Thanks xrk. Literally right under my nose! I think I will stick with the standard board as I may be able to find the support I need.
I thought I would have a go at etching my first boards - far from perfect 🙂 Thanks for the files Phunk! I have some pcb drill bits arriving tomorrow so I should be able to finish them off.
For rev.3 is the attached parts list the most up to date and compatible with Phunks layout?
Many thanks
Richard
Attachments
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Nice work and looks great even for a first board. What a coincidence I just etched my first board too - a simple hand drawn layout using nail polish. Those drill bits break really easy so be sure to get extras.
Here is my very first home etched board - a single ended classs A head amp.
What did you use for the iron on transfer or did you use photo resist?
Thanks. Your head amp looks tiny! Which one did you build - do you have link? I may try and build Juma's head amp
I printed on the shiny backing paper of a sheet of Avery labels. I found it much quicker and it didn't require so much heat. It also peels off without having to soak in water.
I printed on the shiny backing paper of a sheet of Avery labels. I found it much quicker and it didn't require so much heat. It also peels off without having to soak in water.
Sticker backing paper is a good idea. I always thought that was too waxy to work.
Here is link to amp. It's a real class A with lots of excess heat like a speaker amp. Probably can power speakers.
http://www.diyaudio.com/forums/headphone-systems/95841-mosfet-follower-headphone-amplifier-6.html
I don't know if LU1014 have to220 packageNice work and looks great even for a first board. What a coincidence I just etched my first board too - a simple hand drawn layout using nail polish. Those drill bits break really easy so be sure to get extras.
Here is my very first home etched board - a single ended classs A head amp.
What did you use for the iron on transfer or did you use photo resist?
That's me fooling around with IRF610 (won't work) while waiting for LU1014 to arrive. It sure would make mounting an LU1014 easier if it were TO-220. I was thinking of soldering one into an old TO-220 copper tab from a dead transistor. Then you could mount it like a TO-220.
😀
Different species. LU1014 Power Jfet , IRF610 Mosfet .
I mounted mine using small alu bar.
Nicely home etched pcb's Tripmaster.I'm still waiting on my pcb's(should get it in +-2 to 3 weeks).You will be the first person I know of with that particular layout.
Keep us informed with your build.I can't wait to start building(parts are also arriving more or less the same time).
Regarding the "Big Quasi"-I have started with a layout,but am waiting on final component values & parts count as Hugh mentioned that the "Big Quasi" is not totally refined yet,but the current circuit should work ok.
I am also busy with a MLTL to partner the amp.It will have 2x4" 4ohm drivers in series per box (Pioneer dual cone car speakers).Trying to set up as Fullrange but might add a tweeter.Am busy deriving the TS parameters from the speaker because I can't seem to find any parameters online The dual cone Pioneers are quite cheap over here(+-12 USD per pair).Trying to keep to the Quasi motto of "low cost but effective".
Regards
phunk
Keep us informed with your build.I can't wait to start building(parts are also arriving more or less the same time).
Regarding the "Big Quasi"-I have started with a layout,but am waiting on final component values & parts count as Hugh mentioned that the "Big Quasi" is not totally refined yet,but the current circuit should work ok.
I am also busy with a MLTL to partner the amp.It will have 2x4" 4ohm drivers in series per box (Pioneer dual cone car speakers).Trying to set up as Fullrange but might add a tweeter.Am busy deriving the TS parameters from the speaker because I can't seem to find any parameters online The dual cone Pioneers are quite cheap over here(+-12 USD per pair).Trying to keep to the Quasi motto of "low cost but effective".
Regards
phunk
Hi phunk,
you don't will find TSP for car speaker.
TL is good.
Perhaps you would like this: K&T Cheap Tricks- any good constructed speakers.
Strassacker, Komponenten: Lautsprecher, Frequenzweichen, Bauelemente
CT 273 and CT 225- wich i use with Quasi- and a real good pair- not deep but clean with
dynamic- you could try it.
If not like it is a start for Mini PA System.
I have run a order Dasz boards- are shipped.
Regards.
you don't will find TSP for car speaker.
TL is good.
Perhaps you would like this: K&T Cheap Tricks- any good constructed speakers.
