which is close.  I am taking my time on this one and enjoying building it rather than pushing like I usually do.  I have put a lot of thought into this and it is coming together nicely.


EDIT- I have had more than 3 Transformers bad, but some were very old and some things I have bought with bad transformers.  What I meant is I have had 3 bad upon instillation.  Two were replaced by mercury and one simply told me no refunds or replacements.  That was a Weber, but I don't blame them.  It is their policy and you know it so crying is not allowed.

[SILVERGUN]

Here are a couple of photos of my board.

Ed AND lego,
I've been busy with my own stuff and not sure how I missed these great pics......somewhere along the line I stopped reading every post
BUT,
WOW, really nice work guys!!
Great informative thread and lots of good eye candy.....no detail has been left out.

Ed, your opinions matter to us, so please don't stop telling us why you do what you do. Even if you don't think it matters,,,, the details are in the details.

[lego4040]

Opinions and thoughts are very informative, I am hoping to be able to start soldering this coming week after I break it all down and go over it with a fine comb. I spent some time looking a cabinet options, this head is the 2ox6.5x2.5. Total lenght is 21.5 with the side ears, I like the Marshal look but realized this chassis is for upright(tubes up) so I might go for a unfinisihed head like Masrhsall's. Any adive and peoples past choices would be welcome

[SILVERGUN]

I spent some time looking a cabinet options, this head is the 2ox6.5x2.5. Total lenght is 21.5 with the side ears, I like the Marshal look but realized this chassis is for upright(tubes up) so I might go for a unfinisihed head like Masrhsall's. Any adive and peoples past choices would be welcome

I've been seeing these on Eb*y for a while, and it seems like a good price for good construction....can't vouch for it cause I haven't tried one
http://www.ebay.com/itm/British-style-head-cabinet-guitar-tube-amp-project-for-standard-chassis-/291133135398?pt=LH_DefaultDomain_0&hash=item43c8e31a26

EDITED__I missed the fact that it says it will only hold a chassis up to 19.5" with tabs....doesn't compute if the total outside width is 23",,,,but there must be something in the way, cause I'm sure the sides aren't made of 2x4's 

Looking closer at the zoomed in pic, you can see where there is a "cleat"(?) to mount the front panel......I "imagine" you "could" unscrew and remove the front and back panels and then notch that cleat out to fit your chassis.....but you will also have to modify the front panel control cutout so it doesn't interfere with your controls.
If you ask, he "might" do it for you 

[bnwitt]

Wow!  I disappear for awhile and a beautiful amplifier is born.  Thanks Steve for emailing me about this project and for all you have done to bring it to life.  I think I need to take a breather from the studio construction and the day job and build this little baby.  This is the second to last amp I wanted in my studio backline.  All I will have left will be the hand wired JCM2000 DSL 401.  I am really impressed with the layout and the build Steve.  Top notch work.  Lego4040 it looks like your build is coming out very nicely.  I've got the fever again.

[sluckey]

Glad to see you Barry. This is all your fault!   

[Ed_Chambley]

Yep, I would have to blame Barry.  Ever since I saw the darn thing I have not been able to quit thinking about it.  I will finish it shortly.

[lego4040]

  I'm not even done with this one and I'm deciding what next. I do my work in my shop desk during breaks but I'm bringing chassis home thus weekend to wire up heaters, that is of coarse sometime after kids soccer/doctors/dentist........ The faceplate fit like a glove too, whew. I have one hole left to drill once cap can comes in. I'm thinking about shooting back of chassis a color closest to plate. It looks boring now without it

[Ed_Chambley]

I'm not even done with this one and I'm deciding what next. I do my work in my shop desk during breaks but I'm bringing chassis home thus weekend to wire up heaters, that is of coarse sometime after kids soccer/doctors/dentist........ The faceplate fit like a glove too, whew. I have one hole left to drill once cap can comes in. I'm thinking about shooting back of chassis a color closest to plate. It looks boring now without it

Looking good.  If you install the chassis in a cabinet, it will look great.  Do the Dynmo Label like Trainwrecks.

I worked on my chassis.  Got everything punched and drilled except the faceplate.  I need to cut it and put it on.  I got tired and I usually stop when I do as I start pushing and don't do as good of a job.

I am looking forward to building the ground scheme and making the buss bar.  That is when I get to sit there and work in solitude and that is why I do this stuff.

I was supposed to get my cabinets back from getting them Tolex, but my friend got busy doing trim work to a car.  The nerve of that guy.
I did see them and they are most of the way complete.  They look great.  I wish I could do Tolex that nice.

[lego4040]

For the ground bus, did you get those mil-stand offs?  I looked at them in eBay again but there was less of a selection this time, I'm trying to come up with an alternative to that style. I never tried tolexing, my father used to reupholstery all our furniture, that was amazing. He could use a sewing machine like no other. I will also look at that labeler.

