The NSV6B Musical Instrument Amplifier kit takes 'boutique' to the next level

(under construction)


Imagine an instrument amp kit that allows you build flexibility, easy assembly, and, when it’s all done n’ dusted, terrific tonal variations. It’s here, ready for you!

The CLASS IX NSV6B is a tube design based on the Traynor YBA2 1970’s vintage bass amp. This is the highly prized 6V6 version circuit. But it’s more than a bass amp. With a built-in tube overdrive preamp section you’ll be able to get those creamy bluesy tones you’ve been after. This amp does clean really well too. It loves pedals. The sound is somewhat ‘Marshallesque’,and a bit ‘Fenderish’ depending on the input you plug into. Amazing tone that actually sounds a tad better than the original amp this is modeled after. I won’t get into the why’s or technical stuff, largely because I’m not giving away why this amp sounds as good as it does. You’ll have plenty of opportunity to research once you’ve started in on your build and you’ll discover the ‘secrets’, or maybe not.

The kit is not supplied with tubes or with transformers, and here's why. I’d have to bring them in, mark up the parts based on parts cost and shipping costs, and then charge you more shipping on top of that. And it doesn’t matter whose manufacture I choose for tubes, you’re probably going to opt for something other than what I think is good. It’s just the way instrument amps and musicians go. So, all that out of the way, here’s a platform to build a super quality ‘boutique’ amp at a fraction of the cost of a ready made unit.

OK, so it looks like you’re going to have to chase down the transformers. But before you do let me give this to you…. I’ve assembled a large number of prototypes, all with different output transformers, and none of the guys that bought the protos have any complaints. Power output has ranged from 10W to 20W RMS into 8 ohms depending on the transformers. Anything from a Hammond 1609 to  Fisher 400 stereo output tranny and all sorts of stuff in between. So what I’m telling you is that while the original design used a 5K primary, I’ve used everything from a 4K to a 10K primary with great results without modifying one bit of the circuit! Do you have any push-pull trannys kicking around? I’ll bet a lot of you do.

The instructions recommend the HAMMOND MANUFACTURING 272DX power transformer and the HAMMOND MANUFACTURING 1750S output transformer to stay true to the original circuit. You might want to use Mercury Magnetics trannys, you might get in touch with Matt at and ask him what he’s got.

The kit is supplied in modules. Module 1 deals with chassis assembly. Module 2 is the INPUT STRIP circuitry. Module 3 is the CONTROL STRIP. Module 4 is the MAIN AMPLIFIER AND POWER SUPPLY PCB. Module 5 is final assembly and testing.  All parts and detailed instructions to complete these modules are supplied in their respective poly bags. And you won’t have to learn ‘Chinglish’ to understand the instructions.  Everything is explained in proper English and illustrated where required. 


I love when my customers enjoy their experience with my products enough that they are inclined to put together videos. These two videos will show you some of the finer points that I write about. Enjoy!

VIDEO #1 - construction of the NSV6B -

VIDEO #2 - Hear the assembled NSV6B through a 212 Greenback cab -

AUDIO CLIP #1 - Freddy G of Freddy's Frets ( ) put this together -

VIDEO #3 - Matt at Musical Power Supplies in St Louis, MO ( ) builds transformers. Hear his in this circuit - 




The precision CNC routed aluminum chassis measures 16" wide, 9" deep, 2 1/2" high. Premium mounting hardware is included in the kit. All holes and slots allow the components to seat accurately with no fuss.

If you prefer, I can reverse bend the chassis to provide you with a combo style chassis. Of course some of the assembly steps will be reversed, but I've done it for a couple of amps already and it's worked out very nicely.

The 1/16" thick aluminum front panel is CNC precision routed, then sand blasted, and then powder coated Sandtex Black for high wearability. This is a very labor intensive production step. The graphics are laser engraved, not silk screened. This means your lettering is going to last for a long, long time. No short-cuts here, just high quality thinking applied to engineering a product that drips with common sense and excellence! After all, you're going to treasure this amp for quite some time and I'm sure you don't want it to rust or have the graphics rub off. Your grand kids will appreciate it!


Simple construction. This module will take you about 15 minutes to assemble. It includes PCB mount 1/4" jacks, overdrive control pot, low noise metal film resistors, and all the wiring you'll need to successfully assemble this module. The 2 sided foil printed circuit boards employed throughout this amplifier kit will ensure solid connections that will give you many years of trouble free operation. Every bit as solid as point-to-point and with the shortest possible signal lines for low hum pick-up.





The control module once again uses high quality components. Now, if you want to substitute AB or Alpha pots go right ahead. The beauty of the design of this amp is that it allows you to modify or replace certain sections of the circuitry without affecting the overall build configuration. 


Instructions are simple and complete. All the parts are in the bag so you don't have to chase anything down. Handy, huh?

Yep, those yellow guys are tubular MKT tone caps used as coupling caps. I spent a few more pesetas up front so you don't have to later. In fact, the parts used in this amp are all top quality. Not military grade, but good solid parts nonetheless. The amp lends itself to modification, so if you want to use AB carbon comps or if you want to put in Alpha or AB pots, go nuts. I've left all kinds of room inside the chassis to allow you to do what YOU want to do and not what I think you should do. You'll thank me for it later.

Now, here’s where it gets interesting. No doubt, a lot of you have tried your hand at  building an amp and before it was done you found yourself hacking away at the chassis for one reason or another only to be left with a less than excellent presentation. I kinda figured that many of you might be prone to swapping transformers, and rather than having your project looking like something out of the St Valentine’s Day massacre, I designed the chassis with this in mind. The kit comes with 2 plates to mount transformers. One is a blank plate that you cut or punch or drill, or whatever, to suit your choice in trannys. The second plate is pre-punched for use with the recommended transformers. If you screw up, or if you want to swap out transformers and want a finished look to your kit, just drop me a line and I’ll be able to supply you with new plates, or you can make ‘em up yourself. And here’s another bonus…. these plates help greatly in strengthening the chassis!

The electronic parts you’ll receive are top shelf metal film resistors, MKT tone caps, double sided 1/16” printed circuit boards, and quality wire. If you want to sub other parts, go ahead, that’s your business and I won’t tell you what you should or shouldn’t do. And, no doubt, someone will come up with a ‘super mod’ that will take this kit way over the top. So go ahead, play with it, enjoy experimenting and modding, just be sure that whatever you do, do it safely. This thing will pack a 400VDC punch and if that doesn’t kill you, it’ll sure as hell wake you up in a hurry.



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