Strassacker, Komponenten: Lautsprecher, Frequenzweichen, Bauelemente
CT 273 and CT 225- wich i use with Quasi- and a real good pair- not deep but clean with
dynamic- you could try it.
If not like it is a start for Mini PA System.
I have run a order Dasz boards- are shipped.
Regards.
Thanks for the link Bangla H.Some nice looking diy speakers there,just a bit out of my price range.
I think I'll stick to trying small(4 to 5 inch car speakers),its much cheaper.I am busy setting up a computer just for audio work.I have a couple of cheap SoundBlaster Live 5.1 sound cards with asio support up till Windows 8(haven't tried it Win 10,but should work if it runs on Win8).Got different software and plugins with test tone generators and such.I did a bit of playing with DAW's(Digital Audio Workstations)and know the ins&outs of the software.I love to teach myself new stuff as I'm always inquisitive especially when it pertains to sound and audio.Yeah,the audio bug bit early,I had
my first stereo amplifier(Pioneer) when I was 15.Got it from a "client" whose Nad amp I fixed(had to order the service manual from Nad in those days).Recapped and upgraded a couple of components on the Pioneer.I still remember the psu cap upgrade brought the best sonic improvement to my ears with the type of music I was listening to at that young age.
I had a copy of "Loudspeaker Design Cookbook" which I got in 1985(it was subsequently stolen. +-10 years later from a friends vehicle when his car was broken into).At that time there weren't a lot of TS parameters available for most speakers,so had to go the manual way of getting the info via "Cookbbok".Now its much easier with everything basically just a click away on the internet(procedure wise).
I love anything with a steep learning curve because of the satisfaction you feel once you start mastering the specific subject matter.
So for now its "back to the drawing board" and building jigs.
Regards
phunk
I think I'll stick to trying small(4 to 5 inch car speakers),its much cheaper.I am busy setting up a computer just for audio work.I have a couple of cheap SoundBlaster Live 5.1 sound cards with asio support up till Windows 8(haven't tried it Win 10,but should work if it runs on Win8).Got different software and plugins with test tone generators and such.I did a bit of playing with DAW's(Digital Audio Workstations)and know the ins&outs of the software.I love to teach myself new stuff as I'm always inquisitive especially when it pertains to sound and audio.Yeah,the audio bug bit early,I had
my first stereo amplifier(Pioneer) when I was 15.Got it from a "client" whose Nad amp I fixed(had to order the service manual from Nad in those days).Recapped and upgraded a couple of components on the Pioneer.I still remember the psu cap upgrade brought the best sonic improvement to my ears with the type of music I was listening to at that young age.
I had a copy of "Loudspeaker Design Cookbook" which I got in 1985(it was subsequently stolen. +-10 years later from a friends vehicle when his car was broken into).At that time there weren't a lot of TS parameters available for most speakers,so had to go the manual way of getting the info via "Cookbbok".Now its much easier with everything basically just a click away on the internet(procedure wise).
I love anything with a steep learning curve because of the satisfaction you feel once you start mastering the specific subject matter.
So for now its "back to the drawing board" and building jigs.
Regards
phunk
Hello. I have 2 IRFP260N (genuine) and 2 IRF250N bought from Tayda Electronics and i dont know whether they are fake or not. Can IRFP260N be used in this amp or there will be stability issues or worse sound?
Any substitutions for phase inverter transistor as i only have 2 KSA1381 and i m gonna use them for VAS stage.
Any substitutions for phase inverter transistor as i only have 2 KSA1381 and i m gonna use them for VAS stage.
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special offer Blue Start TQWT phunk
Hi, phunk
yes agree- its always a challenge to learn and test for own experience- have
read with interest your post.
Here is unbeatable speaker: 😀 you have all you like.
Lautsprecher Shop | Blue Start 5 TQWT Lautsprecher Bausatz | Lautsprecher Selbstbau
This are real German Products! manufactured in Neu Ulm- ETON
The Tweeter has a excellent radiating in angel 15/30/60° to 20kHz.
Before you frickeling on something with questionably result.......🙄
There are two other cabinets- closed and vented.
Contact Mr. Bauer in Frankfurt, a very engaged Engineer.
Hi, phunk
yes agree- its always a challenge to learn and test for own experience- have
read with interest your post.
Here is unbeatable speaker: 😀 you have all you like.
