amplifiers for 8 - 8ohm speaker

I'm working on building a system that will consist 8 8ohm speakers for a sound installation in a small/medium art gallery.

I will play 8 different audio files from my 8 output audio interface.

I was thinking to use either those 30W speakers to those 8W speakers
is 8W speaker (or less) is enough for installation? (the sound is not need to be too loud for that application)

Which mono amplifier board is recommended?
How is the TDA2050 board for the mission? will it be needed to add fan for the 8 amp box I will build? or the heatsink is enough?

what shall I consider in choosing a board?

Thanks
 
Having replied to your other thread https://www.diyaudio.com/community/threads/building-boxes-for-speakers.406975/#post-7545812 relating to suitable speaker enclosures, I should say in this one that I agree with your choice of the 30 W drivers over the 8 W ones.

Having given this thread a nudge, other members may suggest suitable and reliable amplifier boards.

The power supply will require to have a high current capability in order to drive 8 amplifiers simultaneously.

If each amp is adequately heatsinked, a cooling fan should not be necessary, but the box containing them should be adequately ventilated.
 
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What @Galu said, just a couple doubts:

"8 audio files" ... Played in sequence or all at the same time?

If the latter: I know it's Art so it's free, but ..... 8 unsynchronized voices? .... it might approach cacophony.
Of course, that may be the intended effect

What is the program source?

Do you have an 8 output centralized source?
That requires 8 independent shielded cable runs.

Or you will build an 8 amplifier rack and run 8 independent speaker cables?

What's the longest expected cable length?

EDIT: TDA2050 is obsolete and dead by now, although there are some off brand replacements.
If you buy ready built Asian ones they "should" work, they will source and fit "something" vínculo the boards.

I would buy a couple extra boards as spares.

You will need a large cabinet, proper heatsinking, proper power supply.

Build and setup the system well in advance to test it well, not with people queueing outside impatient to get in.

I am known among Argentine Rock Musicians for soldering some Mod in an amp on stage while people was being admitted, at Luna Park, our Madison Square Garden version. 😱
 
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"8 audio files" ... Played in sequence or all at the same time?
Mostly sequence. Might be some time that they all play along.
If the latter: I know it's Art so it's free, but ..... 8 unsynchronized voices? .... it might approach cacophony.
Of course, that may be the intended effect
It will be harmonized.. Or intended cacophony 🙂
Do you have an 8 output centralized source?
Yes, I'm using this 8 output RCA unbalanced
Or you will build an 8 amplifier rack and run 8 independent speaker cables?
I'm building one amplifier box with 8 of those mono amplifiers. using this 24V 350W
What's the longest expected cable length?
10 Meter. I am planning to use speaker cable 0.75mm2 using powerconn connectors


Edit - some of the stuff regarding powering the mono amplifier was discussed in here
 
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You will need a large cabinet, proper heatsinking
Here is my plan for the box.
Size is 550mmx325mm with Depth of 155mm
 

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Here is my plan for the box.
Size is 550mmx325mm with Depth of 155mm
In general, fine, although not too sure about all that fitting inside such a small box.

Try it first on a piece of paper, drawing a rectangle on it and physically placing all boards in place, power supply, connectors, switches, IEC connector, everything.

Drawing rectangles on screen is a necessary beginning but does not give you the real idea of physical space use.
Only after that purchase the proper case.

Leave 40/50 mm around each board, power supply module, etc. , 40/50 mm "free" space along front and back panels for connectors and wiring.

You show 2 fans, hope "6 mm" is a typo.
Use 1 or 2 24V PC type fans (3" to 4") on one side (say, left) and punch ventilation holes on the opposite side.

No need for a "hurricane" but you want a good steady flow across so those built-in heatsinks can do their job.
Being efficient Class D not a big deal if it was a single amp but you are cramping 8 of them into a small case.
Plus the power supply.

I am planning to use speaker cable 0.75mm2 using powerconn connectors
You mean Speakon connectors?
Powercon are intended for Mains.
Never use them outside their specific use.
Of course you can use one for power supply Mains.
In any case, speaker connectors must be isolated from ground, those amp outputs are balanced/bridged.

Keep us updated, in due time post amp and cabinet pictures and later some on your actual Art installation.

Even link some YT video of it in action 🙂

Almost forgot: saw Visaton offers matching protective grills: use them.
Floor placement of small speakers is dangerous, it's easy for somebody to kick cones in, destroying them.
 
