HoSo 56

[purpletele]

I played with the Mini Bassman for quite a while and enjoyed it.  However, it's time to try Geezer's HoSo 56.  Since I started with a Wreck style layout I am sticking with it through this project,  so I am re-working the layout to be reverse.  This poor little circuit board is starting to look like Van Halen's guitar.

Finished the Control Panel drawings on Visio, pretty smooth!  It printed correctly so I wrapped it around my current faceplate and re-drilled a few holes.  I am going to print a new template and compare it to the recently drilled template for accuracy.  If all looks good I'll have Sandy Henry make a thin plastic faceplate.

Good start on the control panel, getting the hang of Visio.  Visio has some real great templates that have helped me tremendously very recently.  I used the time line template for a legal trial that I am heading into.  I also need to develop a time line for another personal legal issue.  Hopefully I won't have to use the Crime Scene template, which is pretty cool with shapes like splattered brains that you just drag and drop.

Just kidding about the brains, but I bet they really do create shapes like guns and brains for real crime scenes. 

[purpletele]

Busted my knuckles working through Visio to create a new reverse layout of Geezer's SoHo 56.

I probably put in 6 or 7 hours most of which was trying to understand shapes and stencils.  I have full access to Sluckey's Shapes and I worked through my board using the CC resistors with out written values.  I think that looks great, but I don't have ' Resistor' eyes that associates values with the color code.  I think I am going to start a new stencil of resistors with values on them.

It's a good start!  Been up all night.

[kagliostro]

Add the .vss files to your library

Ciao

Franco

[purpletele]

Add the .vss files to your library

Ciao

Franco

Well thank you Franco!

I'll incorporate your stash, I appreciate it greatly!

I'm getting a kick out of producing accurate and nice looking documents. 

Update:  Downloaded to be uploaded and integrated into the Luckey Deluxe Board!

Right on! 

[purpletele]

Made some progress on the HoSo 56 amp today.  Spending a lot of time on Visio, which is good.

[purpletele]

HoSo Update

I have been drafting and building at the same time which certainly isn't ideal, but I am logging the hours on the learning curve.

I am building the HoSo 56 in Reverse to accommodate the Wreck Layout.  I used a similar layout as the Mini Bassman, specifically with regard to placing the 8 uF 600V Cap on the board and the B+ jumpers.

The voltages in the power section look consistent but I haven't verified with other drawings yet.

Looks like I am blocking out the Pre-Amp section somehow and I can't see it.  I had been working in early morning hours so I may have been fatigued and completely missed an error.  Nothing is jumping out at me now, but it's time to take a break and eat.

Heater Harness is delivering 6.53 V

V1-1  .358 V
V1-2  0
V1-3  .003 V
V1-4  HT
V1-5  HT
V1-6  0
V1-7  .72 V
V1-8  .72 V
V1-9  .003 V

V2-1  .821 V
V2-2  .67 V
V2-3  0 V
V2-4  HT
V2-5  HT
V2-6  .82 V
V2-7  .82 V
V2-8  54 V
V2-9  HT

V3-1  42V
V3-2  27.2 V
V3-3  23.8 V
V3-4  HT
V3-5  HT
V3-6  307 V
V3-7  302 V
V3-8  68.4 V
V3-9  210 V

V4-1  44.3 V
V4-2  27,2 V
V4-3  238 V
V4-4  HT
V4-5  HT
V4-6  307 V
V4-7  302 V
V4-8  68.3 V
V4-9  220 V 

Visio is coming along pretty well. 

I appreciate any thoughts or suggestions.  This amp like most is an experiment until it gets designated as a player.  I am hoping I can get this to be is a great amp. 

BV

[purpletele]

Current Photos

[sluckey]

I have been drafting and building at the same time which certainly isn't ideal

Terrible idea! Walk, Don't Run. You'll get there faster.

1. You started with a proven schematic. Now make your layout agree with your schematic. I usually spend as much or more time doing this.

2. Once the layout agrees with the schematic you can start soldering.

If you don't follow those two simple steps you will likely end up in trouble.

Study your layout and schematic. You will likely find errors. I see one right off the bat. You have Node E tied directly to Node D. Node E should come from that 8µF cap. That 8µF and 2.2K/3W are doing nothing. Consider moving that 8µF to the end of the board, right next to V1 and the circuit it will feed.

As far as no voltages on V1 and V2, make sure you have a 4.7K resistor between Node C and Node D cap can. Now just follow the voltage (wire) from the Node D cap to each board turret it connects to. You will likely find a missing or bad connection, or even a connection to a wrong turret.

