DIY Purifi Amp builds

[tomchr]

Shrink tube or a techflex-type covering, I assume. Or maybe even just wrapping them in electrical tape. Anybody?

Techflex looks pretty but I doubt it meets the requirements for reinforced insulation, which is what you're after. Maybe heat shrink first and then Techflex to make it look pretty. You could tie it off with zip ties (or wax cord if you know how to use that ) at the standoffs on the power supply.

I suppose you could also cover the lid with a sheet of mylar, 0.4 mm thick minimum, where the power harness touches.

Alternatively one could sacrifice an old power cord and make a new double-insulated harness.

The relevant standard is the IEC 61140 as I recall. If you search a bit you can find copies of it floating around on the 'net. It's a worthwhile read and a mandatory read for any manufacturer IMO.

Tom

 

[Billy Budapest]

Techflex looks pretty but I doubt it meets the requirements for reinforced insulation, which is what you're after. Maybe heat shrink first and then Techflex to make it look pretty. You could tie it off with zip ties (or wax cord if you know how to use that ) at the standoffs on the power supply.

I suppose you could also cover the lid with a sheet of mylar, 0.4 mm thick minimum, where the power harness touches.

Alternatively one could sacrifice an old power cord and make a new double-insulated harness.

The relevant standard is the IEC 61140 as I recall. If you search a bit you can find copies of it floating around on the 'net. It's a worthwhile read and a mandatory read for any manufacturer IMO.

Tom

What about automotive wire harness tape? It’s a felt-based electrical tape.

https://www.amazon.com/dp/B01I2MLN2Q?ref=detail_main_image_block_ivx_share

 

[Billy Budapest]

Shrink wrap is ok. Mostly this stuff is used, but you will need something to finish the ends nicely...

Audtek Black Split Braided Cable Wrap 12 ft. (parts-express.com)

That’s the Techflex-type stuff I mentioned and tomchr opined does not meet IEC spec.

 

[tomchr]

What about automotive wire harness tape? It’s a felt-based electrical tape.

... which is intended for low-voltage use. You need something with enough dielectric strength to count as "reinforced insulation". You can see the definitions in the IEC standard.

Tape would not be my first choice. It has a nasty way of becoming undone over time. If I was to use tape I would consider Kapton tape. I believe the generic term is polyamide tape. It's deep amber in colour usually and is rather expensive. And it's still tape, which can come undone.

Tom

 

[ironhorse128]

Cool. Thanks for the suggestions. I guess I will do the shrink tubes and then Techflex to make it look good thru my plexiglas frontplate

 

[Rick Sykora]

That’s the Techflex-type stuff I mentioned and tomchr opined does not meet IEC spec.

While am sure Tom knows his stuff, do not need to sacrifice the good for the perfect.

It is a hobbyist amp and does not need to meet certs.

 

[TimoJ]

Cool. Thanks for the suggestions. I guess I will do the shrink tubes and then Techflex to make it look good thru my plexiglas frontplate

Can't you just bend the wires so that they don't touch the top?

(Personal taste but I just don't find that front panel view (mostly of the Hypex PSU) very appealing... Painting inside of the plexiglass with black color could give it a pretty nice deep gloss look. Plexiglass top covers sometimes look nice, but this just doesn't do it for me.)

 

[ironhorse128]

Can't you just bend the wires so that they don't touch the top?

(Personal taste but I just don't find that front panel view (mostly of the Hypex PSU) very appealing... Painting inside of the plexiglass with black color could give it a pretty nice deep gloss look. Plexiglass top covers sometimes look nice, but this just doesn't do it for me.)

Sure it could look better. But after living with it for a few days I really enjoy it. Much nicer than the black VTV frontplate. Also there is this red glow from the eval1 which is very nice.

 

[ironhorse128]

I installed the shrink tube and the techflex. It was pretty easy and strait forward. Had some techfex leftovers from my speaker wires.

 

[ironhorse128]

I would like to connect a power button to my VTV EVAL 1 amp. I know that I have to connect the power button at J3 of the EVAL1 board between Pin 1 and 6. The problem is that there is this ribbon cable between J4 of the power supply to J3 of the EVAL1 board. It connects to pins 5 (positive rail voltage regulator input),6 (ground),7 (negative rail voltage regulator input).

