TPA3118 60W Power Amp Module
- Thread starter falzhobel
- Start date
Mike McLane
Active member
I came across this the other day. . . .
A little extra money, but no counterfit chips, crappy or marginally sized components. You can find Jerry's website here:
A little extra money, but no counterfit chips, crappy or marginally sized components. You can find Jerry's website here:
Jerry's Electronics - Maker of Simflame, JEMP3, Electronic Kits and More
Jerry's Unique Electronics
www.jerryselectronics.com
First post, discovered this thread when looking into building a Class D guitar amp.
I totally agree with what you've said. But aside from needing to boost the input signal, I think the other factor at play is an impedance mismatch. My understanding is that the TPA3118 has an input impedance of only about 30k ohms....nowhere near the 1 meg of a typical guitar amp. So any preamp will have to take this in account. Cheers!
Any idea when? Asking for a friend...It's going to be a pedalboard-mounted power amp project.
Mike McLane
Active member
Nothing's popped up lately with respect to these boards. I've recently completed a couple of Sushibox builds (tube driven preamps) and am curious about the relationship btw the output of the tube preamp and the input requirements of a typical Class D amp or PA mixer. I understand both want to see a line level signal which is what. . . 2 or 3 volts peak-to-peak? Also, impedance matching. . . tube preamp output impedance is around 38K. Is that good, bad or indifferent with respect to the input requirements of amp/mixer?
FWIW, I built a small LPB1 buffer board with a trim pot and placed it inside a 1590BB box using one of these small amps. It works really well with the output from the Sushibox tube builds.
Mike McLane
Active member
Hmmm? . . . that's a booster isn't it? A tube preamp is putting out 20+ volts isn't it? Don't you need to reduce the output of the preamp? That can be done with the Master Volume. But to broaden the useable sweep of the MV I was wondering about adding a resistor or voltage divider network in advance of the MV. Maybe on a toggle so you can switch btw use with a Class D/mixer or in an FX loop in a conventional amp.
I have had the power amp with the buffer/boost built for a few years and am just noting it works well with the output of the tube preamps. They work well at either end of my pedal chain, so I don't think that is too surprising. There probably is enough output from the Sushibox pedals to not need the buffer.
Mike McLane
Active member
Anybody up to snuff on power supplies? I hooked up my little TPA3118 amp board with just 19vdc 3A laptop power supply and IN/OUT jacks . . . no volume pot or related caps, etc. as shown in the layouts above. Talk about HUMMMMMMM?!? What I've read is that most laptop PSU's are not grounded and that is the source of much of the noise. I was looking at the Meanwell EPP-200-24 which is an open frame PSU that could be placed in the same enclosure as the amp board and fed with 120vac, but none of the hook-up pins show a dedicated GRD for a 3-prong power cord. Any words of wisdom on this subject would be appreciated.
Alan W
Well-known member
Not the help you need. I looked at the datasheet, and it says “grounding required” under the input terminal descriptor. I‘ve used many Meanwell supplies, mainly ones in perforated enclosures, and have a strong memory of their having a green screw for ground on them, but the datasheet, beyond that mention of grounding required, doesn’t have any details. I didn’t go to the Meanwell site to look at their manuals section—the datasheet refers this for installation, so it may be answered there. If still no sure answer, the grounding the enclosure it’s in would be my take.
Note that there is a specific 12 v output for a cooling fan, which they say is needed for full output. I’d be wary of putting this in a small sealed stomp box, in terms of heat. If you do go a small fan route, best practice is to have the fan exhaust, and have intake holes on the other side, so you get cross draft.
I haven't had any issues with the 3118 or 3116 in terms of noise. It can vary a little between power supplies, but I've found the higher wattage amps to be terrible for noise - to the point of not using them, lol. I have a couple around that will need proper transformer based power, but as far as laptop powered boards, it seems like the 3118 and 3116 are they way to go.
