[linuxworks]

and is that a bantam in the round wood thing?

I'm expecting my metal cases this week (maybe). the build will have to wait until later, though

yours came out well! everything fit ok?

 

[linuxworks]

Quote:

Originally Posted by rds /img/forum/go_quote.gif I find it's handy to have an adjustable DC power supply around. So I made this Tread with socketed R1 and R2. With this setup I can easily get any voltage between 12V and 35V using tangents resistor table (taped to the top of the case with the extra resistors. I also added a header so I can connect wires directly if that is more convenient.

for extra credit, why not take a small cheap lcd DMM, hack it apart, and hard wire it to voltage, 50v scale (say). then cut a rectangle opening in the plastic and hot-melt the lcd behind it. then you can KNOW, always, the exact DC output.

sometimes I see small 'cheap' DMM's at dollar store prices which would suit something like this just fine. small size is key, so that it would fit inside your box; but I've seen plenty of $5 voltmeters that are very tiny and might.

 

[cetoole]

Quote:

Originally Posted by linuxworks /img/forum/go_quote.gif and is that a bantam in the round wood thing? I'm expecting my metal cases this week (maybe). the build will have to wait until later, though yours came out well! everything fit ok?

Looks like, and another under the table. I have said it before, but it bears repeating, good work Max.

 

[Fred_fred2004]

It took me so long to get it built I didn't have the heart to put it in a box, just bending the metal has given me a new respect for all you case builders

 

[linuxworks]

I had the urge to do some mini-soldering work, so I build a TinyLatch(tm)

the top part is a 'module' that has 4 pins that the user would care about: pushbutton, power, ground, output. that's it - that's my latch

yes yes, its just a D-flipflop but I needed a latch to hold a push on/push off switch for my dac/amp project.

a surface mount cd4013 is soldered to a DIP8 socket with some wire-wrap wire connecting the right pins (R,S,gnd). that's the basic module.

that module is plugged into a 'test socket' that simulates a real world circuit. it has a debounce cap (.1uF, one of the red ones), a normal chip bypass (that other red cap), a led and resistor to show the Q or ~Q state of the latch and a button for testing.

no circuit board was used - just regular old air

and so ends my edition of the Sunday Sircuit(tm).

 

[Captain ?degard]

What is that? o__0

 

[shortkidsrus]

Quote:

Originally Posted by linuxworks /img/forum/go_quote.gif its just a D-flipflop but I needed a latch to hold a push on/push off switch for my dac/amp project.

Are you going to use a transistor switch or a relay to switch the power on your dac/amp?

Edit: Just realized it wouldn't be practical for switching power. What are you going to use it to switch? Sources?

 

[linuxworks]

Quote:

Originally Posted by shortkidsrus /img/forum/go_quote.gif Are you going to use a transistor switch or a relay to switch the power on your dac/amp? Edit: Just realized it wouldn't be practical for switching power. What are you going to use it to switch? Sources?

I'm planning on a few toggle buttons for some features:

- crossfeed on/off
- mega-bass (bass boost) on/off
- mute on/off
- input select (toggle: spdif, analog)

maybe more, if I think of them.

so you can see having a toggle button with a push on/off feature will be useful. these will all trigger relays, so in the crossfeed option the relay will close the 'enable' pads on the pc board. on mute, the relay will change the gain by switching in or out an extra resistor. on bass boost, it will add a parallel R/C in series to the feedback resistor like the PPA series does.

I could have gone with mechanical switches - BUT - a goal is to have my box be IR remote controlled. each push of an IR button will be a momentary pulse (or steady on, for volume up/down) and so I did need something that would capture single button presses and keep the state. I can then just wire in parallel the front panel push buttons and the IR remote control pins and they both will have the same interface.

