Switching between Firstwatt F5 and AlephJ

[lykkedk]

Hi All here 🙂

I am in for building my F5 PCB's into the same chassis, as my alephJ.
I have my idea to try making a "switch" for switching between thoose two amp's.

They will have to share the same binding-posts, PSU and rca's.

Leftover from another project, i have a handfull of some omron G5LA-14-CF 12vdc; the spec. for such an relay is as this :

Coil Resistance: 400ohm
Coil Voltage: 12VDC
Contact Configuration: SPDT
Contact Current: 10A
Contact Voltage VAC: 277V
Contact Voltage VDC: 30V
Product Range: OMRON - G5LA Series
Relay Mounting: Through Hole

I have attached a schematic, i have been working on today, hoping to have some inputs from here, if i have to change something?

I am hoping, that i without problems, can make a common ground for all the GND connections?

RG; Jesper.

 

[Zen Mod]

it'll work ....... either as amp or as speaker burner



switching cold amp to hot psu is no-no in my book

you heard Papa Zappa's song ?

http://youtu.be/DlXePYM11ew

http://youtu.be/0elpH46dOyQ

 

[lykkedk]

LoL.. 😀

ZenMod!... please 😉

I am aware, that switching cold/hot, is no option. I will make it the way, so
no switching is possible, on the fly ofcause!

The mosfet's, will be drilled very close, to each Amp (F5, AlephJ) heatsinks.

Unfortunately, i have no pictures right here, of the inside of my chassis, but the mosfets, are attached at pure Alu' sinks... so nomatter what, the mosfets will be "hot", if i choose to power the amp. down and switch to other Amp.

I am planning, if neccesisary to also buildin speaker DC-protection/delay... but only when i tried the "clean version" first.

Any things to consider about the GND common connections ???

My chassis:

Schematics again:

Just a picture of my bare AlephJ pcb:

RG; Jesper.

 

[Zen Mod]

by hot/cold I meant on voltage state , not temperature

however , if you're going to switch between amp circuits while PSU is off and drained , go for it

regarding gnd - just make grounding scheme as for two completely separate amps and everything will be OK

 

[Zen Mod]

btw.

those are sissy amps

real men are using Babelfish ones

 

[lykkedk]

Thanks ZM..

I will post a GND schm. Tomorrow...

Btw: what do you think about the relays (Amp. Currency etc...?)

RG; Jesper.

 

[Zen Mod]

you have bunch of them

I didn't looked at your schm (hate that style - 'causing brainfart always ) while I looked at datasheet , but consider using at least two sections in parallel per rail

 

[lykkedk]

Cool enough...

But i cant' find any data, of how much currency(Ampere) of how much eg. The Alephj draws... Could it be simple :

200watt(pro channel) x 2 = 400watt... Then divided into 24volt = ~16ampere ?

Then i really need some bigger relays...

RG; Jesper.

 

[Zen Mod]

ya nutz ?



which Aleph J you're exactly building (what PSU and schematic)?

 

[OllBoll]

Are you sure you need a switch?

If the goal is to A/B switch then you could just use two identical speakers and connect one amp to each, where each amp has one channel. Then you can in the OS just pan from left to right to switch amp.

 

[Zen Mod]

dissipation is issue here , I believe

 

[OllBoll]

dissipation is issue here , I believe

In that case I'd say buying beefier heat sinks is a more simple solution 😉

 

[Zen Mod]

is there ever simple solution , when boyz from snowy regions are in question ?

 

[lykkedk]

Haha guy's...

I looked at Nelsons papers, saying that the Alephj dissipates around 200 watt, which must be around 8-9ampere!

So what i need is another relay(s) to switch the PSU from one set of pcb to the other set...

I will look, and see what i can find today in the range 30vdc ~20A or so.

RG; Jesper

ZM... Can you draw mockup of prefered gnd-schm?

 

[Zen Mod]

tonight

btw. current is twice Iq

go figure

wakoo Dane

 

[lykkedk]

ZM...

Looking forward to see, what gnd-schm you suggest...

RG; Jesper.

 

[lykkedk]

Evening all...

Just want to show a picture of my two Amp. pcb's; fully stuffed and tested!

RG; Jesper.

 

[Zen Mod]

lykkkkkk

grounding schm is easy

regarding gnd route :

just make complete wiring of one amp

then make complete wiring of second amp , completely ignoring first one

observe it like this - while one amp is connected to PSU , second one is floating , practically being non-existent

of course - switching is made only on pos and negative rails of both amps, while gnd route is permanent for both

 

[lykkedk]

🙂 ...Cool...

1. So i connect +23 and -23 seperately through relay(s)
2. +In left / +In right (RCA's) into Amp.A / Amp.B will be switched through relays too
3. Spk. out (+only) will be switched from Amp.A / Amp.B
4. Rest is GND, which will be connected as usual.

Well, when i move on, before all is assembled, i will post a picture where i draw in the GND connections...

thanks man!

RG; Jesper.

All messed up ::

 

[Zen Mod]

wakoo Dane