[purpletele]

I have been drafting and building at the same time which certainly isn't ideal

Terrible idea! Walk, Don't Run. You'll get there faster.

1. You started with a proven schematic. Now make your layout agree with your schematic. I usually spend as much or more time doing this.

2. Once the layout agrees with the schematic you can start soldering.

If you don't follow those two simple steps you will likely end up in trouble.

Study your layout and schematic. You will likely find errors. I see one right off the bat. You have Node E tied directly to Node D. Node E should come from that 8µF cap. That 8µF and 2.2K/3W are doing nothing. Consider moving that 8µF to the end of the board, right next to V1 and the circuit it will feed.

As far as no voltages on V1 and V2, make sure you have a 4.7K resistor between Node C and Node D cap can. Now just follow the voltage (wire) from the Node D cap to each board turret it connects to. You will likely find a missing or bad connection, or even a connection to a wrong turret.

Thanks Steve,

I know I got a little carried away, I'm sort of anxious to finish this amp since it's in it's 3rd iteration. 

But I do want this one to come out nice, or at least as a prototype for a nice clean build with a case etc. 

I think you gave me just what I was looking for to move forward a bit.

I am liking Visio, I got JoJokeo up and running as well.  I am still unsure if it is best to use your resistors or use Franco's with values on them.  I like the look of the CC resistors on the drawings, and I think it is good for the brain to keep that complex association sharp.

[sluckey]

I am still unsure if it is best to use your resistors or use Franco's with values on them.  I like the look of the CC resistors on the drawings, and I think it is good for the brain to keep that complex association sharp.

Use whichever you are more comfortable with. I grew up in electronics when you had to know the resistor (and cap) color code. It's firmly carved into my brain. So I prefer the color bands and will continue to use them. I also like the cleaner, simpler look of having the values written on the body if you can read them. And that simplifies the stencils considerably. Only need one generic resistor for each style, rather than a big family of color bands.

[purpletele]

Study your layout and schematic. You will likely find errors. I see one right off the bat. You have Node E tied directly to Node D. Node E should come from that 8µF cap. That 8µF and 2.2K/3W are doing nothing. Consider moving that 8µF to the end of the board, right next to V1 and the circuit it will feed.

As far as no voltages on V1 and V2, make sure you have a 4.7K resistor between Node C and Node D cap can. Now just follow the voltage (wire) from the Node D cap to each board turret it connects to. You will likely find a missing or bad connection, or even a connection to a wrong turret.A

Steve,

Can you put an eye ball on how I moved my 8 uF cap near V1 and modified my B+ connections.   The modified layout and logic make sense and appears to tie out correctly.  I hope I don't get this guy as a response.

I do not understand the note about placing a 4.7K resistor between Node C and Node D cap can.  I currently have a 2.2K resistor, are you suggesting that I need to double the existing value?  If so, why? 


The cool thing is that my drawing and my board are accurately close and I can make the move on the 8 uF cap just as shown. 

Thank you for any input

BV

{EDIT- fixed lost quote - PRR}

[sluckey]

Much better for the 8µF cap.

I do not understand the note about placing a 4.7K resistor between Node C and Node D cap can.

I didn't tell you to put one there. I asked you to make sure there was one there.

As far as no voltages on V1 and V2, make sure you have a 4.7K resistor between Node C and Node D cap can. Now just follow the voltage (wire) from the Node D cap to each board turret it connects to. You will likely find a missing or bad connection, or even a connection to a wrong turret.

I was trying to help you find the missing voltages on V1 and V2. Your drawing shows a 4.7K mounted on the can between nodes c and d. If that resistor was missing in the amp that would explain no voltage on V1 and V2. If you have voltage at node d directly on the cap, but not at V2 pin 6 then you have a broken or misplaced wire or underboard jumper.

[purpletele]

I was trying to help you find the missing voltages on V1 and V2. Your drawing shows a 4.7K mounted on the can between nodes c and d.

Ah!  I was confused by my own mistake.  That should have been a 2.2K resistor.  Which indicates to me that once I selected that resistor and placed it the value did not register in my mind.  I guess that solves the question of labelling resistors for my new Stencil.

Thanks for the eyeball

Update:

Easy surgery, fired up and jamming.   
First impressions are that it seems like it has a lot of tonal variation.  I suspect I should run the gain lead in a shielded wire, it seems a little noisy, but other wise very quiet.

That's a good feeling to start it up and play.  Now I can sleep before 3:00

[sluckey]

What did you do to correct the V1 and V2 missing voltages?

[purpletele]

What did you do to correct the V1 and V2 missing voltages?

