125asx2 in btl ?

[bubuchef]

Hi everybody,


i bought a icepower 125asx2 from a friend .

i plan to use it in btl with asymetrical ( mono cinch) input.
i ordered a cable set from ghent, china.
but now , i am not shure how to connect the right input to get the correct btl

output !
can anybody help me, my wife fears the house is burning down, in case of wrong connection !😱


thank you for your help !
jochen ( germany )

 

[danschy]

I was looking at the module, although I don't have one. You can download the datasheet from the ICEpower website and consult fig 17 for the wiring (BTL sync pin is pulled low).

 

[bubuchef]

Hi danschy,
Thank you for your answer to my problem
I have read the application note about figuring the btl configuration, but sorry i so not know how to handle !
Does it mean to connect the btl pin to ground?
Sorry for poor english and poor knowledge !
Jochen

 

[danschy]

Yes, the BTL pin gets grounded. How are you doing the inverted input?

 

[Nisbeth]

You can't connect an unbalanced source to a BTL module directly (at least not if you want to get any benefit of BTL). However, before we go further - what do you want to power with a mono amplifier and what is the signal source?

 

[bubuchef]

An externally hosted image should be here but it was not working when we last tested it.

hi Nisbeth,
i`m planning to combine the amp with a guitar-preamp, see picture ( hopefully i did it correct )

 

[bubuchef]

Guitar/Instrument-Vorverstarker mit 4 Band Tone Control + Clip Detektor | eBay

 

[Per]

Ive used the attached board with two 125asx boards.

ghentaudio --- RTX (unbalnced RCA to balanced XLR Converting) Module

 

[bubuchef]

Hi Per,
no i don`t want to attach an other board, i just wish to connect my guitar-preamp with 125asx2 board.
a single source to the main amplifier input.
why can`t i just put the hot preampoutput to both inputs and connect the shielding to input ground and btl-pin ?
greetings
jochen

 

[Nisbeth]

Hi Per,
no i don`t want to attach an other board, i just wish to connect my guitar-preamp with 125asx2 board.
a single source to the main amplifier input.
why can`t i just put the hot preampoutput to both inputs and connect the shielding to input ground and btl-pin ?
greetings
jochen

Because it won't work. 🙄

- If you connect the hot end of a single-ended source to both channels then they are both "pushing" at the same time and the whole point of BTL is that you get more power because one amplifier "pushes" while the other "pulls". As a very stupid analogy think of being two people on opposite sides to open a door: If you both push it's not going to work 😀

- The BTL pin needs to be connected to the actual supply GND and not to the signal ground (and it's the same with e.g. the "enable" pin). If you just connect them to signal ground it doesn't work. Use the midpoint of the AUX-supply header or the mounting hole next to it as marked in the data sheet.

 

[danschy]

If you hook the same input to both channels you will get no output. A bridge configuration requires the two inputs to be 180-deg out of phase. Pulling the BTL input low does not provide the phase inversion between the two inputs. I've captured fig 17 from the spec and circled the functional block you need to add.

 

[Per]

You dont want to listen either?

 

[bubuchef]

thank you for your advice, i`ll try it out and will answer later when i was successful !

 

[Nisbeth]

.

 

[bubuchef]

thank you for your advice, i will try it later and tell you if it worked !
grretings
jochen

 

[MBA]

@bubuchef

Bad news:
- you won't get BTL without additional circuit - no way :-(

Good news:
- you can run the IcePower module directly from the preamp cinch in mono or dual mono mode
- you can even (presumably) power the preamp from the IcePower module - (check the power consumption of the preamp FIRST!!!)
- ich könnte Dir das auf Deutsch erklären, falls Du brauchst ;-)

 

[Turbowatch2]

Please, do yourself a favor and sell these modules at eBay, while they are still working. They brake easy and can NOT be repaired.
Take the money and buy the kind of amp you want at Thomann.
Not to listen to advice (you need a symmetric input signal) does not help in any way.

These are not amps without a case, but parts that need other parts constructed, to work.
You can use them for HIFI with small add on´s, but not for guitar or live music. There, they need extra protection. This is why they are not sold to DIYS purpose.

Bitte, tue Dir selber einen Gefallen und verkaufe die Module bei eBay so lange sie noch heil sind. Die ICE Dinger gehen extrem schnell kaput und sind leider nicht zu reparieren.
Dann nimm das Geld und kauf Dir was passendes bei Thomann.

Ratschläge die Dir nicht gefallen zu ignorieren, bringt echt nichts. (Du brauchst ein symmetrisches Eingangssignal, das Du nicht hast, sonst keine Brücke!!!)

Dies sind keine Verstärker denen nur das Gehäuse fehlt, wie Du vermutlich glaubst, sondern Teile eines Verstärkers, die mit anderen ergänzt werden müssen um dauerhaft zu funktionieren. Für HIFI Wiedergabe kann man sie fast so wie sie sind benutzen, aber auf keinen Fall für Gitarre oder andere Live Musik. Dafür brauchen sie noch diverse Schutzschaltungen, die sie nicht haben.
Darum werden sie auch nur an Hersteller verkauft, nicht an den Hobby Markt.

 

[bubuchef]

hi everybody,
thanks to all who helped me and extended my knowledge, but i see i have to give it up
and so i'm looking for an alternative poweramp !
greetings

jochen