lego's spin on Sluckey's AC15

[sluckey]

... but did Doug offer up the longboard version of this amp?

Yes.

http://hoffmanamps.com/MyStore/perlshop.cgi?ACTION=enter&thispage=TurretBoard.htm&ORDER_ID=!ORDERID!

Items 11, 12, 13, and 14. You can get the long board with or without wire pass-thru holes.

[TNblueshawk]

Steve, I don't know if it is work that blocks this or not but that link is giving me an error.
I shall poke around
 
Is it too lazy to not drill my own    I do like to do things from scratch but I'm also going to build my own speaker and head cab for it and danghat just takes me forever.
 
Edit: Found the board. Thanks.

[sluckey]

That link got mangled. Just scroll to the bottom of this page and click on the "Hoffman Turret Boards" link.

[TNblueshawk]

Man I found all kinds of good info housed since I was last on here. Great stuff and organization for this project. Will save me a lot of time now.
It's already been said but kudos to the groundbreakers here. Ed, Steve and Lionel.

[Ed_Chambley]

Steve, I don't know if it is work that blocks this or not but that link is giving me an error.
I shall poke around
 
Is it too lazy to not drill my own    I do like to do things from scratch but I'm also going to build my own speaker and head cab for it and danghat just takes me forever.
 
Edit: Found the board. Thanks.

Most of the time id doesn't matter if I build the board or not.  I am using a lot of terminal strips lately.  I don't think you will lose any of your "DIY Status" buying the board made by Doug.

I made the cabinets, chassis and head box.  On this one I really enjoyed making the board and along with Sluckey's description of the tremolo/vibrato really helped me understand the workings of the circuit, however there are a lot of holes.  Making the buss and ground scheme was fun as well.

Making the chassis was the least fun, but I am glad I did.  It was larger than necessary, but has allowed for me the do a few mods and keep the build very clean.  I have a LOT of amps and I cannot say enough good stuff about this one.  If I were to build another one I would plan for the Jump and Cascade switch as part of the build.  This gives you the EF86 and Wiggle together.

[TNblueshawk]

Steve, I don't know if it is work that blocks this or not but that link is giving me an error.
I shall poke around
 
Is it too lazy to not drill my own    I do like to do things from scratch but I'm also going to build my own speaker and head cab for it and danghat just takes me forever.
 
Edit: Found the board. Thanks.

Most of the time id doesn't matter if I build the board or not.  I am using a lot of terminal strips lately.  I don't think you will lose any of your "DIY Status" buying the board made by Doug.

I made the cabinets, chassis and head box.  On this one I really enjoyed making the board and along with Sluckey's description of the tremolo/vibrato really helped me understand the workings of the circuit, however there are a lot of holes.  Making the buss and ground scheme was fun as well.

Making the chassis was the least fun, but I am glad I did.  It was larger than necessary, but has allowed for me the do a few mods and keep the build very clean.  I have a LOT of amps and I cannot say enough good stuff about this one.  If I were to build another one I would plan for the Jump and Cascade switch as part of the build.  This gives you the EF86 and Wiggle together.

Ed, best place/price for Hammond iron? What say you?
I may hit you up one day for a broke in Celestian Blue if you wanted to part with one 

[Ed_Chambley]

Steve, I don't know if it is work that blocks this or not but that link is giving me an error.
I shall poke around
 
Is it too lazy to not drill my own    I do like to do things from scratch but I'm also going to build my own speaker and head cab for it and danghat just takes me forever.
 
Edit: Found the board. Thanks.

Most of the time id doesn't matter if I build the board or not.  I am using a lot of terminal strips lately.  I don't think you will lose any of your "DIY Status" buying the board made by Doug.

I made the cabinets, chassis and head box.  On this one I really enjoyed making the board and along with Sluckey's description of the tremolo/vibrato really helped me understand the workings of the circuit, however there are a lot of holes.  Making the buss and ground scheme was fun as well.

Making the chassis was the least fun, but I am glad I did.  It was larger than necessary, but has allowed for me the do a few mods and keep the build very clean.  I have a LOT of amps and I cannot say enough good stuff about this one.  If I were to build another one I would plan for the Jump and Cascade switch as part of the build.  This gives you the EF86 and Wiggle together.

