Hi,
I am planning a class D guitar amp:
Ideally it should be full range - so it can be used for other instruments ... if needed. I need advice ... especially for speakers. Coaxial would be preferred, but with max price around 100 USD per piece. Other ideas are also welcome.
I someone has made similar build ... I would be happy if he/she could chime in.
cheers
I am planning a class D guitar amp:
- TPA3255 based amp
- stereo 2 x 120w into 8 ohm
- either 6.5" or 8" speakers
- coaxial or extended range
- compact enclosure
Ideally it should be full range - so it can be used for other instruments ... if needed. I need advice ... especially for speakers. Coaxial would be preferred, but with max price around 100 USD per piece. Other ideas are also welcome.
I someone has made similar build ... I would be happy if he/she could chime in.
cheers
What are you feeding the amp with? What type of music will be played through it? Clean, distorted? A lot of the flavor of the guitar comes from the speaker. Not much in the way of real guitar speakers under 8", why fight to get any volume with a 6.5" either way. A Champ puts out a whopping 5W, I wonder on the 120W.
The build has more similarities with active studio monitor or PA speaker than with normal guitar amp. Digital profiler/modeler is a simulation of amp&cab together. So ... less speaker color the better. 120w from class-D is not that much.
I play mostly clean, but have some projects with fuzz and hi-gain sounds.
I play mostly clean, but have some projects with fuzz and hi-gain sounds.
I would not go with coaxial's, blow a tweeter then you are out the whole speaker. Next is how loud you want to get. If you are setting up to play with your laptop then an inefficient (relatively) is not a big deal. I can not remember the maker, I think Quilter, used a full range Celestion (not guitar speaker) in a combo that has been well received. I think it might be this one.
https://celestion.com/product/tf0818/
https://nextgenguitars.ca/products/celestion-tf0818-100w-8ohm.html
Did find a source saying it is the one.
https://www.thegearpage.net/board/index.php?threads/can-an-8-speaker-cut-it-live.1560715/
https://celestion.com/product/tf0818/
https://nextgenguitars.ca/products/celestion-tf0818-100w-8ohm.html
Did find a source saying it is the one.
https://www.thegearpage.net/board/index.php?threads/can-an-8-speaker-cut-it-live.1560715/
Maybe you missed:
Here that flattest most neutral speaker is best.
No guitar speakers there but a full range or coaxial type.
Preferably a PA type if available, for the extra sensitivity and power handling.
.
A Champ is used full blast squarewave distorting if needed.
This amp must be always clean.
Low sensitivity and clean sound means higher than.normal power to get some headroom.
You will have a heart attack when you see modern FRFR powered guitar cabinet specs:
https://www.headrushfx.com/products/frfr108/index.html
Single 8" speaker, 2kW power amp.
If you ask me, a truckload of organic fertilizer, but hey .....
HeadRush FRFR-108®
The HeadRush FRFR-108 is a lightweight 2000-watt full-range, flat-response powered cabinet that perfectly complements your HeadRush Pedalboard, Gigboard, or any other multi-FX/amp modeler to give you a realistic room-filling sound with the authentic feel of a speaker pushing air.
Yes, but that one drops after 6khz. I would not call that full range. Although it is interesting why FRFR guitar cabs need full range response? Typical guitar speaker range is from 80-5000hz. Nothing after this.
Just guessing: maybe they want software to choose rolloff frequency, slope, and peaks.
That would require wider response than normal, simply to fully remove speaker from the equation.
Also some might simulate Acoustic Guitar amps or include wider than normal range guitars, such as Parker Fly with their bridge mounted Piezo pickups.
FWIW I added an under bridge Piezo pickup to my "shop" Bass Guitar customers use to try amps.
There are some high harmonics which are obviously produced (you can hear them) but usually
never heard from a conventional Bass guitar.
My Bass cabinets also include Tweeters, and are much loved by slappers and Fusion style Bass players.
My Bass heads even include a "Slap" switch, which creates and brings out all kinds of harmonics.
Here, the bottom one:
That would require wider response than normal, simply to fully remove speaker from the equation.
Also some might simulate Acoustic Guitar amps or include wider than normal range guitars, such as Parker Fly with their bridge mounted Piezo pickups.
FWIW I added an under bridge Piezo pickup to my "shop" Bass Guitar customers use to try amps.
There are some high harmonics which are obviously produced (you can hear them) but usually
My Bass cabinets also include Tweeters, and are much loved by slappers and Fusion style Bass players.
My Bass heads even include a "Slap" switch, which creates and brings out all kinds of harmonics.
