5879 amp favorites?

[mountainhick]

There's been many builds here using 5879s. I've been perusing quite a few schematics with jschem.

I just got my hands on a conn strobotuner that I'll repurpose as guitar amp. It's tube compliment is really good, 6x4, a pair of 6AQ5, a 12AU7, a 12AT7 and a 5879. I am happy to use a 6N2P anywhere a 12AX7 would be better.

So wondering about 5879 input stage, perhaps another gain stage, 12AT7 PI etc.

I've built one dual channel amp with one channel a 5879 input into paraphase Gibson GA-40 style, though different power amp. Quite like it. Would like to do something different.

So the range of 5879 designs? I am open to other suggestions. What are your favorites using this tube and why?

Not in any way focused on this, but one idea, wondering about 5879 instead of EF86 for matchless/vox kind of thing.

[passaloutre]

Not in any way focused on this, but one idea, wondering about 5879 instead of EF86 for matchless/vox kind of thing.

I recently did an all "American tube" version of the AC15/Spitfire using an old BH Filmosound amp with 5879,12AX7,6V6,5Y3. I have some noise issues to work out in the tiny chassis, but overall it's a nice round, less-compressed tone than the "English tube" Spitfire I made prior.

[TIMBO]

This one is worth doing
5879 Blues Bassman

[kagliostro]

Gibson Les Paul GA 40

https://el34world.com/charts/Schematics/files/Gibson/Gibson_les_paul_ga_40.pdf


Sorry, I missed you want to change from the GA 40

Franco

[mountainhick]

This one is worth doing
5879 Blues Bassman

I have found another version in the Jschem forum, looks potentially desirable, and easy enough to adapt to 6AQ5s.

TIMBO, what's your take on a 12AT7 as PI in that design? Have my own thoughts, but would like to hear others' take on it.

[mountainhick]

Gibson Les Paul GA 40

https://el34world.com/charts/Schematics/files/Gibson/Gibson_les_paul_ga_40.pdf

Sorry, I miss ed you want to change from the GA 40

Franco

No worries, Yep been there, done that, and will again, but with 6SJ7s.

[SoundmasterG]

Use the 5879 as the second stage instead of the first stage. You get more of the good pentode effects without all the microphonic instability that pentodes often give. Merlin has a lot about it in his books and he's right.

Greg

[mountainhick]

Use the 5879 as the second stage instead of the first stage. You get more of the good pentode effects without all the microphonic instability that pentodes often give. Merlin has a lot about it in his books and he's right.

Greg

Any examples/schematics that use no more than three 9 pin tubes for preamp and PI?

[passaloutre]

Use the 5879 as the second stage instead of the first stage. You get more of the good pentode effects without all the microphonic instability that pentodes often give. Merlin has a lot about it in his books and he's right.

Greg

Any examples/schematics that use no more than three 9 pin tubes for preamp and PI?

This one is my new favorite: https://el34world.com/charts/Schematics/files/Kay/Kay720.pdf

That first 5879 doesn't grind very much, but it blasts the pentode that comes after it in the 7199. If you don't want to spend 7199 money, try a 6AN8 or 6GH8. In my build (https://el34world.com/Forum/index.php?topic=33360.0) I even replaced the 5879 with a MOSFET. Sounds great.

If you need to fill a third 9pin socket, you could use it for trem or one-tube reverb.

[tubenit]

Over the years, I've built all these using a 5879.  Currently, I still own two of them.   The HoSo56 with FX and the Tweed BluezMeister Lite.


I've been very happy with all of them.


With respect, Tubenit

[bmccowan]

I like that tube, and have built a few:
Matchless Clubman with 5879 instead of the ef86 and a 6V6 power amp. This amp is much tighter than a GA-40.
Modified Dr. Z Z-28 circuit. I married the Z-28 power amp, PI, and tone stack with a Clubman style preamp. No divorce yet.
Tubenit's Minimalist HoSo 56.
GA-40 preamp with a Valco 6973 power amp.

[mountainhick]

I like that tube, and have built a few:
Matchless Clubman with 5879 instead of the ef86 and a 6V6 power amp. This amp is much tighter than a GA-40.
Modified Dr. Z Z-28 circuit. I married the Z-28 power amp, PI, and tone stack with a Clubman style preamp. No divorce yet.
Tubenit's Minimalist HoSo 56.
GA-40 preamp with a Valco 6973 power amp.

Coincidentally, I just stumbled onto the Clubman as well. It looks and sounds like a good one for me. Do you still know what kind of voltages you were running with that circuit? And, did you use a parallel power supply scheme?

I am also looking at the Vox AC10 as a good starting point.

[mountainhick]

Over the years, I've built all these using a 5879.  Currently, I still own two of them.   The HoSo56 with FX and the Tweed BluezMeister Lite.


I've been very happy with all of them.


With respect, Tubenit

Simple version of Hoso sans reverb looks pretty much like same architecture as the Timbo 5879 bassman? Couple different tweaks. What's your take on your configuration in terms of sound/response?

The OD lite looks like a contender.

Dmars has too many tubes.

I'll pass on the mosfet.

[tubenit]

I think the HoSo56 has sort of a fat touch sensitive chimey tone with the right speaker.  My Minimalist HoSo56 using 6BM8 tubes is my #1 gigging amp. And it's a great home recording amp.

Before you throw out the mosfet idea, I suggest you read this:  geofex.com/Article_Folders/mosfet_folly/mosfetfolly.htm

If it's a concern about how to do the mosfet in a layout, I can help with that. If it's a tone thing ........... I don't see it an issue. 


The advantage of the mosfet is then I can move a tube triode for a psuedo kinda active FX loop recovery stage. This has worked well for me with reverb, delay, chorus or phase pedals.  I can NOT tell any difference at all between a mosfet cathode follower and a tube triode cathode follower tone wise.

I am not saying you "should build" any of these. Simply throwing out considerations I've been happy with.

With respect, Tubenit

[SoundmasterG]

Use the 5879 as the second stage instead of the first stage. You get more of the good pentode effects without all the microphonic instability that pentodes often give. Merlin has a lot about it in his books and he's right.

Greg

Any examples/schematics that use no more than three 9 pin tubes for preamp and PI?

I can't think of any commercial examples that use the pentode as the second stage. I'm sure there are some out there but not a lot probably. Back in the day they would often just use a pentode at the input like Vox did, but nowadays we know better. A lot of people have built their own things like Tubenit did. I did a parallel 12AX7 into a tone stack, volume control, and 5879, then into a LTP phase inverter on one amp. The power tubes are 7868's so they need a bunch of gain in front of them, and it sounds and most importantly feels great. It won't do a really nice clean, but it gains up like an AC30, but is a thicker sound and is maybe even more touch sensitive. It quickly became my #1 amp after I made in in 2012, and it's still going strong. I own an AC30 too. I might make another one with a separate clean channel, but there are so many other circuits I want to build so we'll see.

Greg