 

[linuxworks]

here's a shot of my 2nd build of the gamma1; this one is meant for 'permanent mounting' inside a home preamp. I didn't need the usb board for this and also wanted to off-board mount the goodies. here's an angle shot of some of the essentials:

I (re)used the gold rca jack AND the toslink receiver module from the ebay 'noodle dac' board (just unsoldered both and wired them onto my custom wires).

what I found is that some toslink modules need 5v (mine) and some need 3.3v (the gamma1 default torx module) - and so I had to 'left a leg' (lol) of my red offboard connector and shortcut that wire directly to the +5vdc line, which is what the DAC takes as its B+.

that was enough to make my 'generic' toslink module work with the AMB gamma1.

all connectors on the gamma1 are now 'hacked' with molex connectors; so this module can now just drop-in on a suitably wired preamp and if/when I want to swap in a different DAC I just have to follow the same general kind of offboard pinouts.

 

[liltehood]

If you want your amp Remote Controlled i would by a Receiver and the controller. The Receiver should be connected to an mirco prozessor (Atmel AVR f.e.) and the microcontroller could be installed in the signal pathes. the only problem is the poti. youll need a digital...

hood

 

[linuxworks]

I'm going to use motorized pots and an h-bridge. so all I need is a constant volume-up and volume-down signal.

I decided to buy one of these:

TinyIR2 Learning IR remote control receiver

I'll report back with my success (or not)

that one looks really good to me, as its 'learning' ! I could use my tivo remote's up/down volume buttons and 'hijack' them for this preamp. that scores extra extra points in usability, in my book

then I can tie some of the pin outputs to relays for mute, crossfeed and so on.

 

[Hayduke]

Quote:

Originally Posted by linuxworks /img/forum/go_quote.gif I'm going to use motorized pots and an h-bridge. so all I need is a constant volume-up and volume-down signal. I decided to buy one of these: TinyIR2 Learning IR remote control receiver I'll report back with my success (or not) that one looks really good to me, as its 'learning' ! I could use my tivo remote's up/down volume buttons and 'hijack' them for this preamp. that scores extra extra points in usability, in my book then I can tie some of the pin outputs to relays for mute, crossfeed and so on.

That thing looks cool! You're making me want to build an amp for my living room

So far I've only been thinking along the lines of home/work office and semi-transportable types. If I can make something that is remote control and can select inputs via the remote, I might have to pursue that. Of course, that project would be way way down the road. There are lots of things I want to build before that.

I'm excited to see your end result Linuxworks.

 

[linuxworks]

progress on my combo 'everything in one box' box

maybe I'll call it....

"Greater Than Zero(tm)"

left to right: gamma1 DAC from amb labs; pimeta from tangentsoft; TREAD power board also from tangetsoft. the 2 torroids are dual 12v and dual 5v (effective). one 12v rail is for the pimeta (its actually measuring at 20v, which is ample for me); one 12v rail can be used for motors; one 5v rail is used for the DAC and another can be used for the IR remote/processor (tbd). neither heatsink runs hot to the touch (finally).

gamma1 is configured (right now) for opto-in, only. I have a wire and jack for coax-in but since I have not settled on front panel jacks or IR remote yet, that is still tbd. the led for 'lock' on the DAC also needs to come to the front panel.

since the IR remote will be learning, I'll need a led for it, a hole for the receiver and a push button to 'learn'.

cable wiring is 'working ok' but not really final. I can't hear any hum at all, or noise, so the routing seems ok enough.

front panel is reused and needs to be replaced when its finalized. in fact, this 1U rackmount box used to be a pro audio thingie before I gutted it and stuck my own plastic front panel on it

its already a zero-killer (so to speak). greater than zero, in more ways than one

still a WIP, though, and more left to be done before its finally done. it is listenable and useful now, though.

 

[mattcalf]

Wow that is awesome!!
DIY All-in-one to a whole new level.

 

[linuxworks]

Quote:

Originally Posted by mattcalf /img/forum/go_quote.gif Wow that is awesome!! DIY All-in-one to a whole new level.

thanks

I was joking with cetoole that this 'looks like what a software guy would do'

I am a software guy by trade and we 'think' in terms of modules and little blocks of functionality. and so when I build hardware it often is an exercise in integration more than outright design. little things wired together.

it looks a bit silly and for a pure hardware POV, it sort of is

otoh, each part can be swapped out and some other newer toy could be put in its place without ripping up whole main boards. so I like the piecemeal approach when I'm designing-as-I-go.

it really sounds good. kudos to tangent for the pimeta and amb for the dac. those guys did the real work - I just glued their stuff together!