Tweeter Amp for OB or Horns

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IslandPink
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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Mon Jan 14, 2019 8:06 pm

Yes but you've not got a fixed box size :confused3: This 'neat' business is doing my head in. There's still one too many parts for this volume. I'm trying to avoid getting the input phonos too near any toroids, getting the volume control pot mounted, the shaft in ( from the side ) , making sure there's enough room for the first cap on some tag board between the mains Tx and the choke. if only there'd been a way of somehow modelling the box and all the sizes and shapes of the parts, in 3D, before I started building :!:
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

izzy wizzy
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Re: Tweeter Amp for OB or Horns

Post by izzy wizzy » Mon Jan 14, 2019 8:30 pm

IslandPink wrote:
Mon Jan 14, 2019 8:06 pm
if only there'd been a way of somehow modelling the box and all the sizes and shapes of the parts, in 3D, before I started building :!:
If not this time then next time. Sketchup. Be glad to help. I use it to model things like this among other things.

Cheers,
Stephen

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IslandPink
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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Mon Jan 14, 2019 10:02 pm

You're very kind. Maybe one day the 4P1L>300B amp or a 4P1L>GM70 amp will need a box.
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

SimonC
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Re: Tweeter Amp for OB or Horns

Post by SimonC » Tue Jan 15, 2019 8:20 am

IslandPink wrote:
Mon Jan 14, 2019 8:06 pm
.... if only there'd been a way of somehow modelling the box and all the sizes and shapes of the parts, in 3D, before I started building :!:
As Stephen says there is sketchup, and if you want something with a bit more power Autodesk's Fusion360 is well worth a look. Its free for non-commercial use and there are a lot of tutorials on youtube for it. Slightly more off topic, but I've been very impressed by the cam functionality that comes with it.

Simon C

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IslandPink
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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Wed Jan 16, 2019 8:08 pm

OK , I might have it.
Daddy Bear is in the inside, in the corner - we know that.
Mummy Bear will have to go outside, on the top, just near Black Gatey.
Baby Bear will have to go upright, attached to a bracket from the centre channel-piece.
Meanwhile the knob will come in the side, just near the rect...ifier valves.
Inputs will come into the top plate, straddling the centre-line.
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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Re: Tweeter Amp for OB or Horns

Post by RhythMick » Wed Jan 16, 2019 8:37 pm

izzy wizzy wrote:
Mon Jan 14, 2019 8:30 pm
IslandPink wrote:
Mon Jan 14, 2019 8:06 pm
if only there'd been a way of somehow modelling the box and all the sizes and shapes of the parts, in 3D, before I started building :!:
If not this time then next time. Sketchup. Be glad to help. I use it to model things like this among other things.

Cheers,
Stephen
Another alternative is Tinkercad.com which I used. SketchUp looks like it's more accurate, but that's probably just my skills lacking. Tinkercad I found very quick to get going with.

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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Sun Jan 27, 2019 8:11 pm

Thanks. I'll see how I feel about trying it for the next amp ( phono or GM70 ) . To be honest, these days I have a morbid fear of forgetting how to do something else, if I learn some new software. I'm currently stuck trying to remember things about LT Spice.

Meanwhile, progress here this weekend. Wooden surround also progressed, will post a pic when the last ops on that are finished.
I need to post a new circuit drawing - I haven't caught up with the pentode bit properly, and yesterday I realised it would be a good idea to have a drop-down filter ( LC ) for the pentode drivers - hence the late addition of a small 9H choke near the output transformers - which I'm not 100% happy about, but we'll see. Currently digging in boxes for something nice for 16k anode load and ~100k screen dropper. Didn't plan my last HiFiColl purchase around this variant !
Tweeter_progress.JPG
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Tue Jan 29, 2019 12:30 pm

Circuit re-hash :
Tweeter_Amp_Jan2019.jpg
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Tue Jan 29, 2019 1:11 pm

Balls ! The 3.9u goes to the E83F cathode, not ground !
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Sat Feb 02, 2019 11:46 pm

I find it unlikely that I only bought 1-off Mundorf 3.9u/350 EVO and 1-off 0.1u/630 ZN cap.
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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Re: Tweeter Amp for OB or Horns

Post by pre65 » Sun Feb 03, 2019 11:58 am

IslandPink wrote:
Sat Feb 02, 2019 11:46 pm
I find it unlikely that I only bought 1-off Mundorf 3.9u/350 EVO and 1-off 0.1u/630 ZN cap.
Welcome to the world of old (er) age Mark. :lol:
Life is what happens to you while you're busy making other plans. John Lennon

G-Popz THE easy listening connoisseur. (Philip)

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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Sun Feb 03, 2019 12:27 pm

They are probably in the same place where the tools go to hide.
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Sun Feb 03, 2019 3:40 pm

ps. also, for 6AX4 , now 17AX4 :roll:
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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IslandPink
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Re: Tweeter Amp for OB or Horns

Post by IslandPink » Sun Feb 03, 2019 9:56 pm

Wood surround gave me the chance to get the wood bit and brace out to do the hole for the volume control -
Tweeter_surround.JPG
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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Re: Tweeter Amp for OB or Horns

Post by Ray P » Mon Feb 04, 2019 8:40 am

IslandPink wrote:
Sun Feb 03, 2019 12:27 pm
They are probably in the same place where the tools go to hide.
Yep! Searched high and low for my fine rat tail file last weekend but to no avail so I popped down to the local Screwfix and bought a new one. Guess what was sitting on the work bench when I got back!

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