[sluckey]

Here's an alternative that works just as well. Look just to the right of the PT...

     http://home.comcast.net/~seluckey/amps/hammond/closeup.jpg

[lego4040]

That is a great alternative Sluckey, thanks. That label maker is sweet, do they sell clear labels? I was nervous as he'll cutting that plate and I can't believe I nailed it the first time. I screwed it to a scrap piece of wood and quadruple measured. If anyone is interested in label making powerpopguy over at BYOC created a awesome file theat you use with illustrator programs. Guys are making pro quality labels for their pedals that'll blow your mind. You need laserjet not inkjet, inkjet will run on clear photo decal paper

[sluckey]

Here's another alternative that works just as well. This one is 17AWG steel wire. 14AWG copper works well too. Only took 5 minutes to build, including time spent looking for the spool of wire and camera setup.   

[lego4040]

I do have a really good brother ptouch label maker

[lego4040]

Damn Sluckey that's brilliant, are you using those round needle nose pliers? If so what size? Cooper wire I have plenty of, 10,12 even 8awg in my shop.

[sluckey]

I used 4 1/2" round nose, but you could use a nail or even a screw to form a nice loop. Just make the loops before you bend to shape. I would not use #10 or #12 unless you have a big iron or gun. #14 works well and solder flows good with my Weller, but that #17 steel works great!

Look at this pic... http://home.comcast.net/~seluckey/amps/VAC15/19.jpg

I used a DYMO label maker with black on clear for those labels. I'm sure Brother will have plenty of clear tape in various sizes and colors.

[lego4040]

I need to go to Home Depot today  we're did you get that steel wire? Wait you mentioned a tracker company I think. I seen that pic, sweet. You used regular printer for the red back plate too you said I believe.

[lego4040]

So I had the day off yesterday for a Doc appt and figured I would get alot of the amp completed.  Landlord scheduled to have entire building shut down electrically for maintenence, so nothing got done

[sluckey]

I just replaced the brilliance switch with a 6 position rotary switch that selects different value caps. Much more useful than the single position ice pick cap. I used the same circuit that I have in my AC15 Lite.

     http://home.comcast.net/~seluckey/amps/hammond/hammond_ao39.pdf

[lego4040]

http://www.bigdguitars.com/install.html
http://www.bigdguitars.com/varitone.html
Sluckey this is what I have for a guitar I never finished, do you think I could use this? Or do I still need to put those resistors

[Ed_Chambley]

So I had a 12 position rotary on hand, guess what I did?  You guessed it, I installed a 12 different values, well actually 11, one remains stick.  May be overkill, but so.


I am actually getting a good bit done.  I am at the enjoyable phase as my chassis is complete.  I am installing my iron.  Won't be long till I am crying and complaining and troubleshooting.    I need to get some photos.  I have my cabinets and they look great.

[Ed_Chambley]

Some porn for ya.

[Ed_Chambley]

Here are a couple more.  Like I said, getting close to completed amp.

[SILVERGUN]

NICE!!!

So that's what an amp's supposed to look like? 

[Willabe]

So I had a 12 position rotary on hand,

Looks like a cap Gatling gun.     

Looks real good Ed! Cab too!


            Brad     
 

[sluckey]

Lego, without seeing a schematic I cannot say about that Tele switch. Here's the switch I used. You can eliminate those resistors by using this MBB (shorting) switch. I think even Radio Shack has these switches.

http://www.tubesandmore.com/products/P-H392

[sluckey]

Ed, whatcha gonna do with that ninth tube socket???

[Ed_Chambley]

NICE!!!

So that's what an amp's supposed to look like? 

My favorite amp is the 62 bassman you see behind, I also have the matching cabinet.  I have a 3 old 2, 12 bassman cabs.  Love the tone of them.  That cab has altec speakers in it, the original has the original speakers.  I cannot remember, they may be utahs.  Anyway, I will be using a Celestion Blue in this cab and I built it a tad wide to give me more resonance in a closed back.  I made the backs removable for 1/3, 2/3 rd open back.  There is 2 3" roundl removable ports on the front.

Since speakers and cabinets change/create the majority of the tone I like to have options.

This build has flowed nicely with Sluckey cutting the path.  Made it easy.  I have one thing to workaround and that is putting the cap inside.  SInce My chassis is 8" deep I shouldn't have any trouble.

Thanks for the kind words Brad.  See what your help over the past couple of years has done.  Really a lot of folks here on this forum.  I could have never built anything as nice as this if I had not became a part of this forum.  I would still be modding Marshalls and playing with radios.