The modification that I made to move the 8 uf cap to area above V1 and the correction of the B+ lead to the E node appears to have established solid voltages for V1 & V2.

Voltages soon, I need to work today.

BV

[purpletele]

Enjoying the HoSo 56

I like the configuration of the controls.  It can get real crunchy or you can clean it up quite nicely.

The amp has passed the usability test, I think its worthy of having a nice case and clean new chassis and board.

I am going to re-construct this amp in a new chassis and make the board and lead dress presentable and solid.

I have to admit that now I am curious how this amp sounds with EL84's.

BV

[tubenit]

I tried the HoSo56 topology with 6BM8's, 6V6's, ECL84's, 5881's, 6AQ5's and EL84's.   EL84's were my least favorite.

I am just not a fan of that tube.  I know others love EL84 amps and I've sure heard some nice YouTubes and soundclips of EL84 amps.

With respect, Tubenit

[purpletele]

I tried the HoSo56 topology with 6BM8's, 6V6's, ECL84's, 5881's, 6AQ5's and EL84's.   EL84's were my least favorite.

With respect, Tubenit

It seems that it could be really a high pitched tone with the EL84's.  I know you mentioned your preference on those tubes in that amp.

Maybe it needs just a little more brightness.  I used a couple of 100 pF bright caps on the PPIMV as recommended by another member. 

It is plenty bright when the trim is dimed and the gain is down.  It looses brightness when I start rolling back the volume.  That is why I wondered about the tube performance.  I don't know enough about the characteristics of the EL 84 vs the 6BM8's at lower volumes.

I think I will re-draw it with the filter caps on the main board and use the cap can for another project.

It seems like an attractive amp that my friends and I will use.

Jeff, I forgot to ask you, but Jojokeo had recommended that I remove the .01 Cap from the load resistor circuit.  He remembers that cap causing an issue with volume leaking when tuned down or off.  Does that ring a bell?

Maybe I need to increase the value of the Trademark Tubenit enhancement Cap?

[tubenit]

The EL84's always seem to have some high end hash/harshness in the amps I've played, owned or built.  I've seen so many threads of builders complaining about the same thing and trying all kinds of remedies to resolve this.  I got rid of every EL84 amp I've had and will never build another one.  I found the 6BM8's to be a much smoother tone, IMO. 

IF you are needing more brightness at a lower volume, then maybe just install a spst switch with a 250 cap (120p - 500p) on the gain (1st volume pot)?  You can try this carefully with insulated alligator clipped wires and different caps to figure out what you like.

Brightness can also be related to guitars, pickups and speakers.  I liked the Emminence Cannabis Rex quite well with the amp for a smooth tone.

The Enhance Cap won't add brightness.  It smooths high end hash.

with respect, Tubenit

[purpletele]

The EL84's always seem to have some high end hash/harshness in the amps I've played, owned or built.  I've seen so many threads of builders complaining about the same thing and trying all kinds of remedies to resolve this.  I got rid of every EL84 amp I've had and will never build another one.  I found the 6BM8's to be a much smoother tone, IMO. 

IF you are needing more brightness at a lower volume, then maybe just install a spst switch with a 250 cap (120p - 500p) on the gain (1st volume pot)?  You can try this carefully with insulated alligator clipped wires and different caps to figure out what you like.

Brightness can also be related to guitars, pickups and speakers.  I liked the Emminence Cannabis Rex quite well with the amp for a smooth tone.

The Enhance Cap won't add brightness.  It smooths high end hash.

with respect, Tubenit

I just finished a long session of noodling and trying different controls.

I think the amp is fine the way it is.  No need to over tweak things.  It sounds great in a whole bunch of different settings. 

BTW, I am trying a nice broken in WGS ET-65.  That's a nice speaker so far, the price is certainly right.  I also have the WGS 12 C/S to try.

I still need to check voltages and such.  Once I got the B+ straightened out then it started right up and I have been playing it since.

[tubenit]

That should be a great speaker for that amp!

Don't know if you are playing out in a band or not?   

One of the features I liked about the 56T  (HoSo56 with reverb) is how well it cut thru a band mix.  We had a really LOUD drummer,  keys, bass, several vocalists, acoustic guitar and the 6BM8 56T cut thru that mix really well.  The amp was mic'd into the PA along with all the other instruments.

Sometimes a great sounding amp at home sounds just OK with a band.  And sometimes an OK sounding amp at home sounds fabulous with a band. At least that has been my experience.

I think Geezer's HoSo56 is an amazing versatile touch sensitive amp!  I loved it.

With respect, Tubenit

[purpletele]

That should be a great speaker for that amp!

