Author Topic: My Plexi 6V6 build (Read 23775 times)

EL34 · « **on:** February 10, 2015, 11:05:42 am »

I finished my plexi 6V6 build and it is a really cool amp
This thing is whisper quiet. No hum at all

I made a few changes here and there as the build progressed

The 330uf cap on pin V1 pin 3 was replaced by a 22uf bypass cap
That channel now seems to have a more useable tone and less mud.

The 40x20x20x20 multi cap plus a 16uf cap for the power supply worked out great

Pete might notice in the pics that I moved my rotary impedance selector switch down top the last hole and this is a way better way to go. Thanks Pete

Lots of stuff to cram into the stout Chassis but it all fit
The exact build sequence of how I added parts is on the build page here
http://el34world.com/projects/Plexi6V6.htm

The parts list is here
http://hoffmanamps.com/MyStore/catalog/PartsListIndex.htm

The PDF schematic and layout are here
http://el34world.com/Hoffman/files/Hoffman_Plexi_6V6-V2.pdf

The info on the library is here
http://el34world.com/schematics.htm#Plexi_6V6_build

The PDF BOM is here
http://el34world.com/Hoffman/files/Hoffman_Plexi6V6_BOM.pdf

This amp sings with humbuckers really nice but it also cleans up with single coils really nice
Here's a couple sound clips

Lead parts with a humbucker
The chord comping is two single coils, the middle position on the guitar
http://el34world.com/Misc/Music/files/Plexi6V6Demo1.mp3

Sound clip #2
Some clean chord picking and then some soloing over the top of that
http://el34world.com/Misc/Music/files/Plexi6V6Demo2.mp3

sluckey · « **Reply #1 on:** February 10, 2015, 11:19:12 am »

Looks good Doug. It's also nice to see you building so much stuff lately.

EL34 · « **Reply #2 on:** February 10, 2015, 11:30:31 am »

Thanks
Got to do it to make sure the build goes together properly for my customers
I make a parts list of all nuts and bolts, ring terminals, etc as I build and that all goes into the BOM

These Stout chassis builds are really fun
Such a great compact size

DummyLoad · « **Reply #3 on:** February 10, 2015, 12:28:11 pm »

beautiful build and it sounds marvelous!

--pete

EL34 · « **Reply #4 on:** February 10, 2015, 12:33:20 pm »

Thanks Pete
Hope to do some other clips soon

That rotary switch at the tail end worked out great
I just had to enlarge the .375 inch hole to .38 to get it to fit

DummyLoad · « **Reply #5 on:** February 10, 2015, 02:23:00 pm »

i like the layout. very compact yet serviceable.

are you going to add a pilot light?

--pete

mresistor · « **Reply #6 on:** February 10, 2015, 02:44:41 pm »

It's a really nice looking amp Doug. Is there a chance to hear it? Would like to hear how this amp sounds.

BTW I just got done drilling a 17x9x2 chassis for a single channel DR and that was not the funnest thing I have ever done. What would be cool for the SCDR is a marshall style chassis and the board reversed so it read in English and not Chinese.. :-)

DummyLoad · « **Reply #7 on:** February 10, 2015, 02:55:53 pm »

click the play button on the media player in the opening post.

--pete

EL34 · « **Reply #8 on:** February 10, 2015, 03:22:04 pm »

Quote from: DummyLoad on February 10, 2015, 02:23:00 pm

i like the layout. very compact yet serviceable.
are you going to add a pilot light?
--pete

yes, but I am going to make a face plate for it and so I would have to un-solder it

EL34 · « **Reply #9 on:** February 10, 2015, 03:22:48 pm »

Quote from: mresistor on February 10, 2015, 02:44:41 pm

It's a really nice looking amp Doug. Is there a chance to hear it? Would like to hear how this amp sounds.

see post #1
There is a sound clip link there

billcreller · « **Reply #10 on:** February 10, 2015, 05:21:03 pm »

Hate to show my ignorance, but what do the titles "Stout" , and "Plexi" mean ? Models of amps ?

I lead a sheltered life ya know....

mresistor · « **Reply #11 on:** February 10, 2015, 05:51:31 pm »

wow! How did I miss that clip? this little amp sounds pretty good. Nice bluesy sound. Great guitar playin' too.

stingray_65 · « **Reply #12 on:** February 10, 2015, 06:42:22 pm »

Quote from: billcreller on February 10, 2015, 05:21:03 pm

Hate to show my ignorance, but what do the titles "Stout" , and "Plexi" mean ? Models of amps ?

I lead a sheltered life ya know....

Hi Bill,

Stout refers to Doug's stripped down hot rodded 18W Marshall that he had several variations of and now sells a custom chassis for.

Plexi refers to a family of Marshall amps that featured a Plexiglas face plate.

Ray

EL34 · « **Reply #13 on:** February 10, 2015, 06:51:57 pm »

Quote from: billcreller on February 10, 2015, 05:21:03 pm

Hate to show my ignorance, but what do the titles "Stout" , and "Plexi" mean ? Models of amps ?