Ed, best place/price for Hammond iron? What say you?
I may hit you up one day for a broke in Celestian Blue if you wanted to part with one 

I used a Hammond PT I had on-hand and got a Mercury Magnetics dealer near me to order the OT for me.  Lego bought his and got a deal is some way.

I don't like to let go of Blues as I watch Craigslist for them all the time.  All I have are in-use.    I have tried a lot of speakers.  Greenbacks are my second preferred in this amp.  JBL's and Altec are great.  You really want a speaker that holds together since headroom is limited.  The Weber cali sounds OK.

As with speakers, different folks like different, but the amp is naturally bright.

[TNblueshawk]

I figured you'd hold em'. 
 
After reading your review I'm sold on the Blue. I'll just sell a few more pedals to fund one 

[lego4040]

Thanks for getting me back on this Thread Hawk. I need to read up and see if I missed any tweaking helpers.  You mentioned understanding tremolo circuits and I got this video update from Uncle Doug over in YouTube land. For me it's a must watch, I'm no electrical engineer and this fellow really has great tutorials. http://youtu.be/1kV2nz4-fXw

[TNblueshawk]

Ok, Sluckey, or whoever, I know there has been a ton of discussion on the iron. I've know you guys have sort of had your own iron and or sourced part or all. I really want to get this part right...well I want to get it all right...but you know what I mean.
 
Sluckey I was trying to copy your iron based off your pics of your build. Does this look right?
PT: http://www.mouser.com/ProductDetail/Hammond-Manufacturing/270FX/?qs=dhCoiiGcT1Imxl%2FtudqGgA%3D%3D
OT: http://www.mouser.com/ProductDetail/Hammond-Manufacturing/1650F/?qs=vcFyY%252bOcAyhL%2FRhxzLkwxQ%3D%3D
 
Choke, couldn't find it at Mouser: http://www.digikey.de/product-detail/en/193B/193BHM-ND/459383
 
 
 
 

[sluckey]

Sluckey I was trying to copy your iron based off your pics of your build. Does this look right?

Why look at pics? There's a transformer data sheet in the documentation file. AES has all that iron and also has better prices than Mouser.

[TNblueshawk]

Sluckey I was trying to copy your iron based off your pics of your build. Does this look right?

Why look at pics? There's a transformer data sheet in the documentation file. AES has all that iron and also has better prices than Mouser.

Well to honestly answer your question I forgot I printed that part. I have stuff spread out everywhere and that got buried and I forgot you had that in there.   

[lego4040]

Hawk, there is a lot of wiring in this build so go slow. If your getting board from here make sure you do the wiring that goes from turret to turret first

[TNblueshawk]

Ok, getting my ducks in a row. I've got the board at least from Doug. I didn't feel like punching out my own for whatever reason...probably because I'll build my own head and cab and that is enough DIY for me on an amp build. I'll start a new thread soon on my build but I thought it more appropriate for one more question in this thread.
 
The only thing I'm stuck on really as to what I want to do mod wise is this jumping vs cascading the channels. I'm trying to get my head around the difference sound wise and the pro's and con's.
 
What are the positives and negatives of jumping, cascading or jumping AND cascading via DPDT sound wise? I know different strokes for different folks so I'm not looking for what sounds 'better' but what the difference in sound really is if that makes sense.

My mind is telling me that jumping in paralell where both are being played at the same time comes out in the wash and is the same as being cascaded or in series where both are being played at the same time? Different sound?
 
Thanks a bunch for any thoughts on this as I just can't decide and I guess I'm looking to be swayed.

[bonzerinc]

I just finished my build of this amp, and I'm really pleased with it. However, the normal channel is MUCH louder than the vibrato. I expected a pretty big difference, but nothing near what I'm getting. The vibrato channel cranked all the way could never be heard with a drummer in the room, but I can't even get the normal channel anywhere near full volume without feedback (and pain). When I run the 2 channels in parallel (jumpered) it sounds great- full volume and nice, rich tremolo. In series (cascade) the sound is really distorted and thin. One change I made to the circuit was to use a single input with a rotary switch to select between the channels and series/parallel. I've been over the switch many times, and I think it's good, but it would be my primary suspect if y'all say there shouldn't be such a big difference between channels. As it is, I'm really happy with either just normal, or the two in parallel, but would like the vibe channel to be able to stand on its own.