Don't know if you are playing out in a band or not?   

One of the features I liked about the 56T  (HoSo56 with reverb) is how well it cut thru a band mix.  We had a really LOUD drummer,  keys, bass, several vocalists, acoustic guitar and the 6BM8 56T cut thru that mix really well.  The amp was mic'd into the PA along with all the other instruments.

Sometimes a great sounding amp at home sounds just OK with a band.  And sometimes an OK sounding amp at home sounds fabulous with a band. At least that has been my experience.

I think Geezer's HoSo56 is an amazing versatile touch sensitive amp!  I loved it.

With respect, Tubenit

Mr. Tubenit,

I am going to rebuild this amp, do you have a layout that goes along with your schematic & FX?

I think it is a great home/studio amp.  I am leaning toward 'Billy' or Little Reverend as a name. 

I can get some tones very similar to Waitin on the Bus/ Jesus.  I can even get harmonics all over the neck.  Lot's of fun


BTW, this amp performs just as you described it.  Thanks for being the champion of the Geezer HoSo 56.  That is a cool amp!

[tubenit]

Glad you're liking the amp!  I think it's a really wonderful amp that's very enjoyable to play.

I can help you with a layout.  The one being attached to here is in an SCH editable format that I can easily change.

http://el34world.com/Forum/index.php?topic=17863.0

IF you're enjoying the tone you're getting, then I would stick with the schematic that you are currently using because the tone stack in the schematic in your previous post will significantly change the tone and probably move it away from the Billy G. tone.  The tone stack that Geezer used was more Marshally in tone. 

Regarding the VVR ..............  I used Dana Hall's VVR when I built mine because it was so easy to install and was inexpensive.  He no longer sells those so you'd either have to make it on a terminal strip or a tiny board ......... or find another source that sells them already made.

I think the VVR is very very useful for recording at home.   Having said that,  I've gotten to where I prefer the PPIMV for just playing at home or playing out. 

IF you will post your current schematic with accurate values,  I'll modify the editable layout to match it and add the mosfet cathode follower and the active FX loop.

And let me know if you're going to go with a VVR ......... OR the PPIMV  ................. OR both.

With respect, Tubenit

[tubenit]

There is a wealth of VVR info along with drawing and photos here:   http://el34world.com/Forum/index.php?topic=6899.0

There is someone in Europe selling a version of Dana Hall's VVR here:  http://www.ampmaker.com/store/VVR-kit-for-cathode-biased-amplifiers.html

I have removed VVR from several amps and replaced them with PPIMV.  My experience and current thoughts about VVR vs. PPIMV are this ........

I think VVR has been superior for recording at home or for super low volumes.  At modest "playing at home" volumes, I easily give the PPIMV the winning edge.  IF your PPIMV is set at 1:00 o'clock (slightly right of straight up) and you like that tone, then I'd stick with PPIMV.


Again, if you want me to help you ...........

1)  post a schematic of what you are currently using

2)  let me know whether you are going to use a VVR,  PPIMV or both.

[tubenit]

I am going to rebuild this amp, do you have a layout that goes along with your schematic & FX?

Does this mean that you are going to rebuild this amp in the same chassis .......... OR build another amp?   The reason I asked is because the layout I have won't fit the punch out of your chassis?

One thought would be to just use your current layout board and remove the tone stack off the board and install it on a terminal strip between the board and the tone pots.  Then with the freed up space on your layout board you could install the mosfet CF.  Then you'd use another terminal strip to hook up the FX wiring on V2b.

I don't know if you are aware of it, but Windows "PAINT" has a feature called "flipped" that is on the same click that "rotate" is.

While it's a hassle,  one can change the direction of the layout board 180 degrees and then use the PAINT feature to relabel component parts. Or one can reverse it and then simply use it as a guide to redraw an editable SCH version.

In other words, you flip the entire layout horizontally.  Then you go to each component label and then flip those horizontally or vertically as is needed.

IF you look at the attached layout ............. I did this to demonstrate.  I flipped the entire board and then began flipping component labels.  So you see some that are correct and some that are backwards.

Is your PT  270-0-270  with 125ma ?

Tubenit

[purpletele]

I am going to rebuild this amp, do you have a layout that goes along with your schematic & FX?

Does this mean that you are going to rebuild this amp in the same chassis .......... OR build another amp?   The reason I asked is because the layout I have won't fit the punch out of your chassis?

One thought would be to just use your current layout board and remove the tone stack off the board and install it on a terminal strip between the board and the tone pots.  Then with the freed up space on your layout board you could install the mosfet CF.  Then you'd use another terminal strip to hook up the FX wiring on V2b.

