#27 is alive and singing on the bench. I’ll cook it for a while and re adjust 20V. It is dead quiet on my headphone tester. Next test will be on my horns 500 Hz and up. This amp sounds glorious on the test speakers! Good thing I’m taking the day off of work tomorrow. I envision a late night of listening!
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Congrats! Enjoy! I was listening to this amp up till 3am last night... and I don’t envision tonight being any earlier either.
My amplifier is close, just a few more wires to go. I did run out of orange and had to dig through my junk pile to find another piece to keep it all color matched. I'm doing something slightly different with my build regarding the FE boards. I will share a picture when it's finished. Everything has gone together well, final assembly is kinda interesting with 5 pcb's / associated wiring in a bit of a tight space. I did use the screws the chassis came with along with some washers I found to mount the OS bracket to the heatsinks.
Cooked. Set. Now in the big rig.
It’s running 500hz and up into JBL 375s and Fostex T925As
Nelson, you have hit a grand slam with this design!!!
Thank you to Nelson, Jason, Mark, Jim, and anyone else involved!
It’s running 500hz and up into JBL 375s and Fostex T925As
Nelson, you have hit a grand slam with this design!!!
Thank you to Nelson, Jason, Mark, Jim, and anyone else involved!
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Not 100% classics. I'm running a pair of JBL Hartsfield reproductions. The cabinets are probably ~20 years old. The drivers are classic JBL. The 375 compression driver has a steep rolloff at 10k, so I added Fostex super tweeters based on the suggestion of JBL expert John @ Classic Audio Reproductions. I have removed the original crossovers to make the system active. So you can say it's a classic design, modernized.
As I learned to say when working in DK... "It could be worse."
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Sub is behind The Trooper. It wasn’t in the picture because it is in the back of the room.
None of the speakers are light weight! As we all know - you can’t break the laws of physics!
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re power switch at the back
How about trying one of these.
Enchufe Inteligente, Mide el Consumo 16A 3680W Wi-Fi Smart Plug, con Control Remoto Meross App. Compatible con Alexa, Google Assistant y SmartThings. Paquete de 4.MSS310: Amazon.es: Bricolaje y herramientas
https://www.amazon.com/meross-Smart-Plug-HomeKit-Pack/dp/B084JHJBQT/ref=sr_1_1_sspa?dchild=1&keywords=meross+smart+plug+B08PF3R4BG&qid=1619165441&sr=8-1-spons&psc=1&smid=A23Q57EDICDOV3&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzMzNUU09QUDMyWjM1JmVuY3J5cHRlZElkPUEwNjMwMzMyMkJHM1U0RkFVRlM5RSZlbmNyeXB0ZWRBZElkPUEwNzk0MzE2Ulk5TktYRVAyODg2JndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==
they are 15 - 16 ampere.
2 channels at 36 volt and 1.6 ampere makes 115 watt.
on primary this is around 1 ampere on 110 volt systems and
around half an ampere on 220 volt systems.
with this one you can turn the amplifier on and off whith your smartphone.
you can check on your phone if you forgot to turn off your amplifier.
you can turn your amp on when you leave work for it to warm up for when you get home.
I think this would work fine with this amplifier having SMPS.
I would not use this on a linear supply unless you have a well designed and effecive soft start.
if someone with more knowlege on this think it is a bad idea, please let us know.
How about trying one of these.
Enchufe Inteligente, Mide el Consumo 16A 3680W Wi-Fi Smart Plug, con Control Remoto Meross App. Compatible con Alexa, Google Assistant y SmartThings. Paquete de 4.MSS310: Amazon.es: Bricolaje y herramientas
https://www.amazon.com/meross-Smart-Plug-HomeKit-Pack/dp/B084JHJBQT/ref=sr_1_1_sspa?dchild=1&keywords=meross+smart+plug+B08PF3R4BG&qid=1619165441&sr=8-1-spons&psc=1&smid=A23Q57EDICDOV3&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzMzNUU09QUDMyWjM1JmVuY3J5cHRlZElkPUEwNjMwMzMyMkJHM1U0RkFVRlM5RSZlbmNyeXB0ZWRBZElkPUEwNzk0MzE2Ulk5TktYRVAyODg2JndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==
they are 15 - 16 ampere.
2 channels at 36 volt and 1.6 ampere makes 115 watt.
on primary this is around 1 ampere on 110 volt systems and
around half an ampere on 220 volt systems.
with this one you can turn the amplifier on and off whith your smartphone.
you can check on your phone if you forgot to turn off your amplifier.
you can turn your amp on when you leave work for it to warm up for when you get home.
I think this would work fine with this amplifier having SMPS.
I would not use this on a linear supply unless you have a well designed and effecive soft start.
if someone with more knowlege on this think it is a bad idea, please let us know.
possible transformer specs
not shure, but in case I want to make a classic transformer-CRC supply:
I already have a 27-0-27V 200VA Torroid.
I know that we use (at least) 300VA for normal FW iterations, but this one dissipating a little less, so 200 VA should be ok, right??
-can i expect 27x1.4= 37,8V from this (maybe little less)? Not shure how much "on the edge" we are with the 36 V SMPS, do you thing a little higer will be critical?
to be clear, it is not a ressentiment against the SMPS solution, which is probably even more quiet ..: ), I just have those donut lying around..
best,
stefan
not shure, but in case I want to make a classic transformer-CRC supply:
I already have a 27-0-27V 200VA Torroid.
I know that we use (at least) 300VA for normal FW iterations, but this one dissipating a little less, so 200 VA should be ok, right??
-can i expect 27x1.4= 37,8V from this (maybe little less)? Not shure how much "on the edge" we are with the 36 V SMPS, do you thing a little higer will be critical?
to be clear, it is not a ressentiment against the SMPS solution, which is probably even more quiet ..: ), I just have those donut lying around..
best,
stefan
Each channel dissipates roughly ~60W, a 200VA for both channels will most likely be around 1.2, maybe less.
If I were choosing a transformer, it would be a 300VA model with 28V secondaries. My experience with the ACA amps was that 300 VA was necessary to prevent excessive voltage drop. It is also important to use bridge rectifiers with low forward voltage drop.
Using a factor of 1.4 is too optimistic. 1.3 is a better indicator of final voltage.
Using a factor of 1.4 is too optimistic. 1.3 is a better indicator of final voltage.