The switch positions are
1 normal
2 series
3 parallel
4 vibrato

In troubleshooting, I took the grounds of the two shielded wires straight to ground, bypassing the A pole of the switch entirely. Didn't help.

Thanks,
Michael

[lego4040]

I'm glad you dig this amp, Im just about ready to stuff it in the head SilverGun made for me. As for the volume issue, I have the same. It's just the way this amp is, run it In parallel(jumpered) for that boost, that's how everyone is doing it I believe. If you were playing in a place that has a PA system, that's were you'd get your more volume or in a studio you'd be miked. I like that switch setup you came up with. I have mine in cascade mode and I added the Swamp Switch. It's great for some real slow deep muddy Delta Shit.

[bonzerinc]

Thanks for the response, lego. I'll stop beating my head against the wall trying to figure out what's wrong with the Vib channel. Except that mine sounds awful in cascade, but great when jumpered.

This is just my 3rd amp build (plus a reverb unit), so I wasn't surprised when it didn't work on first start-up. I checked and re-checked everything, and it all seemed that everything was put together right. I was really getting discouraged- if everything's put together like I think it ought to be, and it still doesn't work, then I must not know what I'm doing. Then I happened to bump the speaker cable, and it made noise. I'd spent several days trouble-shooting the amp when a faulty speaker cable was the problem. Doh!

A good friend has been building the cabinet, and now we're down to quibbling over handle hardware and such. Once it's finished, I'll post some pics. I'm really pleased with the amp, and very much appreciate all the information I got off this thread. I've learned a lot about arranging a layout from the schematic, and am very impressed with the work done by lego4040 and sluckey on this particular amp. Much thanks to you both, and to the forum in general, for all the help. And also Uncle Doug, whose videos inspired me to pick this stuff in the first place. I was having trouble justifying another guitar purchase, but now that I have an amp addiction, too, the sky's the limit!

Sincerely,
Michael

[lego4040]

I love Uncle Dougs Videos, he Nails his videos. I want to copy all his videos to a disk so I'll always have them.

[TNblueshawk]

Thanks for the info Michael.
 
Interesing on the cascading. I wonder if others have experienced this as well.

[sluckey]

I didn't leave the cascade mod in my amp. I felt I could get a better sounding distortion using a pedal.

[TNblueshawk]

Thanks Steve. Maybe I'll just do the jumped mod then unless Ed tells me in hindsight he would not or has pulled his.

[Ed_Chambley]

I did not pull the mod, but I agree as is it does not sound very good.  I have my EF86 with it's own gain pot and I have lifted the bypass on the normal channel.  There is just too much crossover distortion.  Decisions, decisions, decisions, what to do.

Keep in mind I am using a 2 amp rig and using the Vox for my clean and overdriven amp.  I am using a 2, 10 Princeton for my wet amp.  Since I have it jumped all the time I can still use the Wiggle in the Vox, but for what I am doing (who I am playing with) the Princeton Bias Vary Tremolo works best.

I will say if I were going to use the amp by itself, I would only have the channels jumped since I really like the sound of the EF86 and the Vibrato in addition being able to control everything together is nice.

Sluckey is correct IMO about using a pedal for distortion as it helps the amp to have a big amp feel and I really like the way pentodes respond to boosting the signal.

[TNblueshawk]

Many thanks Ed. I've got what I need then on what to do. Jumped it is. I do plan to use on its own.
 
Sold my Fender HRD last night so today it's time to buy some parts 

[dbishopbliss]

I know its been a while for this thread but I figured I would ask here to keep thing in one place. 


1. Any recordings of this amp anywhere? I have seen links to other manufacturers, etc but I haven't found a clip to one of these.
2. What are the dimensions of the amp once its in a head cabinet? I have a Marshall 4x10 and a 2x12 that are roughly 24" wide. Will this board fit into a 24" wide head? I know it might seem silly but I don't like the mushroom look (big head on small speaker).
3. Any final thoughts on output transformers? Does the Hammond have the magic or do I need to invest in a Mercury?

[sluckey]

1. Any recordings of this amp anywhere? I have seen links to other manufacturers, etc but I haven't found a clip to one of these.

I haven't heard any recordings. Maybe Ed Chambley has?

2. What are the dimensions of the amp once its in a head cabinet? I have a Marshall 4x10 and a 2x12 that are roughly 24" wide. Will this board fit into a 24" wide head? I know it might seem silly but I don't like the mushroom look (big head on small speaker).

