New 2204 clone… nearly finished

[LyseFar]

Some shots from a 2204 build I am finishing up. Initially I wanted to use a PCB but ended up with a turret board.
It is close to stock values component-wise. Bought trafos from Modulus (normal grade laminations) as I couldn’t find any on the used market within a decent pricerange.
I am using Allen Bradley resistors …as an experiment… nearly all over …… so I expect an elevated noise floor. Are in the proces of testing safety ground, component misses, cold solder joins etc. before I power it up.
When I know grounding is ok I will probably tighten up the cables ….
Sound clips will follow if the thing doesen’t explode

 

[Central Scrutinizer]

Nice work.
Looking forward to a report.

 

[anitoli]

Nice work. Cant wait to hear the clips

 

[Leonard Neemoil]

Good job.

Looking forward to hearing it.

 

[LyseFar]

Made the first startup with it yesterday. A new set of Tung Sol EL34B’s
Had it burn in for a couple of hours. BIAS rock steady. Have 442 volts on the plates.
Here is a short clip recorded on iPhone just to hear it. More will follow when I get a chance to mic it.
(Les Paul Studio 94’, Mesa Boogie Thiele Road Ready with Black Shadow C90)



Nice JMP sounding in my humble opinion. Good bottom end. Not noisy at all.

And some more photos:




Closeup of filament fusing.


And a shot with its “half” siblings in the background.

 

[anitoli]

Sounds awesome. Again nice job.

 

[LyseFar]

Sounds awesome. Again nice job.

Thank you!

 

[Central Scrutinizer]

Sounds killer!

 

[LyseFar]

Sounds killer!

Thank you! Looking forward to trying it out with the band..

 

[neikeel]

Good job!

 

[BlueX]

Looks good and, more important, sounds good! Nice build.

 

[Marcomel79]

Beautiful man, sounds killer!! Congratulation on a very nice and succesful build! Nothing more satisfying than hitting that first chord and listening to the sweet sound of your work

 

[PentodeLicious]

Sounds great!
Also nice collection you got there

 

[LyseFar]

Sounds great!
Also nice collection you got there

Thank you!

 

[LyseFar]

Beautiful man, sounds killer!! Congratulation on a very nice and succesful build! Nothing more satisfying than hitting that first chord and listening to the sweet sound of your work

Thanks! Yeah quite happy how it turned out.

 

[william vogel]

Thanks! Yeah quite happy how it turned out.

One thing to note about using the carbon composition resistors. I’m guessing that the amp isn’t emitting an unusual amount of noise, at least I hope so. If it did, don’t immediately blame the resistor choice. The most noise I find in amplifiers is from ground loops or magnetic coupling and sometimes a parasitic oscillation. I’ve built many amps with a different array of resistors and found only until you get down to splitting hairs about the noise does the composition of the resistor come into effect. That being said, a single defective resistor (reading correct resistance outside of the circuit) can and will cause noise issues. Many times the whole lot of resistors within the amp will be swapped out at one time and the noise will disappear. Unknowingly the builder or tech will blame the components in whole for the issue and not recognize a single component defect as the problem. Yes by testing and quantified data the carbon composition resistors are noisier than other types but they also had something about them that led you to use them in the first place. Don’t condemn them wholly if a noise issue manifests upon startup, look for sources built into the amp from circuitry or placement.

 

[LyseFar]

One thing to note about using the carbon composition resistors. I’m guessing that the amp isn’t emitting an unusual amount of noise, at least I hope so. If it did, don’t immediately blame the resistor choice. The most noise I find in amplifiers is from ground loops or magnetic coupling and sometimes a parasitic oscillation. I’ve built many amps with a different array of resistors and found only until you get down to splitting hairs about the noise does the composition of the resistor come into effect. That being said, a single defective resistor (reading correct resistance outside of the circuit) can and will cause noise issues. Many times the whole lot of resistors within the amp will be swapped out at one time and the noise will disappear. Unknowingly the builder or tech will blame the components in whole for the issue and not recognize a single component defect as the problem. Yes by testing and quantified data the carbon composition resistors are noisier than other types but they also had something about them that led you to use them in the first place. Don’t condemn them wholly if a noise issue manifests upon startup, look for sources built into the amp from circuitry or placement.

The amp sounds really good and it is not noisy at all. It is tight, varm and fat sounding … many levels of nice overtones. I am actually a bit surprised how lucky I was with this one. I had prepared myself for noise as it it the first time I used the carbon composition reistors. Now I plan to do a model 1987 with these resistors as well. We will see.

 

[Tatzmann]

Nice. May i ask where'd you got the metal face/backplates? DIY?

 

[Matthews Guitars]

Nice work. You could probably get away with shortening some wires, particularly up front in the tone/volume control areas. I'm a big believer that excess wire = "antenna".

 

[LyseFar]

Nice work. You could probably get away with shortening some wires, particularly up front in the tone/volume control areas. I'm a big believer that excess wire = "antenna".

Thank you. Yeah there are surely a few places were I can tidy things up a bit. That said it is very quiet already.