I don't know if you are aware of it, but Windows "PAINT" has a feature called "flipped" that is on the same click that "rotate" is.

While it's a hassle,  one can change the direction of the layout board 180 degrees and then use the PAINT feature to relabel component parts. Or one can reverse it and then simply use it as a guide to redraw an editable SCH version.

In other words, you flip the entire layout horizontally.  Then you go to each component label and then flip those horizontally or vertically as is needed.

IF you look at the attached layout ............. I did this to demonstrate.  I flipped the entire board and then began flipping component labels.  So you see some that are correct and some that are backwards.

Is your PT  270-0-270  with 125ma ?

Tubenit

Jeff,

My apologies, I woke up put on some shades and started playing.  Not kidding, great day in CA so far.

I am adopting a new set of spec's for my amps.  I really admire the way Dr. Z makes his chassis and cabinets utilitarian and I am going to 'Nick That Style'.  Peter Mather is making me a new Plum Tolex Head that will receive the Chassis that I had fabricated by Seaside.

I believe the chassis is 17 1/2 x 7 x 2.

I am going to layout the new chassis on Visio today or tomorrow.  So to answer your question specifically, I am going to use a new clean chassis that can be made into a combo or head.  I am going to layout everything in Visio.  The project will utilize the topography of the transformer and power switches on the left side.  I will be designing a new board with filter caps on the board. 

I want the documents to be as nice as the amp.


Clean Slate, No Restrictions!  I do not want to alter the tone stack at all!!

I don't use an FX pedal but my colleagues do, I think I will build it because it is there to build, and it might be of value.

PT   Edcor EM 0829  270-0-270 @ 125mA

OT Edcor EM-0830  15 Watt, 8K Primary.  4,8 & 16 Ohm secondary taps



I will certainly welcome any assistance and guidance.

I'll get crackin.   

BTW I do not know about the VVR and at this point I like the PPIMV quite well.  No need to change anything on the design.

BV

[purpletele]

Tubenit,


In reviewing the schematics for the FX loop I found myself bit confused.  I had not seen an amp with an FX level control, nor have i seen an amp with a Pot on the send and receive jacks. 

Is that something that you had developed specifically for your rig?  Very intuitive.

Not sure I need that loop, once again if it is marketable then I will include it.

When I am playing at home, especially with a Grind/Gain tone, I will only use a touch of Reverb and maybe a touch of delay.

If it's important to someone then I want to try it.

[tubenit]

I always play with a very small amount of either delay (most of the time) or occasionally a small amount of reverb.  I strongly prefer them be in the FX loop.  They are so much quieter for me in the FX loop and it allows me to have overdrive delayed or reverberd instead of overdriving my delay or reverb which sound muddy to me and loses some of the transparency that I am wanting.   Just a personal preference but a strong one for me.

The idea of using the cathode follower & tone stack on the 2nd gain stage as the FX send is not new to me.  I had someone suggest the idea to me and tried it and found out it worked fantastic for what I was doing. I've done it on several amps with success.  Later on, I found others had already discovered the idea (including Doug Hoffman using something similar on Marshall amps).  In my implementation, I was using a mosfet cathode follower which allowed me to use that 12A_7 triode for the return of the FX loop.

I don't think the mosfet CF and using the V2b for the FX return is superior.  It's simply a good sounding minimalist approach. There are some advantages of having a 12A_7 in both the V2 position (with V2b being the CF) and having a 12A_7 in the V3 (FX loop position) because you can shape gain stages using a 12AV7, 12AY7, 12DW7 (reverse one), 12AT7, 5751 or 12AX7.  I've used all of those at different times in an FX loop.

It should be noted that the "return" of the FX loop works quite well as a pre-LTPI master volume.

I also found out some pedals worked reasonable well for me with a passive FX loop including a Boss digital delay and a MXR Carbon Copy.  They don't sound as good to me as with an active FX loop though. 

You can have an FX loop with send pot, return pot and level pot.  OR you can have fixed values (resistors) in one or more of those and go that route.  There is ALOT of great information on the active on board FX loop in ARCHIVES here:  http://el34world.com/Forum/index.php?topic=10208.0

One of my amps has an 82k fixed resistor to ground in place of a return pot.  The reality is that I adjust the FX level somewhat frequently but the send and return levels are pretty much "set and forget" for me.