Here, the bottom one:
@Harehare what are you considering for a preamp to provide color adjustments that can easily drive a TPA3255 to full power? For bass 've a mono FosiTPA3255 driven by a Caline "Wine Cellar" pedal - speaker is a Celestion K12H-200tc in an old diy Karlson K12.I'd like to know if a Joyo Actone pedal can drive TPA3255 to full power iwth average guitar pickups (generic Strat/Tele)_I've got so much tendon pain in both arms that can't even hold a guitar anymore
I am using toneX. I am not sure what you mean with "full power"? Volume control and tone controls can be installed on the TPA3255 board ... maybe this one. It is a bit more fancy and expensive, but has everything onboard.
You need proper power supply to achieve max output from TPA3255. Do you drive Fosi it with 48V?
You need proper power supply to achieve max output from TPA3255. Do you drive Fosi it with 48V?
Thanks. The stock 32v 5A supply is plenty enough to get me thrown out of a trailer park. RE: full power - I don't know the real input sensitivity of my Fosi amp. Other amplifiers I've owned throughout the years were spec-ed at "2 volts" to reach rated power- onset of clipping. I'd like to know if the Joyo Actone or American pedals could drive an average power amplifier with a typical Strat/Tele style guitar - or whether there would be sufficient gain at clean settings. For a rough jam sans durms a TPA3016 running off a 20v tool battery could suffice.
I think that guitar pedals have lower output compared to line output. I think you need some sort of preamp before the TPA board. Don't know much about electronics ... I am beginner - this is my first build.
And after his response I got what he was looking for and gave him my best suggestion that was used by Quilter. Sorry for being so slow and missing things. I got off a medication three weeks ago and have been averaging about four hours sleep a night.
And a tweeter on top of that would work I would think. I suggested not getting a coax that way the tweeter can be replaced if blown (doing any high gain solos?)
Thanks, but that complicates things for me - it is my first build. I am not able to make crossover. I am looking at coaxial speaker with 150Wrms/300W max and factory crossover installed. These could be expensive ... 100$ per piece.
Other option is ... lower power full range (maybe Visaton BG17) and later upgrade ... if all goes well 🤔
I can reuse these (if not blown by amp).
As they say, a picture is worth a thousand words, moving pictures....
This might help you more than anything I can say.
This might help you more than anything I can say.
Last edited:
I built a pair of 1.8 cubic foot cabinets with some cheap drivers from Parts Express. Each cabinet has two of these 6 inch drivers and a Pyle bullet tweeter. The tweeters make the sound of a distorted guitar way too harsh so I keep them turned off for guitar even with a 4 watt tube amp. The tweeters do add some nice sparkle to the electric piano preset on my old Roland JV1000. I have fed the cabinets with a TPA3255 at full tilt on 48 volts. It sounded great with several guitars, the JV1000 (tweeter off) but things started to sound like a blown speaker after about 10 minutes of hammering them with a bass guitar. Autopsy revealed that the speaker drivers were OK, I had just rattled all the mounting bolts loose!
https://www.parts-express.com/Dayton-Audio-PA165-8-6-PA-Driver-Speaker-295-015?quantity=1
I got a deal on four Faital Pro 6FE200 drivers so I swapped them into the cabinets. They are louder but give up a bit of low end which is most notable with the keyboard or bass guitar. The Faitals will also get much louder before speaker distortion sets in, as they are rated for 130 watts RMS each. They are also about twice the price here in the US. The Faitals come from Italy so the price difference will be different in your end of the world.
https://www.parts-express.com/pedocs/specs/294-1151-faitalpro-6fe200-4-specifications.pdf
I am building a bi-amped guitar cabinet and amp head that will use two of the Faitals and a 15 inch Dayton PA driver, so I am planning to put the Dayton 6 inch drivers back in the in the small cabinets.
https://www.parts-express.com/Dayton-Audio-PA165-8-6-PA-Driver-Speaker-295-015?quantity=1
I got a deal on four Faital Pro 6FE200 drivers so I swapped them into the cabinets. They are louder but give up a bit of low end which is most notable with the keyboard or bass guitar. The Faitals will also get much louder before speaker distortion sets in, as they are rated for 130 watts RMS each. They are also about twice the price here in the US. The Faitals come from Italy so the price difference will be different in your end of the world.
https://www.parts-express.com/pedocs/specs/294-1151-faitalpro-6fe200-4-specifications.pdf
I am building a bi-amped guitar cabinet and amp head that will use two of the Faitals and a 15 inch Dayton PA driver, so I am planning to put the Dayton 6 inch drivers back in the in the small cabinets.
Attachments
I have a TPA3255 EVM from TI for the amp, and I used an ADA MP-1 for the preamp. I did not use any pedals since the MP-1 has lots of FX. The MP-1 has a stereo output, so I set the EVB up for two 300 watt channels and put one cabinet on each channel's output.
What do you feel about adding passive tone controls before TPA? Vol/treble/bass would be nice to have, but will it degrade the signal? What about active preamp module?