NAD: 5F2A Princeton in a Vibrochamp XD

[JakeFuzz]

Well I picked up this amp busted for $50. I ripped all of the guts out and put in a tagboard version of the Fender 5F2A tweed Princeton circuit. All the parts are from Weber and it runs a hybrid rectifier (Si diodes make a fake center tap) with a Weber 5Y3GT copper cap. I also cut the baffle to make room for a new Jensen Mod 10" speaker. The amp also has a super cheap built in 30W 4Ohm  L-pad attenuator from parts express. I decided since I have two tube pre-amps, might as well make it so I can switch out the Fender preamp and go straight into the power tube with the Marsha and the Vox pre's. I also added a NFB variable resistor control and a bright control to switch in different tonestack capacitor values. I really couldn't figure out which mods to add since the circuit is so simple and the XD has so many front panel controls to fill. I sawed out the original EMI suppression cap and kept that in as well as the IEC connector, the fuse and the mains switch. Sounds exactly like a 5F2 should. Super loud and bubbly Fender cleans when the attenuator is down and smooth, dark overdrive when the thing is cranked. The pre-amp input works well too, I tested it with the Marshall pre and it sounds like a cranked Marshall. I am very happy with this build and would definitely recoomend the conversion to anyone. This took me about a day to wire up and cost around $120 when it was all said and done.

[GrindCustoms]

That's awesome man! Love those rescue builts that turns out as something great.

Little question about the L-Pad, even if cheap, does it get the job correctly done? I was looking to put one of those in my modded Vjr.........if it's good for what it is, i may go that route.

Rej

[JakeFuzz]

That's awesome man! Love those rescue builts that turns out as something great.

Little question about the L-Pad, even if cheap, does it get the job correctly done? I was looking to put one of those in my modded Vjr.........if it's good for what it is, i may go that route.

Rej

Yeah me too. This is also a great little alternative to my monster twin reverb. I've always wanted a 5 watt little amp. The Deacy is next! 

The L-pad works great. It has a very grainy feel to the rotation, not precise like a normal pot but the taper is perfect. The sound isn't very nice (dull and muddy) with the output almost completely attenuated but I think you could switch in a cap or two to liven it up if you played it like that all the time. I think this one was $7 at parts express and they have a huge selection of them. Works great from what I can see. More in a few weeks when I run this thing through the paces.

[GrindCustoms]

Thanks Jake!

Going to give it a try, 5watt amp are really nice.........but they still are loud as hell for my appartement rocking....

[Om_Audio]

Very cool.
C

[timbo_93631]

I think you must wake up and think, "What can I make that is gonna be totally awesome today?" 



On a serious note Paul, you are getting perilously close to pooping perfection nowadays, nice project.

[midwayfair]

This is awesome. I especially like the switch in the "voice" spot.

What's this thing weigh with the hybrid transformer in? Like 8lb?

[JakeFuzz]

I think you must wake up and think, "What can I make that is gonna be totally awesome today?"  

Haha, Thanks Tim. You should see what I get to make at work everyday. I've got a Haberdasherized Kingslayer on the table right now that's going to be pretty awesome too!

This is awesome. I especially like the switch in the "voice" spot.

What's this thing weigh with the hybrid transformer in? Like 8lb?

Yeah I may do a relabel of the knobs in the future but I am happy about how some of them lined up. There is a pink LED in the FX select spot that looks pretty cool too.

The transformer is full sized. The rectifier is hybrid. I was going to go non-bridge but I realized there was no center tap on the HV before I bought the copper cap. It still weighs about 10lb's though. Nice and light; I mean just look at all that empty space in the chassis... how heavy could it be? 

[Bret608]

Oh man, I love the Tweed sound so am excited to see this...how does this thing take to pedals?

I am steadily building up my skills to where I will be able to tackle modding my amp. That's the hope, anyway! 

[pryde]

Wow nice work indeed 

I agree about the L-pad attenuators. I run one with my 5E3 and it is perfect for low volume tweedy-raunch. I do notice that pedals don't seam to work well with the amp attenuated though. However, it takes pedals great otherwise.

[JakeFuzz]

Oh man, I love the Tweed sound so am excited to see this...how does this thing take to pedals?

I am steadily building up my skills to where I will be able to tackle modding my amp. That's the hope, anyway!  

I haven't been able to run any pedals into the front end yet. I suspect it should be pretty good though. I think with a good amount of headroom (high plate voltage on V1) and a good sized coupling cap between the first and second triode stages it will take them well. Things like the Vox get weird when you try and pump too much bass into the front end. I will test it with a variety of booster and fuzzes when I get home! I can't wait!