SIII build from scratch

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AussieTim
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SIII build from scratch

Post by AussieTim »

Hi Guys Ive made my turret board but I made a basic mistake. I mucked around and got the image to print the right size for the material (G10 fiberglass 3mm thick) which was 300mm square. Once I manipulated the image to 300x75 mm I stuck it onto the board and drilled it out. The problem is that I made the board too wide and the four resisters that go all the way across the board. I could just use two smaller value resistors in series or extend the legs or add extra turrets or I could slice one side off the turret board and re-drill the holes closer in. Any suggestions of which way would be the best solution.
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JMPGuitars
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Re: SIII build from scratch

Post by JMPGuitars »

Just drill new holes for the specific stuff that's too short. You can use a regular drill bit to drill out the incorrect turrets from the backside of the board to keep it all clean.
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Re: SIII build from scratch

Post by Daviedawg »

I agree with Josh. I bought a board once with that issue. I made the mistake of trying to make it work. It was much less work to sort it properly.

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AussieTim
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Re: SIII build from scratch

Post by AussieTim »

Thanks Guys I have decided to Just put some additional Turrets in
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AussieTim
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Re: SIII build from scratch

Post by AussieTim »

Hi Guys
Another question that's probably been asked a million times before. How much space should be between tubes Im building the Trinity SIII V6 version in a combo which has 3X 12ax7,s 2X EL 84,s 2X 6v6 and an EZ81
The other things to fit is power lead, fuse, speaker plug and impedance switch. I have about 460mm to squeeze it into about 18.25 inches
It is going to be tight with about 16mm between the smaller tubes and about 25 between the 6v6,s. so I,m wondering if I should put the speaker jacks and or the power cable on the inside face instead or should I just put them all on the face Ive got and hope for the best?
Here is how solved my turret board problem
20190929_163125.jpg
20190929_163112.jpg
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crgfrench
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Re: SIII build from scratch

Post by crgfrench »

you could save a little space by using 1N5408s instead of the EZ81.
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JMPGuitars
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Re: SIII build from scratch

Post by JMPGuitars »

AussieTim wrote:
Sun 09/29/19 2:11 am
It is going to be tight with about 16mm between the smaller tubes and about 25 between the 6v6,s. so I,m wondering if I should put the speaker jacks and or the power cable on the inside face instead or should I just put them all on the face Ive got and hope for the best?
I highly recommend using an IEC socket. I'm not a fan of bad cords needing to be replaced the hard way, or for things getting knocked over instead of pulled out.

I drew 4 options for you to scale (grey box is 18.25" x 2.5"):
Tiim's-Build.jpg

You can use a combo IEC outlet, or a separate IEC + fuse, and either will fit fine. Since it's a combo, you really don't need a rotary switch. You can run the 16 ohm and the negative lead from the OT directly to the jack (16 ohm speakers are best, but obviously you can use a different one if that's what matches the speaker), and tie off the other 2 OT leads, and heat shrink tube their ends. That gives you much more room to space everything out.

Either way, you need to be extra careful with your heater wiring. Keep it nice and tight and tidy.

Thanks,
Josh
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AussieTim
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Re: SIII build from scratch

Post by AussieTim »

Thanks Josh
I was going to use an IEC socket but was concerned about the space so I thought a cord may shave a few mm off the available space. I had the same thoughts about the output socket
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Re: SIII build from scratch

Post by AussieTim »

By the way I like your layout, it looks neat what did you do the drawings with?
Although I know it is possible to fit all the tubes in the space I have I still am curious to what the optimum spacing should be and how important it is.
Please ignore my daggy looking soldering, I suppose I can claim genuine and authentic 60s style with my less than perfect drilling and soldering.
Tim
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Re: SIII build from scratch

Post by AussieTim »

Now Craig has mentioned using 1N5408s rather than a valve rectifier, I have seen circuits with switching between solid state and valve rectification claiming tighter bass and less sag etc. What is the reality here? does anyone notice much in the way of actual sound? I amps with solid state and others with tubes they all have their own sound and place but I have never directly heard switching between them so I don,t know if this is a real advantage or just salesman speak
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Re: SIII build from scratch

Post by JMPGuitars »

AussieTim wrote:
Sun 09/29/19 8:17 pm
By the way I like your layout, it looks neat what did you do the drawings with?
Although I know it is possible to fit all the tubes in the space I have I still am curious to what the optimum spacing should be and how important it is.
I did the drawings with Visio. I drew all the components from scratch for my layout designs.

Optimum spacing I don't know. I know that airflow / venting is very important if you're using a lot of tubes in close space. But garbage amps like the Triple Rectifier use a ton of tubes in a tight space, and they generally get away with it. They also use a PCB though, so that makes the heater wiring less of a concern if the tubes are board mounted.

AussieTim wrote:
Sun 09/29/19 9:14 pm
Now Craig has mentioned using 1N5408s rather than a valve rectifier, I have seen circuits with switching between solid state and valve rectification claiming tighter bass and less sag etc. What is the reality here? does anyone notice much in the way of actual sound? I amps with solid state and others with tubes they all have their own sound and place but I have never directly heard switching between them so I don,t know if this is a real advantage or just salesman speak
Tim

Advantage? I don't think that's the word. They're different, one isn't necessarily better than the other. It depends what you're looking for. Using a SS rectifier will usually give you higher voltages than a tube rectifier, so you'll need to drop the voltage. That's often done with a resistor, and that will introduce some level of sag. Different rectifier tubes have different levels of voltage drop, and different levels of sag. It really comes down to what tool is correct for the job, and what sound you're looking for.

If you're playing speed metal, you might want a solid state rectifier without a SAG resistor (or a very low value). If you're playing blues or rock, not having any sag will disappoint you.

The only advantages of a SS rectifier (outside of taste) is that it costs less, and is often more reliable, than a tube rectifier. But diodes can fail too, so it's really mostly the cost.

Regarding the bass, your cathode cap and other voicing caps have more of an affect on bass and bass tightness than the rectifier type IME.

Thanks,
Josh
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Re: SIII build from scratch

Post by crgfrench »

AussieTim wrote:
Sun 09/29/19 9:14 pm
What is the reality here? does anyone notice much in the way of actual sound? ...
Tim
In my Denim Deluxe I have an EZ81 and a quad of 1N4007s switchable, and I can't tell any sonic difference at all. But my hearing isn't what it used to be, after the mortars, machine guns, ferryboat engines and ice rink compressors, not to mention, uhh, rock concerts have all taken their toll on the ol' tympanum. Maybe there would be more detectable difference with a 5Y3 which is the saggiest full wave rectifier tube out there...
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Re: SIII build from scratch

Post by crgfrench »

AussieTim wrote:
Tue 08/06/19 6:52 am
My helper
That's a beauty!
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Re: SIII build from scratch

Post by colossal »

crgfrench wrote:
Mon 09/30/19 9:53 pm
In my Denim Deluxe I have an EZ81 and a quad of 1N4007s switchable, and I can't tell any sonic difference at all.
Do you notice a change in feel or immediacy or punch in the low end?
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Re: SIII build from scratch

Post by crgfrench »

colossal wrote:
Thu 10/03/19 3:34 pm
Do you notice a change in feel or immediacy or punch in the low end?
No. I don't hear any difference -- I thought I'd detect some sag with the EZ81 over the diodes -- it has more forward voltage drop than a GZ34 although less than a 5Y3 -- but tube or diodes both sound the same to me in this one.
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