There is a solid state active FX loop that I've read many people claiming to be the most transparent they've ever tried.  It looks to be reasonably easy to install, so that could be an option for you.

https://store.metropoulos.net/collections/amp-mods/products/zero-loss-fx-loop-board-only

I have found the active FX loop to be useful with a graphic equalizer also where the EQ pedal has a boost feature.  The main thing for me with time effects is they add a noise at "idle" that I don't care for and they color an overdrive tone too much for my liking.  Again, it's a personal thing and my thinking and experience with it isn't necessarily "better". 

Unless you're recording alot at home ........... or need a volume that you could easily converse over with a normal speaking voice,  I think the PPIMV is a more useful option.  IF you need a volume that low, the VVR is hard to beat at that low volume.

With respect, Tubenit

[purpletele]

I always play with a very small amount of either delay (most of the time) or occasionally a small amount of reverb.  I strongly prefer them be in the FX loop.  They are so much quieter for me in the FX loop and it allows me to have overdrive delayed or reverberd instead of overdriving my delay or reverb which sound muddy to me and loses some of the transparency that I am wanting.   Just a personal preference but a strong one for me.

The idea of using the cathode follower & tone stack on the 2nd gain stage as the FX send is not new to me.  I had someone suggest the idea to me and tried it and found out it worked fantastic for what I was doing. I've done it on several amps with success.  Later on, I found others had already discovered the idea (including Doug Hoffman using something similar on Marshall amps).  In my implementation, I was using a mosfet cathode follower which allowed me to use that 12A_7 triode for the return of the FX loop.

I don't think the mosfet CF and using the V2b for the FX return is superior.  It's simply a good sounding minimalist approach. There are some advantages of having a 12A_7 in both the V2 position (with V2b being the CF) and having a 12A_7 in the V3 (FX loop position) because you can shape gain stages using a 12AV7, 12AY7, 12DW7 (reverse one), 12AT7, 5751 or 12AX7.  I've used all of those at different times in an FX loop.

It should be noted that the "return" of the FX loop works quite well as a pre-LTPI master volume.

I also found out some pedals worked reasonable well for me with a passive FX loop including a Boss digital delay and a MXR Carbon Copy.  They don't sound as good to me as with an active FX loop though. 

You can have an FX loop with send pot, return pot and level pot.  OR you can have fixed values (resistors) in one or more of those and go that route.  There is ALOT of great information on the active on board FX loop in ARCHIVES here:  http://el34world.com/Forum/index.php?topic=10208.0

One of my amps has an 82k fixed resistor to ground in place of a return pot.  The reality is that I adjust the FX level somewhat frequently but the send and return levels are pretty much "set and forget" for me.

There is a solid state active FX loop that I've read many people claiming to be the most transparent they've ever tried.  It looks to be reasonably easy to install, so that could be an option for you.

https://store.metropoulos.net/collections/amp-mods/products/zero-loss-fx-loop-board-only

I have found the active FX loop to be useful with a graphic equalizer also where the EQ pedal has a boost feature.  The main thing for me with time effects is they add a noise at "idle" that I don't care for and they color an overdrive tone too much for my liking.  Again, it's a personal thing and my thinking and experience with it isn't necessarily "better". 

Unless you're recording alot at home ........... or need a volume that you could easily converse over with a normal speaking voice,  I think the PPIMV is a more useful option.  IF you need a volume that low, the VVR is hard to beat at that low volume.

With respect, Tubenit

Thanks Jeff,

Let's just plan on using the system that you have for the FX Loop.

I don't like the chassis that I was planning on using, so I am going to make a new one during this design process.

Also, I can get another set of transformers if I need to boost the voltage to 290-0-290.  I can't bring myself to take apart Billy.  I think I'll get a new face plate and leave it in the raw state.

Chicks dig that décor!

[purpletele]

Voltages from Billy

The amp performed quite well all day

[tubenit]

OK, since you never provided a schematic for me that matches your amp,  ........... I've made a guess.  I've change my schematic to match as closely as possible what Geezer's had with a few minor changes.

Once you've confirmed your (not Geezer's) schematic, then I'll edit the layout to match what you have with the mosfet CF and FX added.

Do you use Geezer's relay switching or put that switching on a toggle switch?

Would you like to have a toggle switched mid-boost added?

I definitely would stay with a 270-0-270 transformer (or a 275-0-275) that has at least 125ma & use a 5Y3GT (old stock) rectifier. 

Do you have ExpressSCH on your computer?  If you have Windows and don't have ExpressSCh, please consider downloading this free program. 
https://www.expresspcb.com/expresssch/

With respect, Tubenit

[tubenit]

And if there are truly no restrictions and you don't need the "minimalist" approach using the mosfet CF, then I personally would prefer to build it this way. 