Old Marshall circuits are simple compared to this thing.  I am still looking at the tremolo/vibrato schematic and scratching my head.  I remember how good it sounded.  I am trying to understand it better as I have a side build going in a Super Reverb chassis and I am thinking of putting this in the 63 Vibroverb circuit.

Back to work.

[Ed_Chambley]

Ed, whatcha gonna do with that ninth tube socket???

I have not completely decided.  I was thinking maybe 1 tube reverb.  That is why I wanted to put the main filter cap inside.  I am not going to do anything with it until it get the amp running stock.  In reality, it will probably never be used.  I do that often as it never hurts anything to have it, but it is awful hard to get one in there if you did not do it in the beginning.

What do you like best?  I am open to suggestions.  I don't think it needs an overdrive, but always thought a reverb would be nice in one of these.  Please make suggestions.

[Ed_Chambley]

BTW, the open tube will be between the ef86 and the PI on the normal channel.  I don't think this will cause any problems and will be the best location for potential future use.  I really don't see any advantages of doing anything with the Vibrato channel.  I don't think the results would be favorable.

If I do use it, it will have to be simple.  I need to see how much room I have when the stock amp is buttoned up.  I am not completely against a loop.  I believe I will have enough room for a loop or the 1 tube reverb.

Thoughts?

[sluckey]

Ed, I'm concerned about the location of your OT. It's right on top of the input jacks! That's courting with danger. The highest signal level in the amp is only an inch away from the lowest level signal in the amp.

If it were mine, I'd shift the choke and OT closer to the PT. Many successful amps (Plexi for example) have the OT mounted very close to the PT. I can't find any examples where the OT leads are close to the input jacks.

[Ed_Chambley]

Ed, I'm concerned about the location of your OT. It's right on top of the input jacks! That's courting with danger. The highest signal level in the amp is only an inch away from the lowest level signal in the amp.

If it were mine, I'd shift the choke and OT closer to the PT. Many successful amps (Plexi for example) have the OT mounted very close to the PT. I can't find any examples where the OT leads are close to the input jacks.

Well, it is certainly no problem to move it at this point.  I did not consider that, but the photo shows it clearly.  Marshall designs do not have the input jacks so close to the center.


Great catch as I was thinking about other things and the last thing on my mind was the location on the inputs.  My mind naturally considered them all the way to the right.  I will get me a little plug.  I will make it not noticeable as this is the nicest work I have ever done.


You think if I move it another 2 to 2.5 inches it will be good?  Is the wires or the transformer itself?  If the wires are the problem, I could use some mini conduit I use when I have 2 chassis and bring the OT wire into the chassis in an ideal location.


I am looking at a amp book I have and I cannot find an example done this way, but I cannot really find a layout like this one.


I just checked and I have a build where the OT is actually next to the PT with the choke last.  I do have a shield between them, but I removed it and noticed no differences in voltages or sound.


Now to more important stuff.


What would you do in a Vox with a whole 9 pin?

[sluckey]

Ed, this is how I was gonna do my iron...



But remember, I scrounged from my old Lightning. I would have had to splice too many leads so I finally just decided to keep the three pieces in the same layout as the Lightning.

Putting the OT right next to the PT has been successful with a lot of amps, including high end hifi stuff, such as this Dynaco Mark III...



Will your choke fit inside the chassis? If so, I would consider mounting it on the end right next to your dual can cap. Then rotate the OT 90° and about an inch away from the PT. Otherwise just mount like the Marshall clone shown above.

I don't have any ideas for the extra tube.

[lego4040]

Thanks for that tip Sluckey, I will look for it at RS around the corner. Ed those are beautiful , is that a standard Marshall plan?

[Ed_Chambley]

Lego, nothing about any of this build is standard.  If you are speaking of the cabinets, the interior size of the speaker cab is exactly 1/2 of a old bassman cab turned 90 degrees.  The headbox is much deeper since my chassis is 8".  I made the exterior of the cabinets look short, wide and deep to give it a contemporary look and used the colors to maintain a early 60's look since the amp is a 60's design.  Basically I have a marshall layout and amp look, a Vox circuit and a Fender cabinet and colors design.  I will be using Fender cream knobs.

Sluckey, thanks for the mention of the Dynaco.  I did not look at them I only looked at my marshalls with pancake pt's.  I have 3 dynacos and they are basically hum free.  Great design.  I will follow the Dynaco.  I cannot get the Choke inside.  My intention if I decide to do it is put a reverb in it.  I do not know if I will.  I have put a small board on top of the chassis and made a loop, but I don't know what I will like. 

First thing is play the amp stock.  I would just like some ideas because after a loop and a reverb, I am out of ideas since I have never done much with a EF86.  Merlin writes a lot about them.  Maybe I can get an idea there.

[lego4040]

Who is this Merlin I hear about from time to time? Is he some real amp guru magician? I must look him up on google