Lautsprecher Shop | Blue Start 5 TQWT Lautsprecher Bausatz | Lautsprecher Selbstbau
This are real German Products! manufactured in Neu Ulm- ETON
The Tweeter has a excellent radiating in angel 15/30/60° to 20kHz.
Before you frickeling on something with questionably result.......🙄
There are two other cabinets- closed and vented.
Contact Mr. Bauer in Frankfurt, a very engaged Engineer.
here is the closed
Lautsprecher Shop | Blue Start 5 CB Bausatz | Lautsprecher Selbstbau
and that one i have to finish since two years now:
Lautsprecher Shop | CerAl 3.2 Bausatz | Lautsprecher Selbstbau
so the race goes on.......wrrroommm!
Lautsprecher Shop | Blue Start 5 CB Bausatz | Lautsprecher Selbstbau
and that one i have to finish since two years now:
Lautsprecher Shop | CerAl 3.2 Bausatz | Lautsprecher Selbstbau
so the race goes on.......wrrroommm!
My other thought would be 2SA1387,HSB649A.
And what about upper mosfet? genuine IRF260N or IRF250N from Tayda electronics?
I attach my progress.
Attachments
mushroom pcb's
That 3rd picture, is that some kind of flower power option in your CAD program and if so what's the name of the program, nonetheless beautiful. 🙂
maouna,
build in the 250- i don't see- to fake posts- a reason- here i bought too, some with showed IOR logo by German distributor.
If nothing smoked or smelt measuring for testing from Gate Q6 to Base Q5(r11, r10, d7)point.
There should be ~ 5,2V- MosFet stays <ON<.
Next Amp should sing before Christmas !
build in the 250- i don't see- to fake posts- a reason- here i bought too, some with showed IOR logo by German distributor.
If nothing smoked or smelt measuring for testing from Gate Q6 to Base Q5(r11, r10, d7)point.
There should be ~ 5,2V- MosFet stays <ON<.
Next Amp should sing before Christmas !
It occurs that if you use a larger output device you could increase the rails to around 56V - and still use a SINGLE pair.
The mosfet would be a 512-FQA40N25 (Mouser) TO3-P, 40A, 280W, 250V ($USD3.28)
The npn would be 863-MJL4281AG (Mouser) TO264, 15A, 230W, 350V ($USD5.94).
With stiff rails at 56V, you would reach 100Vpp ouput into 8R, which is 156W. A great amplifier, the same pcb layouts, and a lot of output power at very high sound quality.
Hugh
The mosfet would be a 512-FQA40N25 (Mouser) TO3-P, 40A, 280W, 250V ($USD3.28)
The npn would be 863-MJL4281AG (Mouser) TO264, 15A, 230W, 350V ($USD5.94).
With stiff rails at 56V, you would reach 100Vpp ouput into 8R, which is 156W. A great amplifier, the same pcb layouts, and a lot of output power at very high sound quality.
Hugh
What about the small and VAS transistors. Seemed like Q3 got quite hot at +-50V rails.
That would be cool with flag heatsinks on Q3 and the inverter, using 2SA1381.
The current through Q1 and Q2 would not be different; it's set by fixed resistors on the circuit, while dissipation through Q3 would be increased quite a bit from 56V over 42V; but still within flag heatsinks (<24C per watt). The outputs would be dissipating around 125mA x 55V, around 6.9W apiece. This would need a substantial heatsink for the output devices, however, just as you suggest.
But it's doable, and I cannot see any reason why it would not sound almost the same but with almost double the power! Certainly an attractive exercise as we have lovely pcbs now from Prasi, Thiago and PHunk and with larger transformers it could be quite viable since so many people like the sound of this amp.
Cheers,
Hugh
The current through Q1 and Q2 would not be different; it's set by fixed resistors on the circuit, while dissipation through Q3 would be increased quite a bit from 56V over 42V; but still within flag heatsinks (<24C per watt). The outputs would be dissipating around 125mA x 55V, around 6.9W apiece. This would need a substantial heatsink for the output devices, however, just as you suggest.
But it's doable, and I cannot see any reason why it would not sound almost the same but with almost double the power! Certainly an attractive exercise as we have lovely pcbs now from Prasi, Thiago and PHunk and with larger transformers it could be quite viable since so many people like the sound of this amp.
Cheers,
Hugh