I lead a sheltered life ya know....

Good explanation by stingray above

EL34 · « **Reply #14 on:** February 10, 2015, 06:53:00 pm »

Quote from: mresistor on February 10, 2015, 05:51:31 pm

wow! How did I miss that clip? this little amp sounds pretty good. Nice bluesy sound. Great guitar playin' too.

Thanks, I only did a quickie demo from an existing backing track
I have been busy since then and hope to get back and explore the amp some more

hardhead · « **Reply #15 on:** February 10, 2015, 07:51:11 pm »

Quote from: EL34 on February 10, 2015, 11:30:31 am

Thanks
Got to do it to make sure the build goes together properly for my customers
I make a parts list of all nuts and bolts, rig terminals, etc as I build and that all goes into the BOM

These Stout chassis builds are really fun
Such a great compact size

perfect for so many builds

smackoj · « **Reply #16 on:** February 10, 2015, 08:16:26 pm »

Very impressive work DH. That is a rockin' beast in a small package.

EL34 · « **Reply #17 on:** February 10, 2015, 08:27:05 pm »

Thanks guys

EL34 · « **Reply #18 on:** February 11, 2015, 10:59:23 am »

The PDF BOM is done and here
http://el34world.com/Hoffman/files/Hoffman_Plexi6V6_BOM.pdf

EL34 · « **Reply #19 on:** February 11, 2015, 05:17:44 pm »

Sound clip #1http://el34world.com/Misc/Music/files/Plexi6V6Demo1.mp3

Sound clip #2
Some clean chord picking and then some soloing over the top of that
http://el34world.com/Misc/Music/files/Plexi6V6Demo2.mp3

tubenit · « **Reply #20 on:** February 11, 2015, 08:28:27 pm »

Quote

Some clean chord picking and then some soloing over the top of that

WOW!! That sounded incredibly good!! Very transparent tone. I loved the smooth transparent musically sweet overdrive on the soloing.

I'm quite impressed. Thanks for sharing it! Great build.

With respect, Tubenit

billcreller · « **Reply #21 on:** February 11, 2015, 08:45:10 pm »

That little package really sounds outstanding !

I don't play that kind of music, because I don't know how ! I just listen !

TIMBO · « **Reply #22 on:** February 12, 2015, 12:20:48 am »

ME TOO

EL34 · « **Reply #23 on:** February 12, 2015, 06:22:47 am »

Thanks guys

I am not sure which amp I like best now

The 18 watt stout is pretty cool but the Plexi 6V6 may be even cooler
Have to do a side by side test and see

tubenit · « **Reply #24 on:** February 12, 2015, 07:18:54 am »

Quote

The 18 watt stout is pretty cool but the Plexi 6V6 may be even cooler

Both great amps. My vote is for the Plexi 6V6 because of the transparency of the OD tone and how smooth the overdrive is.

With respect, Tubenit

EL34 · « **Reply #25 on:** February 12, 2015, 08:22:39 am »

I posted a comment over on TAG on just how different the amp sounds in person compared to what got recorded.

Mic placement and other recording diddy's can make the amp sound completely different.

In person it has that Marshall cut that just gets in your face

EL34 · « **Reply #26 on:** February 12, 2015, 08:24:54 am »

Quote from: tubenit on February 12, 2015, 07:18:54 am

Quote
The 18 watt stout is pretty cool but the Plexi 6V6 may be even cooler

Both great amps. My vote is for the Plexi 6V6 because of the transparency of the OD tone and how smooth the overdrive is.

With respect, Tubenit

I could take the same exact backing track and record with the Stout TMB since I have not moved the mic yet

tubenit · « **Reply #27 on:** February 12, 2015, 08:39:53 am »

Quote

I could take the same exact backing track and record with the Stout TMB since I have not moved the mic yet

That would be an interesting comparison, IMO.

With respect, Tubenit

Big_Mike · « **Reply #28 on:** February 12, 2015, 10:10:51 am »

What is the wattage output on a 6V6 plexi?

EL34 · « **Reply #29 on:** February 12, 2015, 10:17:32 am »

Got me?
I know that it is loud :)

I don't know if Steve measured his Plexi 6V6

tubenit · « **Reply #30 on:** February 12, 2015, 10:49:04 am »

The Plexi 6V6 (mine was cathode biased) I built many years ago was louder than the original Princeton Reverb I had.

I am guessing it was maybe 14-15 watts?

With respect, Tubenit

EL34 · « **Reply #31 on:** February 12, 2015, 11:19:17 am »

I just did the same clip with the Stout TMB

I'll post it in a bit

sluckey · « **Reply #32 on:** February 12, 2015, 11:28:00 am »

Quote from: Big_Mike on February 12, 2015, 10:10:51 am

What is the wattage output on a 6V6 plexi?