I used a 20x6.5x2.5 chassis with inward lips. Easy fit inside a 24" cab.

3. Any final thoughts on output transformers? Does the Hammond have the magic or do I need to invest in a Mercury?

I'm pleased with all Hammond iron in my AC15. I've only used Mercury on one build. I didn't notice any magic other than the disappearing money act.   

If you decide to build this please share your project with us.

[Ed_Chambley]

Here is the deal with the recordings.  I found a couple on youtube which show the type of Vox we built.  It is the EF86 channel that makes this amp and if the amp did not have Tremolo you would not notice the Vibrato is not as strong.  Listen to the video and you will notice.  The benefits to the build over the stock amp is the ability to modify things.  Jumping the channels simply allows the use Vibrato/Tremolo with the EF86 which makes it unique since the stock amp did not come this way.

To cascade the tubes you cannot just switch them in series as the distortion resulting is not way too much coming from a single stage.  If you intend to cascade switch the amp you will want to switch the EF86 to triode or reduce the screen resistor considerably.  Best to simply switch to triode mode.

Also, the problem with the original getting hot is resolved.  I can tell you I made many recordings of the amp along with other amps I have and computer uploads do not sound anything like the amp.  I do not put much stock in them.  The amp also has a feel you cannot record and the feel of an amp is where inspiration comes IMO.  Lots have asked for a recording and the one here is as good as any, but please understand even this video does not sound very much like playing the amp.

Speaker selection is very important with this amp since it is so harmonically rich even when playing clean.  You really don't want a speaker the breaks up easily.  I have and use a Celestion Blue, but it sounds great with a Altec 417 and a JBL 120, but like the Weber 12A150 breaks up and muddies the amps true distortion.

So far as the Iron you intend to use, I selected what worked best for me since I was building a head I wanted 4-8-16 ohm.  The guy that owns http://livinginthepast-audioweb.co.uk/index.php?p=xfrmrpp has a lot of information and knows a lot about Vox and even has the original iron.  I used a Mercury OT and a Hammond PT and the output tube plates with modern wall current stays at 300Vdc or very close.  To my ear dropping some of the voltage reduces the headroom and makes the transition from clean to distortion much more smooth.

Another thing you cannot record, which this amp is the best of any I have played, is the touch and the feeling of playing in compression and looseness.  The amp is very forgiving.  I wish I could get a recording to post that would do it justice, but you really just have to play one.

I used a 17 x 8 x 2 chassis and build a head box 20" x 9"deep and 8" high.  I always check a layout to see the chassis size I need then make it larger.


! No longer available

[Ed_Chambley]

Thanks for the response, lego. I'll stop beating my head against the wall trying to figure out what's wrong with the Vib channel. Except that mine sounds awful in cascade, but great when jumpered.

This is just my 3rd amp build (plus a reverb unit), so I wasn't surprised when it didn't work on first start-up. I checked and re-checked everything, and it all seemed that everything was put together right. I was really getting discouraged- if everything's put together like I think it ought to be, and it still doesn't work, then I must not know what I'm doing. Then I happened to bump the speaker cable, and it made noise. I'd spent several days trouble-shooting the amp when a faulty speaker cable was the problem. Doh!

A good friend has been building the cabinet, and now we're down to quibbling over handle hardware and such. Once it's finished, I'll post some pics. I'm really pleased with the amp, and very much appreciate all the information I got off this thread. I've learned a lot about arranging a layout from the schematic, and am very impressed with the work done by lego4040 and sluckey on this particular amp. Much thanks to you both, and to the forum in general, for all the help. And also Uncle Doug, whose videos inspired me to pick this stuff in the first place. I was having trouble justifying another guitar purchase, but now that I have an amp addiction, too, the sky's the limit!

Sincerely,
Michael

If you drop the voltage on the entire B+ where your power tubes are ~300Vdc as the original schematic, the 2 channels get a lot closer in volume or you can drop the voltage on the EF86 and the channels will get closer as well.  The EF86 increases headroom easier.

I have not noticed much difference in volume from channel to channel, but the vibrato is weak in comparison to tremolo.  I increased the gain on the Vibrato and no know why it is the way it is.  The vibrato begins to pump like an organ does and just doesn't sound very good.  Made me appreciate the Vibrato.  It does not sound anything like a Maggie.