I like the V2 (2nd gain stage) and V3 (active FX loop) not sharing the same 12A_7 tube.  That way you can use a 12AX7 or 5751 (my preference) in V2 and then a 12AY7 or 12Dw7 or 12AT7 in the FX loop.  I find the 12AY7 seems to do well at preserving the tone of the preamp without adding much in the way of gain.  It just allows a little more gain and tone shaping, IMO to have the 2nd gain stage and FX not share a dual triode. 

I also personally like the midboost feature which is used on the Dumblish style amps and some Mesa Boogie style amps.  IIRC,  Geezer wasn't that fond of the midboost cap in the tone stack and preferred another route, but I did like it and found it useful.

I'd probably build it with the FX send on the back of the chassis as that is typically a "set and forget" knob for me.  Having said that, I've put that on the front panel on several amps also.

Once I know what you want, I'll draw a layout to match the schematic.   Since I experiment quite a bit, I have found the paralleled turret board approach useful to me in making radical changes.  In comparison,  something like a Fender style board or the Hoffman style board (which is great) is much more difficult for me to add mods or make significant changes.

IF you know exactly what you want and there will be NO mods or changes, then any of the style boards are great, IMO. 

[purpletele]

OK, since you never provided a schematic for me that matches your amp,  ........... I've made a guess.  I've change my schematic to match as closely as possible what Geezer's had with a few minor changes.

Once you've confirmed your (not Geezer's) schematic, then I'll edit the layout to match what you have with the mosfet CF and FX added.

Do you use Geezer's relay switching or put that switching on a toggle switch?

Would you like to have a toggle switched mid-boost added?

I definitely would stay with a 270-0-270 transformer (or a 275-0-275) that has at least 125ma & use a 5Y3GT (old stock) rectifier. 

Do you have ExpressSCH on your computer?  If you have Windows and don't have ExpressSCh, please consider downloading this free program. 
https://www.expresspcb.com/expresssch/

With respect, Tubenit

Jeff,

I have attached the schematic and layout that I used for Billy

I am working on the board drawings as we speak.  I have it at about 14" long, the chassis is 17 1/2".

I will review the options that you provided.

a. I think the Mid Boost toggle might be cool.

b. On the schematic that I used I installed the boost with a toggle switch, I did not use relay.  Not sure if its right

Sun is coming up, time to sleep for a bit.

[tubenit]

Great!  Sounds like you've got a reasonable plan and have set it in motion. 

Please keep us posted and let us know how it's going and turns out.

with respect, Tubenit

[purpletele]

Great!  Sounds like you've got a reasonable plan and have set it in motion. 

Please keep us posted and let us know how it's going and turns out.

with respect, Tubenit

Mr. Tubenit,

I have enclosed a pdf of my board 14 in x 3.5 in.  Depending on what you have up your sleeve I think I can get everything on this board, or I can use the board stretcher option and add an inch.

I also think I can scooch things to the left and gain at least an inch on the board as well.

I have started the power section as you can see.  I do not have a problem adding controls for the FX Loop, but maybe they should go in the back.

I really like the way the amp responds with the tone stack that I have built and I really like the gain function, in fact I think it is the predominant feature.

I think you nailed the description of this amp, and I understand and feel what you described as I play it.  Therefore, if you can take the information from the board size and its potential adjustments and then help design a pre amp section based upon your recommendations that would be super duper.

BV

[tubenit]

You've never answered my questions of 1) do you have ExpressSCH downloaded on your computer and 2)  do you want the HoSo56 minimalist with FX or  "option 2"?

So, I didn't know which one to draw up for you?  So, I drew up option 2.  IF you want the minimalist approach, you can edit it yourself easily with ExpressSCH.

You will definitely want the FX level pot on the front of the chassis. It's like a pre-LTPI master volume.  The FX send pot can easily be installed on the back of the chassis as it is more a "set and forget".

CHECK for ERRORS!   Any discrepency,  go with the schematic.

with respect, Tubenit

[purpletele]

You've never answered my questions of 1) do you have ExpressSCH downloaded on your computer and 2)  do you want the HoSo56 minimalist with FX or  "option 2"?

So, I didn't know which one to draw up for you?  So, I drew up option 2.  IF you want the minimalist approach, you can edit it yourself easily with ExpressSCH.

You will definitely want the FX level pot on the front of the chassis. It's like a pre-LTPI master volume.  The FX send pot can easily be installed on the back of the chassis as it is more a "set and forget".

CHECK for ERRORS!   Any discrepency,  go with the schematic.

with respect, Tubenit

Jeff,

I do have ExpressSCH on my laptop.  I can edit if necessary.

