FireFly amp build

Started by served, February 11, 2010, 04:36:48 AM

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served

Hello.

I hope here are people who has built FireFly amp.
Well, my question is to all of you, how will it sound?
The Words are: Bues, quacky, Fender strat, Neck pickups, Treble.

And I a little sceptic about the 12AU7 in the Power amp section. How can it compete with ECC84?

The idea is to build a nice bedroom amp, low wattage but good sounding.

head_spaz

Great little amp. Quite impressive actually. DougH did a real nice job on the design.
I built two for myself because I like it so much. They both sound terrific... nice and meaty.
I used the EC99 in the PA and rebiased with a 220 ohm resistor on the cathode. Puts out a little more power... more bass... better headroom... and less fizz. (Less filling... taste's great!) It goes from being a one trick pony to a one and an half prick tony.
I highly recommend using MusicalPowerSupply's OT5PP output transformer. I like it a lot better than the Hammond 125E.
I used John Calhoun's PCBs. They make this project a simple no brainer ... very well organized and almost dummy proof.
Deception does not exist in real life, it is only a figment of perception.

GibsonGM

Spaz, nice link for Musical Power Supplies...looks like they've got some good stuff @ good prices!  Thx.
  • SUPPORTER
MXR Dist +, TS9/808, Easyvibe, Big Muff Pi, Blues Breaker, Guv'nor.  MOSFace, MOS Boost,  BJT boosts - LPB-2, buffers, Phuncgnosis, FF, Orange Sunshine & others, Bazz Fuss, Tonemender, Little Gem, Orange Squeezer, Ruby Tuby, filters, octaves, trems...

Badside

Quote from: served on February 11, 2010, 04:36:48 AM
Hello.

I hope here are people who has built FireFly amp.
Well, my question is to all of you, how will it sound?
The Words are: Bues, quacky, Fender strat, Neck pickups, Treble.

And I a little sceptic about the 12AU7 in the Power amp section. How can it compete with ECC84?

The idea is to build a nice bedroom amp, low wattage but good sounding.

My personal opinion: it's still too loud for bedroom use (at least for someone in an appartment) and it doesn't really get the "cranked Marshall" vibe because of the triode configuration. Triode misses that "pissed-off" sound that pentodes have.
I ended up cannibalizing mine and built an 8W 6K6 powered amp instead (preamp is sort of a Fender Deluxe with cascaded channels and Marshall voicing). It's still too loud, but at least it sounds good.

But if you want to try it, I still have the loaded PCB (even the sockets are still on)

served

And again I am asking about this amp.
I am still a little bit afraid how it will sound.

What kind of would you compare it with? Fender? Laney? Vox? Marshall?
The reason is, that I don't want to build an amp that A would not like by its character.

head_spaz

#5
QuoteWhat kind of would you compare it with? Fender? Laney? Vox? Marshall?

All of the above.

Have you not heard the soundclips that made DougH, and his Firefly, world famous?
Soundclip 1 - Doug Hammond
Soundclip 2 - Doug Hammond
Deception does not exist in real life, it is only a figment of perception.

ampedup

have you been on ax84? there's lots of people there that have built this amp as well as the designer hangs out there. i built one, it's a great little amp, kind of marshally. i only like it for distortion, it's clean tone is kind of bland. it's a one trick pony but it's trick is pretty good. also surprisingly loud for less than a watt, not quit enough with real drums though.

brett

Hi
great amp.  I sold one to a collector (who had about a dozen of the best HiWatts, Marshalls, Fenders, Soldanos...) who wrote back and said that his girfriend rated it his best amp!!!!  He thought it was right up there, too.
It's like having two amps in one.  The cascode boost definately takes a nice, bad-sounding crunchy amp into that "almost out of control" region.

RE:Triode misses that "pissed-off" sound that pentodes...

But pentodes vary a lot.  Why do EL84s sound so much more "pissed off" then EL34s?  I don't know, but some clues are that they are usually biased much hotter (sometimes at 100% or more of their rated power), have low rated disippation, and work with smaller OTs.  The 12AU7/Firefly has some of these features.
just my 2c...
Brett Robinson
Let a hundred flowers bloom, let a hundred schools of thought contend. (Mao Zedong)

served

Well yes I have read the site, but I cant step in to dialogue there. But Anyway the train is moving and the parts are ordered. I hope this is as good as they say!
Thanks for your comments!

kulardenu

Does anyone still make a PCB for this amp?  I have a Musical Power Supply's OT5PP output transformer as my first part for this project and am looking to finally make an attempt at this amp.  Also any preferences to what version works best?  I have made a few pedal kits but this will be my first Amp attempt.  I figure you have to start somewhere and I have always liked some of the clips of the Firefly.  Any help would be greatly appreciated!

ampedup

ask on ax84.com that's where the amp started. or you could make it on an eyelet boad like i did. its alot easier to mod that way.  its a great little amp.

served

Hi.

So now, after a long time. I actually finished this a while ago. It took me about 1 month. Its really good sounding amp. I like it!
I inserter Tone control after the first stage. One pot and two caps. Easy really. It really did sound awesome!

I have a picture also.


DougH

"I can explain it to you, but I can't understand it for you."