[dbishopbliss]

I'm working on putting my BOM together... I know there is already one, but I don't think it includes parts for the mods so I'm hoping you can help out:


1. Brilliance Switch.  Do I need a shorting switch or a non-shorting switch?
2. Delta Tremolo/Vibrato. I cannot see a difference between the picture in the AC15 document and the MODS document. Are they the same or am I missing something?
3. Standby Plus! I see this is a 250R resistor... what is the wattage rating? Which switch would I need for this?
4. Where did you get those nifty solder lugs? (I think I asked this once before but cannot find the answer)
5. What are you using for ground bus wire? Looks heavier than standard 22ga.

One more thing... I have a set of Magnequest MQ565 output transformers that I bought for another project (Dynaco ST35) that I never built. They are 8K CT primary with 8 & 16 Ohm secondaries. Would it be stupid to use one of them for this project?

Thanks!

[dbishopbliss]

Wow... I'm getting old. I started re-reading this thread and realized I already asked most of these questions 2 years ago. Where does the time go?

[sluckey]

1. Brilliance Switch.  Do I need a shorting switch or a non-shorting switch?

I used a shorting switch, AKA make before break. If you use a non-shorting switch you will need a bunch of 5.1M resistors between poles to avoid popping.

2. Delta Tremolo/Vibrato. I cannot see a difference between the picture in the AC15 document and the MODS document. Are they the same or am I missing something?

Same. This mod was incorporated into my project from day one, although I initially used a toggle switch near the footswitch jack on the rear of the chassis. You can see that in this pic...

     http://sluckeyamps.com/VAC15/big_guts.jpg

3. Standby Plus! I see this is a 250R resistor... what is the wattage rating? Which switch would I need for this?

I have removed this mod because I needed that special switch in another amp. The resistor is 10W. Doug sells the switch. He calls it a Double Pole Single Throw but it's really a Triple Throw, AKA OFF-ON-ON.

     http://el34world.com/charts/SwitchDPST.htm

4. Where did you get those nifty solder lugs? (I think I asked this once before but cannot find the answer)/quote]Are you talking about those standoff turrets that have the grid stopper resistors and shielded cable attached? If so, those are military surplus. You can find them on eBay or buy them new at Mouser or other big retail distributors.

5. What are you using for ground bus wire? Looks heavier than standard 22ga.

That is 17 gauge steel electric fence wire from Tractor Supply Co. It's galvanized plated so you have to use flux for a proper solder connection.

Would it be stupid to use one of them for this project?

I'd probably use it, but then I have no plans of building a stereo amp. BTW, I chose to use all Hammond iron mainly because I scrapped my Lightning amp to build the AC15.

I did not like the cascade mod. Sounded too raspy to me.

[dbishopbliss]

I ordered parts and am planning out my build!


I have some questions about the ground scheme:


- Does the ground buss for the control panel connect to a lug on the right side of the chassis, or an insulated standoff?


- Why is there a NOR Gnd wire and a VIB Gnd wire? They appear to be connected to same ground buss. I assume there is an advantage to connecting both ends but I don't understand why.


Separate question about filament wiring (not specific to this amp):


- In the past when I have built audio pre-amplfiers, I have had to elevate the potential to reduce hum.  I don't think I have seen this on guitar amps, is there a reason?

[Willabe]

I've elevated the heaters on some of my builds to ~70dcv.

It takes 3 parts, 2 resistors, set up as a voltage divider off the main B+ and a small cap ~20uF @ 100vdc.

Look in here for good info;

http://www.valvewizard.co.uk/heater.html

[sluckey]

- Does the ground buss for the control panel connect to a lug on the right side of the chassis, or an insulated standoff?

There is an insulated standoff turret on the right side of my chassis. It is used only to support the end of the buss and does not actually connect to chassis.

- Why is there a NOR Gnd wire and a VIB Gnd wire? They appear to be connected to same ground buss. I assume there is an advantage to connecting both ends but I don't understand why.

Because the onboard NOR preamp ground buss does not connect to the onboard VIB preamp ground buss. So each separate preamp ground buss needs a separate wire to chassis ground.

Would you like to have your project in a separate thread or do you want to continue in this long thread? If so, let me know and also tell me what subject you would want to use. I can split off your posts and all replies to a separate thread if you like.

