Firefly layout if interested

[selloutrr]

the parts arrived Last night. I got the speakers installed on the baffle and tested the grill cloth it'll be perfect once I stretch and staple it on tomorrow. The speakers look great mounted in the rear of the baffle too. I added the ground switch a SPDT ON - OFF - ON carling. The ON tab runs to a Hot / Nuetral leg and the ground runs to a .047/630volt cap before being grounded to the chassis, I used a spade lug and transformer bolt. Just for excess I added an MOV. In hide sight I may have to remove it as I see it bridging the ground and cancelling out the leg switchable grounding. I'm still not happy with the faceplate / tolex covering I think i'll have a cabinet company cut it for me and clone and front and back. one more trip to the harware store and it'll be up and running! I cut the pilot light hole one size to big and it falls in so i need to get a washer to hold it in place.

[selloutrr]

It's been a Project the speaker cabinet is complete i went to the local street fair and had a name badge made for the speaker jack that turned out really great for only $5. The cabinet is loaded with a pair Jensen MOD 4 ohm 20 Watt 8" speaker's to total an 8 ohm load. the cabinet was difficult to get together after it was tolexed. i think i should have given another 1/16 of an inch of play. the speakers are mounted on the inside of the baffle and the baffle is painted white and covering in tolex then trimmed 1/2" around the edges and grill cloth stretched over. i added the tolex so if the light hits it it would have depth, and i had about 10 extra feet of it laying around.

[selloutrr]

The speaker cabinet sounds very modern. with the mid cut and low and hi boost i'm sure if i was in a alt rock band the 12" Jensen MOD would be the pudding!

I tried the speaker cab with the Epiphone Valve Jr. I was very impressed with how it brought both the cab and the amp to life. it seemed to be a great match for both pieces!

I just got the amp up and running i had some trouble with the first power transformer i guess i got a bad one cause even though i wired it as stated on the box it burned the fuse and only put out 2.3V on the heater and nothing on the 190 legs after burning the soldering lug for a split second. I got a replacement and wired it up the same way and after replacing the fuse it fired right up!!! I ran a few tests and checked components for damage it was all ok so what ever it's deal was it all inside the transformer, thankfully.

The Amp has an interesting sound I'll record some clips after I select the best tubes for it. It's very narly when pushed to the extremes but cool in it's own right! and smooth and toneful when relaxing the volume and running about 60% it's tone depends so much on tubes being pushed it's hard to judge it until i can find time to voice it. right now i just stuck a couple JJ/ telsa 12ax7 and an RCA ***** 12au7 in for the output. I think i'll start with the output first and see if i can calm some of the narl to a smoother taper i think the tube might be old. the amp is dead silent!!!! no funny pops clicks of goblins!!! I added a line out so it could be hooked to a dummy load and used as a distortion box, this should be awesome for both studio line out and when the amp is out grown it can be used to push the front end of something else.

I want to tweak the Mid control a bit for more extreme treble and boost it's still a bit conservitive for my taste, i want to know it's being turned.
I still need to mount the amp in the head cab and get the face plates made. But the hard part is over i'll try to get it wrapped up this week it's been an adventure. all said and done it's only been a 23hr build i've just been stretched in every direction so finding time hasn't been easy.
Thanks for looking It's been the motivation i needed to find the time to complete the project hopefully the next post will be the completed one for all to see!

[Structo]

Sweet little project.

pink?

How loud does it get?

How would it sound with a 12ax7 for the output?

[selloutrr]

I went with pink and white to match my daughter's guitar. She's 2.5yrs old, what can I say she likes pink.

It's not super loud but far from quiet if you where to mic it then it would be a sound guys dream cause it's not over powering but the player can still dial in the sweet spot. ( but it is it's own animal !!! ) best way to discribe it would be a nice tube pedal direct to a console, with that extra something so you know it's an amp, but you still hear the pedal. if that makes any sense. a very believable pedal

The 12AX7 is a bit to much output it works but get's a bit sizzly and wild for my taste but does seem pretty interesting as a distortion pedal / driver.