First post here folks. Originally posted in the wrong thread whoops! Great forum! I went down the rabbit hole on this thread and now have all the parts to assemble this thing. I will be putting this in a combo style cabinet with a 15" I have, which used to house a Tweed Deluxe clone. My knowledge of electronics is like Swiss cheese, but I have built 2 tube amps and just finished my first pedal and all work very well. The pedal is a clone of a JJ-150 and I plan on using this as the preamp for the TPA3118. I am building it on an eyelet board similar to the tweed amps I cloned. I am putting the buffer on the board next to the preamp before it goes into the power amp. Got a cheap buck converter off Amazon for changing the 19v PS to 9v. I plan on using a dpdt on-on-on switch for a combo standby - on - off switch, wiring to the mute on the TPA3118. Got the plastic isolated jack for the output. Throw it all in a blender and I am hoping for the best!
My concerns... My speaker is only rated for 30 Watts so hopefully it doesn't blow. I am thinking should be fine with 19v PS. I am also thinking a type of soft limiter would be good, but really over my head and I can't find much about these outside of this thread. https://www.diyaudio.com/community/threads/a-tubey-solid-state-soft-limiter.356785/
This thread describes what sounds like a very well designed ss amp using this limiter.
www.diyaudio.com
I would like to add something like this limiter, or a compressor of sorts but this thing is getting a bit complicated! Any thoughts or concerns?? Thanks!
My concerns... My speaker is only rated for 30 Watts so hopefully it doesn't blow. I am thinking should be fine with 19v PS. I am also thinking a type of soft limiter would be good, but really over my head and I can't find much about these outside of this thread. https://www.diyaudio.com/community/threads/a-tubey-solid-state-soft-limiter.356785/
This thread describes what sounds like a very well designed ss amp using this limiter.
the trAmp - my latest and smallest guitar amp
The TrAmp – my smallest guitar amp Over the years I designed a lot of guitar amps for my private application. So I never had to care about any marketing aspects – it is my own taste that counts here, and I am free to choose the best of all solutions available. For a lifetime I played DIY-amps...I would like to add something like this limiter, or a compressor of sorts but this thing is getting a bit complicated! Any thoughts or concerns?? Thanks!
Alan W
Well-known member
First off, welcome to the forum!
if your main concern (in terms of adding limiters, etc. ) is the speaker rating, I wouldn’t be too concerned, unless your plans for this are less practice guitar amp and more outdoor venue performance. That 15 inch speaker is probably efficient enough that your typical indoor output will be a watt or two into it.
if your main concern (in terms of adding limiters, etc. ) is the speaker rating, I wouldn’t be too concerned, unless your plans for this are less practice guitar amp and more outdoor venue performance. That 15 inch speaker is probably efficient enough that your typical indoor output will be a watt or two into it.
It's for steel guitar. I'm not planning on venues, but I do like to crank it up to get a little breakup. The jj-150 preamp is amazing at mimicking that 40's- 50's mid focused tube amp sound through my Quilter Superblock and even sounds really good through my little Fender Frontman. I am curious how it will work through the TPA3118? Only one way to find out! I am anticipating that it may still need something. I am leaving a place for another knob where a limiter type control will eventually go, just not sure exactly what type of additional circuit will work best. Just for fun I will wire a dying battery simulator in this spot, so I can also kill the voltage to the preamp and experiment with other preamps, yet still use the buffer. I am not sure how the Fetzer Valve thing works with the TPA amps, but it seems worth trying. Other preamps I want to try are ROG Professor Tweed and ROG Tonemender.
I built a proper Deluxe cab and transplanted the chassis cause this thing was pretty heavy and I really just wanted something SS and light with a bit more headroom for steel guitar. I still love the old tweed tones though. That is how I ended up here.
I built a proper Deluxe cab and transplanted the chassis cause this thing was pretty heavy and I really just wanted something SS and light with a bit more headroom for steel guitar. I still love the old tweed tones though. That is how I ended up here.
JTEX
Well-known member
I hope you guys don't run into the kind of problems I ran into with my TPA3255 board from Amazon. I found the overload protection too aggressive for use with musical instruments (very "peaky", dynamically, compared with mixed music material). When playing, for instance, slap bass through a TPA3255, the strong peaks would be seen as an overcurrent event, causing the chip to go into protection (shutdown) and stay there until you power cycle it. There was nothing I could do about it.
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KindCanuck
Well-known member
I have built a 3110 board and it’s on par with my Princeton, so yeah it works great!
