Well, ermm...cough...let me explain what greed is...greed means...you're loaded with money and 16 x 10000uf/100V is a fortune!
I bought 10 X 8200uF @ 100V for $30USD (Apex Jr. - on this site, vendors ) ... no fortune. Just shop around...
VERY NICE , Lee !!!
OS
exotic
Congratulations to Lee. leds looks very exotic. Have you finished the project?
I think so for this device to need a good box design. Device, how was performance? power, sound distortion and brilliance?
Lee...
my school is organizing an activity.
I need an amplifier 2000watt until 19 May. amplifier now have in my hand a working 1000watt. but not enough. because it is not enough for the stadium.
Congratulations to Lee. leds looks very exotic. Have you finished the project?
I think so for this device to need a good box design. Device, how was performance? power, sound distortion and brilliance?
Lee...
my school is organizing an activity.
I need an amplifier 2000watt until 19 May. amplifier now have in my hand a working 1000watt. but not enough. because it is not enough for the stadium.
May 19th is a very short deadline for such a project.
This is one of the things I enjoyed - no deadline.
However, you can count on my support.
The last thing missing is a housing. First I wanted to have the interior complete and working. I have a concept already but I'm far from having usable drawings.
I enjoy great sound at the moment but I think this is not affected by the amplifier in any way. I believe amplifiers are actually inaudible. This is something one could debate about endlessly.
I fixed my old crappy DIY active crossover and this improved the sound remarkably since I can use the 15" bass speaker again. I hate the bass from my cheap Sony speakers. I love bass and need kick instead of undefined boomy "whooomphhh".
Doing the calculations to match amplifiers and speaker sensitivity showed what such a high powered amplifier is good for: Driving inefficient loudspeakers. Want more dB? Get more efficient speakers!
A little calculation (I hope I did it right, please correct me if I'm wrong):
The Kilowatt amplifier has a gain of 31.6 dB, my old DIY amp has 29.6 dB.
The Sony speakers are rated at 89 dB/W/m, the 15" driver at 96.6 dB/W/m (not sure about this but sounds reasonable).
The bass amplifier is the limiting factor because it has only ~50W power. This will give 101.6 dB SPL at my listening position 4 meters away.
The Sony boomboxes need to be powered with 145W each to archieve the same 101.6 dB SPL.
This is 290W vs. 50W for the same loudness.
At the moment I use a -6 dB pad for the bass amp to match gain / sensitivity.
This sounds right to me. Maybe I will adjust it later.
This is one of the things I enjoyed - no deadline.
However, you can count on my support.
The last thing missing is a housing. First I wanted to have the interior complete and working. I have a concept already but I'm far from having usable drawings.
I enjoy great sound at the moment but I think this is not affected by the amplifier in any way. I believe amplifiers are actually inaudible. This is something one could debate about endlessly.
I fixed my old crappy DIY active crossover and this improved the sound remarkably since I can use the 15" bass speaker again. I hate the bass from my cheap Sony speakers. I love bass and need kick instead of undefined boomy "whooomphhh".
Doing the calculations to match amplifiers and speaker sensitivity showed what such a high powered amplifier is good for: Driving inefficient loudspeakers. Want more dB? Get more efficient speakers!
A little calculation (I hope I did it right, please correct me if I'm wrong):
The Kilowatt amplifier has a gain of 31.6 dB, my old DIY amp has 29.6 dB.
The Sony speakers are rated at 89 dB/W/m, the 15" driver at 96.6 dB/W/m (not sure about this but sounds reasonable).
The bass amplifier is the limiting factor because it has only ~50W power. This will give 101.6 dB SPL at my listening position 4 meters away.
The Sony boomboxes need to be powered with 145W each to archieve the same 101.6 dB SPL.
This is 290W vs. 50W for the same loudness.
At the moment I use a -6 dB pad for the bass amp to match gain / sensitivity.
This sounds right to me. Maybe I will adjust it later.
Attachments
Hmmmmmmm............. nice monster ... Lee knatta Congratulations...........!!!!!!!!!!
look at that capacitor complex!!!!!!!!!!!!!!!!!!!! damn!!!!!!!! that's Killer one!!!!!!!!!!!!!!!
And could you write your reviews on the amp? how was the sound quality, spl, what speakers you use/d to listen.
Do you use the amp for lfe channel or full range?
look at that capacitor complex!!!!!!!!!!!!!!!!!!!! damn!!!!!!!! that's Killer one!!!!!!!!!!!!!!!