[dbishopbliss]

Because the onboard NOR preamp ground buss does not connect to the onboard VIB preamp ground buss. So each separate preamp ground buss needs a separate wire to chassis ground.

I swear I looked at the pictures and the diagrams at least 10 times and did not see the gap... suddenly its there.

[sluckey]

That's an easy one to miss. I think that has been mentioned before?

[bonzerinc]

If you drop the voltage on the entire B+ where your power tubes are ~300Vdc as the original schematic, the 2 channels get a lot closer in volume or you can drop the voltage on the EF86 and the channels will get closer as well.

I'm assuming you'd drop the entire B+ right after the rectifier, as with the off/on/on standby switch. If you just wanted to drop the voltage to the EF86, would you do that in the power train (R14, 22K 3W), or with the plate resistor (R15, 220K)? The schematic says the EF86 is getting 98V to its plate. About how much would you want to reduce that?

[lego4040]

Your going to love this amp, build was tedious for me being it was my third build. These guys here have been a blessing to me. I hope everyone here had a great holiday, I haven't been around lately, last six months have been interesting. I left my job and went back to work with old friends in another plant, had surgery to remove a tumor in my throat(benign)etc.....but got the itch again thanks to my sons desire to play guitar. I'll give him my 80's 59-U Dan electro and as a surprise I'm going to surprise him with the Hoffman Stout I built once I put a speaker in the cab.

[dbishopbliss]

I would like to build a variation of what Bonzerinc did, without the cascade.   I'm thinking I would rather have a single input and a switch to toggle (as opposed to rotary) between Normal, Tremolo & Parallel. I'm really bad with coming up with things on my own, but I am good at following diagrams. Could someone suggest parts needed and how to wire things together?

[sluckey]

I'm thinking I would rather have a single input and a switch to toggle (as opposed to rotary) between Normal, Tremolo & Parallel.

That's exactly what I did a couple months back. C&K make a good quality mini toggle that's perfect for this. Part # is C&K 7211. It's an ON-ON-ON switch. It's not a common switch in guitar amp circles but you can find it at big suppliers like Mouser.

http://www.mouser.com/ProductDetail/CK-Components/7211SYZQE/?qs=V0X8KZBlWwIZ97kF7byDEw%3D%3D

[Ed_Chambley]

If you drop the voltage on the entire B+ where your power tubes are ~300Vdc as the original schematic, the 2 channels get a lot closer in volume or you can drop the voltage on the EF86 and the channels will get closer as well.

I'm assuming you'd drop the entire B+ right after the rectifier, as with the off/on/on standby switch. If you just wanted to drop the voltage to the EF86, would you do that in the power train (R14, 22K 3W), or with the plate resistor (R15, 220K)? The schematic says the EF86 is getting 98V to its plate. About how much would you want to reduce that?

I would create a new node because changing the plate resistor will change the headroom of the tube.  In a practical application you may not even notice.  I just owned an original 63 model one time years ago back in the BM days.  BM= Before money and I had to sell it because it got too hot to be reliable.  Every time I used it, it seemed something got toasted.

I simply used a dropping resistor prior and my amp runs almost exactly like the original schematic which is what I wanted.  There is a noticeable loss of headroom, but I don't mind since I wanted a small amp.  I have other amps running 400vdc on EL84's.  I like those too, but IMO (and that is not worth much) I like the lower voltage.  There are benefits as tubes last longer, but from what I hear the JJ tube has no problems with 350, 360 Vdc.

[Ed_Chambley]

I'm thinking I would rather have a single input and a switch to toggle (as opposed to rotary) between Normal, Tremolo & Parallel.

That's exactly what I did a couple months back. C&K make a good quality mini toggle that's perfect for this. Part # is C&K 7211. It's an ON-ON-ON switch. It's not a common switch in guitar amp circles but you can find it at big suppliers like Mouser.

http://www.mouser.com/ProductDetail/CK-Components/7211SYZQE/?qs=V0X8KZBlWwIZ97kF7byDEw%3D%3D

I used a switch, but I use it in parallel all the time with all controls working.  If I want to hear the 12Ax7 I turn up that and it I want the Ef86 I turn up that.  I can mix them and I have that tremolo and Vibrato accessible all them time.  I found I never really turn the jump switch off and never switch out the slower tremolo.  If I built another one I would not even use a switch, I would parallel with one input jack add the swampy tremolo as stock, but the brilliance having multiple caps to me is a must have. 

