Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => The Newcomer's Forum => Topic started by: Oooscar on January 14, 2022, 07:22:21 PM

Title: Getting nice sound for the low strings (low frequencies) on a small speaker
Post by: Oooscar on January 14, 2022, 07:22:21 PM
Hello,

I have around two small speakers from a pair of phones. 8 ohm 0,25 watt each one.
I have tried It today with an lm386 amp I have. And the sound from the low strings is not as good as the sound of the first three ones. I know small and tiny speakers have problems with low frequencies, I even tried It with the smartphone, and It sound quite high, bright, treble. Is there any way to balance the sound at least a bit? Changing the output capacitor, etc. I would like to make a very small guitar amp, like a smokey amp, but with the "best" possible sound.

Regards, cheers
Title: Re: Getting nice sound for the low strings (low frequencies) on a small speaker
Post by: Enzo on January 14, 2022, 08:17:58 PM
Low end from tiny speakers?  Not likely.  To make bottom, the speaker cones have to move sufficiently to make the wave fronts.  That is hard for a speaker to do with a movement of a millimeter or so.
Title: Re: Getting nice sound for the low strings (low frequencies) on a small speaker
Post by: phatt on January 15, 2022, 08:27:56 PM
If the speakers are not in a box then Bass will be non existent.
Especially being that they are H phone speakers (As Enzo noted)
Even a small cardboard box will improve the bass a little.
Phil.
Title: Re: Getting nice sound for the low strings (low frequencies) on a small speaker
Post by: Enzo on January 15, 2022, 09:54:29 PM
Reminds me, in my shop days, when I had a speaker sitting out and wanted to test it with music.  Just a brief test.  They sound awful sitting on a table, so I would reach over and hold the speaker facing up over my trash can.  That enclosed space under the speaker gave it enough of an enclosure to see if it sounded halfway decent.
Title: Re: Getting nice sound for the low strings (low frequencies) on a small speaker
Post by: phatt on January 17, 2022, 12:22:28 AM
Makes  me smile Enzo, Yep my bin is the perfect size for a 12" speaker. :cheesy:
If I want to get an idea of how big to make a box I shove pillow in the bin which of course alters the volume.
Oh I do empty the bin first :lmao:
Phil.
Title: Re: Getting nice sound for the low strings (low frequencies) on a small speaker
Post by: Tassieviking on January 19, 2022, 09:26:30 AM
The only tiny speakers I have ever noticed decent sound from are in soundbars or computer speakers, a very few of these sound ok, sort of.
They are meant to be small with big sound, but I imagine they might sound crap if you take them out of the housing they are in.
If you find some cheap at a tip shop or second hand shop it might be worth a try.
I have a small sound bar on my computer which can get fairly loud, the speakers are very small in it, I'm sure I could drive it straight from a preamp pedal.
I have a Sunn Beta Lead pedal I might try it with one day.
Title: Re: Getting nice sound for the low strings (low frequencies) on a small speaker
Post by: joecool85 on January 19, 2022, 11:06:24 AM
Honestly, the best way to make small speakers sound good is to remove the bass frequencies until they stop "farting" when you play.

Past that, choose a small speaker with the best frequency range - at least 100hz to 5,000hz.  Normally high end is fine, you can focus on the low number.  If much higher than 100, it just won't have any bottom end at all.

Next you need to pay close attention to SPL.  The SPL rating will be dbm/w meaning that it is the volume of the speaker using 1w of power at 1 meter distance.  The higher the rating, the louder it will be with the same power versus another speaker.  Many cheap small speakers have SPL ratings of 75-80dB.  I recommend at least 90dB.  Comparing an 80dB speaker with a 90dB speaker at 1w, the 90dB will be exactly twice as loud!

Here is the best small speaker I've found so far: https://www.parts-express.com/Visaton-R10S-4-Full-Range-Speaker-8-Ohm-292-596

I sell this with the Honey amp kits.  It is "ok" sounding, but about the best I've heard from small inexpensive speakers.  Like mentioned above, to make any speaker sound "right" means paying attention to the enclosure.  Open air most speakers sound terrible - even large ones.

For reference, most 10" and 12" guitar speakers have ranges around 80-85hz to 5,000hz or so and SPL ratings between 93dB and 101dB.