What band!? We listen to a lot of good music from Argentina in our house.
You have good taste 😉

Most of them, been supplying Argentine Rock since it's very beginning in 1969.
Over 14000 amps delivered to almost 10000 customers.
Some of them: Charly García, Nito Mestre, León Gieco, Pappo, Crucis, Pastoral, Rata Blanca, Almafuerte, La Renga, Vox Dei, El Reloj ... impossible to name them all.
Plus non-rock Artists (Tango - Folklore Jazz) such as Mercedes Sosa, Beba Pugliese, Les Luthiers, Xeito Novo, or backline for international visiting artists such as The Platters, Baron Rojo, or full PA system for Moscow Circus, Buenos Aires Planetary or custom multi-headphone systems for recording studios.
Being the "go to" guy for "anything you can't find at a local Music Shop", which is both a blessing (lots of work) and a nightmare (most jobs are stressful "one of a kind").
Oh well, can't complain 🙂
 
You show 2 fans, hope "6 mm" is a typo.
Use 1 or 2 24V PC type fans (3" to 4") on one side (say, left) and punch ventilation holes on the opposite side.
That is the fan I wanted to buy. 6mm was indeed typo. it size is 80mmx80mmx25mm.
I chose this fan because it suppose to be very quiet.
I was thinking to place one fan on left size to push air inside the box and another fan on the right side to pull air out of the box. Is it too much?
Drawing rectangles on screen is a necessary beginning but does not give you the real idea of physical space use.
Only after that purchase the proper case.
Thanks for that tip. I will defiantly

wait until all materials arrives before cutting and building the box.

Being efficient Class D not a big deal if it was a single amp but you are cramping 8 of them into a small case.
Plus the power supply.
The power supply will sit in a different box

You mean Speakon connectors?
Yes (I think) I bought those sockets and connectors for the speaker wires

In any case, speaker connectors must be isolated from ground, those amp outputs are balanced/bridged.
With the above connectors I bought - It will be isolated from ground right?
Keep us updated, in due time post amp and cabinet pictures and later some on your actual Art installation.
I will. I hope that in a month time all the materials will arrive and I will be able to start building

Thanks for all the kind help
 
In any case, speaker connectors must be isolated from ground, those amp outputs are balanced/bridged.
here is a diagram of how I thought of connecting the amp output to the speakon connector:

a 2 wire speaker cable will connect between the amp and the driver.
Is that make sense? Is this considering isolated from ground?
 

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here is a diagram of how I thought of connecting the amp output to the speakon connector:

a 2 wire speaker cable will connect between the amp and the driver.
Is that make sense? Is this considering isolated from ground?
Yes.
Actually it will be:
2 wires from each amp speaker out to Speakon chassis connector 1+ and 1- (they are so labelled)
Speaker cable with Speakons at each end.
2 speaker wires to 1+ and 1- connector pins.
Nowhere is any cable connected to chassis or supply ground.
My warning was because some metallic connectors, say 6.35mm guitar jacks, RCA, etc. "automatically" self ground on mounting, unless specially insulated.
No problem with plastic connectors.

As of ventilation, guess 2 fans won't ve needed, just one, but be certain to have vent/exhaust holes on the opposite side.

Horror stories sometimes are real, I once repaired a rack mount power amp with a fan mounted on one wall injecting fresh air into the cabinet... and no exit holes to speak of, besides jack holes 😱

Internal heat sinks of course.
 
The fan looks fine.
As said before, you don't need a hurricane, no steaming hot Class A heatsinks present, you simply need to replace hot air inside cabinet with fresh one.
I suggested a 24V fan so it can use same supply as amp boards.

Try to use 1mm² wire if available.
Here it costs same as 0.75mm².
If possible get the red-black "speaker" type to make it easier keeping phase.

That said, don't worry about power losses in this particular (Art Gallery) use, 10 meters is no big deal and highest power is not needed anyway.

I imagine walking around enjoying your Art and to hear whispering female voices coming out of nowhere or everywhere 😄

I live in an Art dedicated part of Buenos Aires, surrounded by Painters, Art Galleries, Museums, Ateliers and a Theatre.
You should show your Art in Fundación Proa, a Modern Art Museum just around the corner:
http://proa.org/eng/exhibiciones-proa-actuales.php
 
Try to use 1mm² wire if available.
Here it costs same as 0.75mm².
If possible get the red-black "speaker" type to make it easier keeping phase.
You mean this type of speaker wire right? Without the plastic insulation on top the two wires
What the disadvantage of using this type?
I could think of easily the two conductor will separate from one another?
 

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I might be overthinking it but - Is adding holes on the top of the box for ventilation in addition to the two fan I will put is something I should do or not do or doesn't really matter?

(I decided to put two of the 80mm fans - one pull air and one push air)