I actually do not have any on the board.  They are all on the switch and I can go lower than stock, much lower.  I did get carried away with 12 different caps, but I really like the versatility.  I have since incorporated this into a lot of other amps I have as a mod to bypass the tonestack for increased gain, but still have switching tone control.

I cannot find the Reply where Sluckey told me how to do this, but you simply remove the cap that parallels with the brilliance switch and use it on the switch as well.  With the rotary switch straight up it is stock.   One click right it moves to the largest cap and the amp gets deep and from there it shaves just a little bass each time which results in what seems to be brighter due to loss of lower frequencies.

Playing Humbuckers on the neck with the largest cap makes for a great violin sustain.

[sluckey]

I cannot find the Reply where Sluckey told me how to do this

That's a curse of long threads! 

You know you read (or said) something but it's hiding in all the jibber jabber. I'll usually go back through a thread that's up to three pages long to hunt for details, but not a 15 page thread! If search can't find it then it's just lost to me. That particular detail is available on my website.

The brilliance mod is my favorite too, followed by the trem intensity and speed mod. And now I'm finding that I like the channels jumped. The only mod that I didn't care for was the cascade mod. I think it takes the AC-15 sound into the buzzsaw territory. I may remove all reference to that one on my website. 

[dbishopbliss]

I used a switch, but I use it in parallel all the time with all controls working.  If I want to hear the 12Ax7 I turn up that and it I want the Ef86 I turn up that.  I can mix them and I have that tremolo and Vibrato accessible all them time.

So you are saying that I can have one input and connect both wires from the 12AX7 and the EF86 to the tip of the input jack and use the volume knobs to "switch" channels. That might be even better... I'm don't care for a lot of knobs. And doing this will allow me to have tremolo on the EF86 channel? What's the downside?

[Ed_Chambley]

I used a switch, but I use it in parallel all the time with all controls working.  If I want to hear the 12Ax7 I turn up that and it I want the Ef86 I turn up that.  I can mix them and I have that tremolo and Vibrato accessible all them time.

So you are saying that I can have one input and connect both wires from the 12AX7 and the EF86 to the tip of the input jack and use the volume knobs to "switch" channels. That might be even better... I'm don't care for a lot of knobs. And doing this will allow me to have tremolo on the EF86 channel? What's the downside?

I cannot find a downside.

Wait until Sluckey posts as well.  He may know of a downside, but like I said I have it paralleled all the time.  Oh yea, change where the tremolo wire is connected shorting jack is as well or you will have a second of no tremolo when you switch it on as it takes a moment to begin to oscillate.  Simple mod, but a good one.

Sluckey, please explain this better, I am having trouble wording this correctly.

[Ed_Chambley]

I cannot find the Reply where Sluckey told me how to do this

That's a curse of long threads! 

You know you read (or said) something but it's hiding in all the jibber jabber. I'll usually go back through a thread that's up to three pages long to hunt for details, but not a 15 page thread! If search can't find it then it's just lost to me. That particular detail is available on my website.

The brilliance mod is my favorite too, followed by the trem intensity and speed mod. And now I'm finding that I like the channels jumped. The only mod that I didn't care for was the cascade mod. I think it takes the AC-15 sound into the buzzsaw territory. I may remove all reference to that one on my website. 

To cascade and get good tone you have to reduce the plate resistor and remove the bypass cap on the 12Ax7  and change the resistor to at least 5k6 value and increase the bypass cap value on the EF86, but them the clean tone is weak.  I will say either tube really responds well to a simple overdrive.

If you cascade like it is it is very brittle sounding harsh distortion.  Almost makes a sine wave look like a square wave it chops the top way too much.

I think I may have messed with this circuit to the point of be obsessed.    I absolutely love it tho.

[lego4040]

Two years this thread is! WOW, as a reply to post 714 I too have the cascade switch and normal channel is incredibly loud and tremolo channel is not. I'm gonna going to have to go back over previous threads and wiring to were I can just parallel it and use jumpers or change switch to the jumper. I use the Jumper on my recent 5E9-A build and the amp is incredible

[sluckey]

Sluckey, please explain this better, I am having trouble wording this correctly.

Move the FS to the wiper of the Depth control. See pic...

And here's a pic of my NOR-BOTH-VIB channel selector switch that uses a single input jack...