And could you write your reviews on the amp? how was the sound quality, spl, what speakers you use/d to listen.
Do you use the amp for lfe channel or full range?
Khatta hi lee
I want to make this amp
Can you send me the original schematic employee
* send along with measurements
to help me in this regard
Hi Andrew
I didn't know there are different amps called AV1000.
I'm building the one from Aussie Amlifiers.
I downloaded schematics from DIY Amplifier - Audio Amplifier Modules - MOSFET Amps - Audio Electronics - Power Amps long time ago.
I have three schematics to work with:
AV800 updated 2001-02-22
AV800 updated 2004-03-02
AV1000 from 2002-01-25
Lee
hi lee could you post that schematics? im looking for
tnks a lot
Hi Karl,
Sorry I missed your post. Somehow the notification did not reach me.
The smaller PCB is for the rectifier.
You should find the schematic in earlier posts already.
But I spotted some mistakes in the meantime and made some adjustments to components in the schematic.
This affects the inverting input. With the current resistor values CMMR is poor. With new values in theory up to -40dB could be reached but I expect much lower CMMR due to component temperature drift.
By the way: If you're serious about building this amp I would recommend to use a lower supply voltage. 90V is too close to the SOA. 70 to 80 Volt is plenty and gives more robustness.
Please find attached the latest schematic.
Regarding PCBs:
Please understand that I won't publish manufacturing data.
But you can have PCBs if you like. Contact me for an offer.
Hi, thanks for the input.
I´m interested in offers for the pcb´s. How can I send you my email adress privately?
About SOA I´m a little surprised - there are posts, that the amp should work well, also with +/- 105 V DC. The fets should not be critical, by exceeding maximum specified voltage.
Could your SOA consideration be compensated with bigger number of output fets?
Kind regards
Karl
I´m interested in offers for the pcb´s. How can I send you my email adress privately?
About SOA I´m a little surprised - there are posts, that the amp should work well, also with +/- 105 V DC. The fets should not be critical, by exceeding maximum specified voltage.
Could your SOA consideration be compensated with bigger number of output fets?
Kind regards
Karl
Hi Karl,
just send me a PM with your mail address.
I had a very brilliant colleague in my previous company and he had a look at the schematic and pointed out some potential issues like the SOA.
As far as I remember I was able to follow this.
The SOA for the IRFP240 at 25°C looks good:
But thermal de-rating needs to be considered as well:
With thermal de-rating the SOA at 100°C maybe roughly can be halved and there it gets critical.
I'm not sure whether this can be solved with more output transistors. There become harder to drive and quiescent current gets extreme.
My amp makes a good heater with roughly 250W dissipation idle anyway. You need to get rid of the heat.
Anyway, the amp is still working for years now but I never leave class A.
I have not electrocuted myself yet but may have a hearing damage already.
just send me a PM with your mail address.
I had a very brilliant colleague in my previous company and he had a look at the schematic and pointed out some potential issues like the SOA.
As far as I remember I was able to follow this.
The SOA for the IRFP240 at 25°C looks good:
But thermal de-rating needs to be considered as well:
With thermal de-rating the SOA at 100°C maybe roughly can be halved and there it gets critical.
I'm not sure whether this can be solved with more output transistors. There become harder to drive and quiescent current gets extreme.
My amp makes a good heater with roughly 250W dissipation idle anyway. You need to get rid of the heat.
Anyway, the amp is still working for years now but I never leave class A.
I have not electrocuted myself yet but may have a hearing damage already.
Attachments
Hi Lee,
sorry to come back with long delay. Thank´s for the explanation.
Did you measure the difference of the bias currrents of the single Fet´s. I measured 12,2- 18,2mV athe IRFP 9240 source resistors and 11-12,2 mV at the IRFP240 source resistors with 0,22Ohms each. THe Fet´s had been matched from 3,64-3,65volts and 4,03-4,04 volts.
thank you for any input
kind regards
Karl
sorry to come back with long delay. Thank´s for the explanation.
Did you measure the difference of the bias currrents of the single Fet´s. I measured 12,2- 18,2mV athe IRFP 9240 source resistors and 11-12,2 mV at the IRFP240 source resistors with 0,22Ohms each. THe Fet´s had been matched from 3,64-3,65volts and 4,03-4,04 volts.
thank you for any input
kind regards
Karl
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.