I guess I cannot just remove the existing ribbon cable, right?

My question is: As somebody that is not really technical skilled in electronics, is there a safe and easy way to make this work (connect the power button to my VTV EVAL1 amp)?
I have some basic skills and tools. I could also buy adapters or tools. I would appreciate any help.

Here is J3 of the EVAL1 board.
View attachment 144340

And this is the other end of the ribbon cable at J4 of the power supply.

View attachment 144341

Any suggestions on how to integrate the power button?
I found in the SMPS1200A400 user manual that there is also a SMPS-standby mode (jumper J5.1). What is the difference between using the EVAL1 standby mode vs. the SMPS-standby mode?
Additionally, I found that I could access GND from J5.5 of the SMPS1200A400. So I could place the power switch between J3.1 of the EVAL1 and J5.5 of the SMPS. Then J5.2 of the SMPS offers amp standby which likely would not do much as the VTV did not fully connect the SMPS to the EVAL1. I am really lost.

SMPS:

EVAL1:

 

[Billy Budapest]

Can somebody who has used the neurochrome buffers and speaker protection modules in their build post a picture of the inside of their amp? I’d like to see how everything is wired up. Thanks!

 

[JimB]

Any suggestions on how to integrate the power button?
I found in the SMPS1200A400 user manual that there is also a SMPS-standby mode (jumper J5.1). What is the difference between using the EVAL1 standby mode vs. the SMPS-standby mode?
Additionally, I found that I could access GND from J5.5 of the SMPS1200A400. So I could place the power switch between J3.1 of the EVAL1 and J5.5 of the SMPS. Then J5.2 of the SMPS offers amp standby which likely would not do much as the VTV did not fully connect the SMPS to the EVAL1. I am really lost.

SMPS:

View attachment 144631

EVAL1:

I think there is no simple answer to this, unless you intercept the MAINS cable and truly turn power off (like your back panel switch does). Otherwise, you can only put the system in a Standby state. And for that, you want to put the SMPS into Standby. And that requires a pull-up voltage. And that requires an additional power supply that is always on. This has been addressed a few times in the past in this LONG topic, often in the context of using 12VDC external trigger.

 

[JaapDeventer]

I did put an extra mains switch on the front. It really powers up and down very nicely.

 

[tomchr]

It is a hobbyist amp and does not need to meet certs.

True. But it should be safe to use. Besides, didn't it start as a commercial product or kit?

Tom

 

[Rick Sykora]

True. But it should be safe to use. Besides, didn't it start as a commercial product or kit?

Tom

Yes, ever looked at a Ghent case in detail? It is target rich opp to improve. Grounds that lack knurled washers and unclear ground paths for other parts of the case. Wiring harness lengths that force compromised routing choices. Many have no case fuse (though this one may have in the EMI filter).

 

[Billy Budapest]

Grounds that lack knurled washers and unclear ground paths for other parts of the case.

Ever seen the inside of a Rega Brio case? That’s how it should be done.

 

[ironhorse128]

Ever seen the inside of a Rega Brio case? That’s how it should be done.

The general outline of the Rega Brio does not look that clean though with all these wires.

 

[mocenigo]

The general outline of the Rega Brio does not look that clean though with all these wires.
View attachment 145218

It is actually clean and well laid out. For instance, all the exit points of wires from the transformers are away from the electronics. This needs slightly longer leads to the various points, but this actually adds to the cleanliness.

 

[Billy Budapest]

The general outline of the Rega Brio does not look that clean though with all these wires.
View attachment 145218

I think you are missing my main point. To wit, look at the star ground and how it attaches to the base, rear, and sides of the amp. There is also a ground wire attached to the lid (not shown in your photo).

 

[Billy Budapest]

Here is a clearer picture of the previous iteration of the Brio. The loose wire at top is the ground connector for the lid. All the grounds connect at the star grounding point between the two capacitors. The bottom plate chassis ground also connects to an external ground lug for your turntable.