I like what you did quite well, no need to edit any further.

Thank you, I will start loading that up in Visio. 

BV

[purpletele]

I had the fun opportunity to have three local gunslingers play through the HoSo 56 Science Project.

The unanimous result was that the amp needs more Bass and Mid control, the top end is covered and a little trebly but adjustable.

I have a .02 OD cap for the Mid and Bass.  The pots are installed with values as designed.

What steps to I take to achieve more Mid and Bass response?

[tubenit]

You can try .02 caps post LTPI. You can try a different speaker. You can use Duncan Tone Stack calculator.

[purpletele]

You can try .02 caps post LTPI. You can try a different speaker. You can use Duncan Tone Stack calculator.

Thanks, I haven't tried the tone stack calculator.  I'll start there.

[sluckey]

Things I would try one at a time...

Put a jumper across that 470K||.01µF between the CF and tone stack.
Tack a 22µF across the cathode bypass cap for V1.
Tack a 50 or 100µF across the cathode bypass cap for the output tubes.
Increase V1 coupling cap to .047µF.
Increase the PI output coupling caps to .047µF.

If you find that one of these things moves you in the right direction then leave it in place and try another.

[John]

One easy peasy thing to try, is tack a .022 in parallel with your .01 coming off V1-A.


*edit* See Sluckey's #4.

[purpletele]

Wow!


Thanks guys, I have some good experiments to try.

[purpletele]

New Unamed HoSo 56 FX Design by Tubenit


I wanted to try designing a board that is easy to work on and see all of the connections.

Are there any drawbacks to having a big board?  All of the transformers are standup style.

[purpletele]

Things I would try one at a time...

Put a jumper across that 470K||.01µF between the CF and tone stack.
Tack a 22µF across the cathode bypass cap for V1.
Tack a 50 or 100µF across the cathode bypass cap for the output tubes.
Increase V1 coupling cap to .047µF.
Increase the PI output coupling caps to .047µF.

If you find that one of these things moves you in the right direction then leave it in place and try another.

Update:  I started studying the notes provided for the tone stack tweak.  I played the amp with the MV down low and as expected not much response in the tone stack. 

When the fireworks started this evening I cranked the MV and opened up the gain and everything is there and it is quite an impressive Voxy grind.  The tone stack works well. 

So, my colleagues and I all fell into a trap.  I left the amp in the shop for guys to try.  They had the MV down really low and didn't fully open up the throttle.

I had to wonder if I had wired something incorrectly, otherwise how could Geezer's and Tubenit's design not be voiced correctly?   

I am pleased with the design and tone of the Hoso 56 for this amp, which will continue to be an experiment.  I think the above mentioned guys have nailed the voicing, no need for tweaking any further at this point.

I can get a real good Billy Gibbons tone similar to the tone on 'Waitin on a Bus', I can also get a good Van Halen tone with an EP Booster and light delay.

I can now return to my limited focus on the Hoso 56 FX and the Luckey Deluxe.

[jojokeo]

Brian,
I know you seem happy with the bass response currently but that "traditional" Marshall tone stuck and values is notoriously weak in low end response. For a puposeful reason when used in a Marshall circuit. The bass cap (middle one) should/could be .1uF for most amps with "normal" increased bass response.

[purpletele]

Oh,

Ok I'll check that out. 

Thanks Joe

[purpletele]

Brian,
I know you seem happy with the bass response currently but that "traditional" Marshall tone stuck and values is notoriously weak in low end response. For a puposeful reason when used in a Marshall circuit. The bass cap (middle one) should/could be .1uF for most amps with "normal" increased bass response.

Just a follow up:

I tried a .1 cap to test the outside limits and indeed the bass started getting sloppy

I used a ,01  in lieu of the .022 for the Bass Cap,  that worked quite well.  Much better response.

Cool amp.

[purpletele]

HoSo 56 FX Re-Build

Here is a progress shot of the HoSo 56 FX.

[purpletele]

HoSo 56 Re-Build


I finally put together the HoSo 56 where I reconfigured the board to have everything up top on the board.

I have been piecing it together rather slowly, but made a push to get it going.

The amp started right up and seems to be working fine, or at least idling fine, real quiet.

It's late and I don't want to blast to see how it sounds with any volume, but its playing well.  The MV seems to be working fine.

Solid Filament voltages of 6.5 range.

If nothing else it is quite pleasing to re-draw this circuit using Visio, design a turret board, have Doug build the board within hours of sending it in, etc,, and then to have it come together and start up.   That provides a quiet sense of accomplishment. 

None of my colleagues have a clue of what goes into these amps.