I voiced the amp and tried 12AX7 AT7 and AU7's for the output. I ended up going with a Bugleboy 12AU7 with matching sides and about 93% life left in it. smooth and clear when not pushed still musical when driven

I went with a JJ/Tesla 12AX7 in the second possition

and a Brimar ECC83 / 12AX7 / 7025 in the First postion

It's got a really hot drive / boost and can be balanced in for a pretty tasty Blues tone. Almost makes me want to add an FX loops and build a Tube Reverb for it with an old Ampeg spring pan. It sings a very pleasing mellow tone with an ES-335 and a screaming lead with a stat or Paul. With the boost full up the power chording felt a bit harsh for my ears but with a tube eq you could easily make it a studio piece. I still can't say i like the tone control i added it's not as responsive as i wish it to be. It works but it's kinda like... um is that it? if you blink you missed it. So i'll rework it a bit and i'm sure i'll get it to be as awesome as a little pink amp should be.

I'm currently rebuilding the front and back panels of the head cabinet.
I'm going back to the first design now that i figured out how to work tolex.

[selloutrr]

duplicate

[Structo]

Thanks, I was pullin your chain about the color.

I figured you had a little girl with a Hello Kitty guitar.

I hope she digs it.

[selloutrr]

it's a stratocaster knock off with a single coil P/U it's actually pretty sweet but really heavy for being a 1/2 size guitar but it holds tune. So she has the PINK (guitar, strap and picks, seemed fitting to make an amp and cab to round it out) Mostly it was the excuse i needed so the wife would let me build the amp!!!

[selloutrr]

I know I was projecting to complete the amp over the weekend but I got super anal and rebuilt the face trim. Messing it up 6 times before taking a CAD drawing to a local cabinet maker and having 2 made. I just got them this morning and they are perfect! I still need to tolex and grill the vents. I'm off for the first half of next week, ill knock them out then.

Tonight I'm Very excited to finally complete the face plate! It has been a work in progress and quite a few attempts ending in starting over. It's made of a 1/4" thick 11" wide x 3" tall lexan clear plexi. I used a CNC metal work program to layout the face plate then printed the test proof on clear sticky transfer paper and stuck it to the top of the lexan. I pealed the back film and painted the surface primer white.
If I had been able to print a mirror image of the text about 6 hours ago I would have put the sticker and the paint on the same side it looked really good while I was experimenting. but with one side painted and one side a sticker it almost has a marble effect. The best part is it's straight and works!!! I can now trace the depth and make the final chassis mounting holes in the head cabinet!!!
While I was drinking cheap beer a couple nights ago I got to thinking... The amp is for a 2.5yr old. The likely hood of the amp's speaker cable being unplugged while it's on or playing is a real possiblilty. Luckily I used a cliff jack so it had switching lugs.... I added an 8ohm 10watt power resister on the lifted side so it's got a load on the OT without a speaker and lifted when a speaker cable is inserted. The dummy load is also useful if the head is used as a distortion pedal or driver.

Here is the final To Do List:
1.) Drill out the Pilot light hole in the faceplate to 11/16" or M18
2.) Tolex the new head cabinet face front and back
3.) Add grill cloth to the Cabinet face and back
4.) Mount the chassis in the Head
5.) Mount New Panels
6.) Record Audio Samples!!!
7.) Draw up schematics / Diagrams for the MODs and post them (all easy)

should be an afternoon at most.

[selloutrr]

OK TODAY IS THE DAY IT IS FINISHED AND ROCKS!!!


Thank you to everyone who has chimed in and viewed this post. Thank you Joebob for making the post and letting me run with it. You did an amazing job on the layout!

I'm about to go record the sound samples I'll post them late tonight. here are the finished pics and the schematics for the modifications to make it a distortion pedal / preamp line driver.

[joebob]

You did a first rate job, congrats and well done, and thanks.

[selloutrr]

all worth it!!!!

[rawnster]

Dude, that's awesome!

as the mastercard commercial goes....that's priceless!

[Structo]

You are a cool dad!

She looks so cute playing that. I'll bet she loves it and you for making it for her.

[xtian]

Great build and documentation--thank you! I sprung for a Hammond 269ex PT, and will build this Firefly design. My chassis has an 8-pin socket for tube rectifier 5u4gb. I'd like to use this instead of the diode rectifier. What are the ramifications of this? Will the voltage drop lower than with the diodes, and would I have to compensate for this?

Or is using the tube rectifier silly because the Firefly will never draw enough current to realize rectifier tube sag?