Mine uses JJ 6V6s and is idling at 19.7W (9.5+10.2). Never measured actual power. I believe it can hang with a Deluxe Reverb.

My plate voltage is 394V. Doug's should be less because of his PT.

EL34 · « **Reply #33 on:** February 12, 2015, 11:36:11 am »

I have mine biased at 25ma per tube and I have 401 on the plates with the Solid state rectifier

I may have to check it again
that was when i first fired it up

sluckey · « **Reply #34 on:** February 12, 2015, 11:52:41 am »

Your amp is actually slightly hotter than mine. I'm running 24/26mA @ 394V.

I used that same PT in my EL84 cat biased 18W amp with EZ81 recto. Plates were only 324. The EL84s were idling hotter than my 6V6s. Guess the combined recto drop and higher load sucked the PT down more than the Plexi 6V6.

EL34 · « **Reply #35 on:** February 12, 2015, 12:03:04 pm »

I will be measuring again so I can add all the voltages to the PDF documents

EL34 · « **Reply #36 on:** February 12, 2015, 12:04:49 pm »

Here's the same tune done with the Plexi 6V6 and then the stout TMB

I don't think I got the chord tone setup the same way in both clips because I had moved the mic for the Plexi 6V6 demo clip
I like the chord tone on the Plexi clip better but that is more mic placement in the recording

For the lead tone on both amps the mic is in the same spot

Plexi 6V6
http://el34world.com/Misc/Music/files/Plexi6V6Demo2.mp3

Stout TMB
http://el34world.com/Misc/Music/files/StoutTMBDemo3.mp3

tubenit · « **Reply #37 on:** February 12, 2015, 01:13:31 pm »

Well, I honestly think I like the Stout rhythm tone more. It's fuller sounding with more mids (I think?) than the Plexi which has almost a glassy tone to it.

However, I like the Plexi 6V6 overdrive tone much better. It's just a lot more transparent to my ears than the Stout. The Plexi sounds more of a pushed clearer overdriven tone and the Stout sounds more distorted to me.

Having said that, I would be pretty happy with either amp tone.

With respect, Tubenit

EL34 · « **Reply #38 on:** February 12, 2015, 02:46:19 pm »

The cool part about having two players on the same page is you can start both of them at the same time
Then you can pause each player one at a time to go back and forth for a good comparison

iregan · « **Reply #39 on:** February 12, 2015, 06:48:41 pm »

I think both sound fantastic in different ways- I could see switching it up between them all the time. Since they are so small they could fit in one cabinet easy enough and would bring twice the goodness to the party :)
I think I have to build both now.
Regan

EL34 · « **Reply #40 on:** February 12, 2015, 07:17:51 pm »

Ok, it's a Stout Chassis party

EL34 · « **Reply #41 on:** February 13, 2015, 08:42:37 am »

I just uploaded a new Plexi 6V6 PDF file
The voltages are now on the schematic

http://el34world.com/Hoffman/files/Hoffman_Plexi_6V6-V2.pdf

EL34 · « **Reply #42 on:** February 13, 2015, 09:07:23 am »

I forgot to mention yesterday that the Stout TMB in the clip had a solid state rectifier plugged into the socket
So the voltages were much higher

EL34 · « **Reply #43 on:** February 15, 2015, 09:04:44 am »

I finished up the Plexi 6V6 this morning by installing the face plate and the indicator lamp

EL34 · « **Reply #44 on:** February 23, 2015, 01:12:56 pm »

Here's my Plexi 6V6 is SG's cabinet

The stain is Vermont maple color
I sprayed Satin finish polyurethane over the flat stain

EL34 · « **Reply #45 on:** February 23, 2015, 01:48:56 pm »

Here's a few 3D renderings of what I could do to the front panel on my CNC machine

I kind of like the Top one with the circle in the middle

One design could have a depression with a Reversed engraved Faceplate or a backlit logo sunk down into a depression

The one with the small slots is nice also

MakerDP · « **Reply #46 on:** February 23, 2015, 05:10:32 pm »

I really like Panel 5.

Have you seen EL panels? One of those would look really neat behind the slots!

Willabe · « **Reply #47 on:** February 23, 2015, 05:58:06 pm »

Quote from: MakerDP on February 23, 2015, 05:10:32 pm

Have you seen EL panels? One of those would look really neat behind the slots!

What are they?

Brad

Willabe · « **Reply #48 on:** February 23, 2015, 05:59:26 pm »

I like #4 and #5, but #2 and #3 are good too.

Brad

EL34 · « **Reply #49 on:** February 23, 2015, 06:09:28 pm »

Quote from: MakerDP on February 23, 2015, 05:10:32 pm

I really like Panel 5.

Have you seen EL panels? One of those would look really neat behind the slots!

Not sure what that is?

I am leaning towards #5, but I have another idea based on that design
Instead of a circle, it would be an oval and slots on either side

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Author Topic: My Plexi 6V6 build (Read 23775 times)

iregan