Aermacchi MB 339 .... one of the most famous 'training' aircrafts.
http://farm3.static.flickr.com/2617/3743576251_4a06681947.jpg
http://farm3.static.flickr.com/2617/3743576251_4a06681947.jpg
After years of reading online reviews on audio gears, I came to the conclusion that the term "fast" is one of the traits of audio Holy Grail.
speed + agility = even better (give me a mini-cooper over a Corvette any day of the week)
nice work, impressive
tho the black sardine tin can isn't
nice old Teak
I have never seen any teak that smooth
I'm working on a teak box right now
how did you polish it ?
Attachments
nice work, impressive
tho the black sardine tin can isn't
nice old Teak
I have never seen any teak that smooth
I'm working on a teak box right now
how did you polish it ?
thanks tinitus,
sardine tin ? don't know what you mean!
the teak was fairly smooth to start with, used carborundum paper from 320 to 1200grit then 0000 steel wool and finished with a few coats of teak oil.
(will find something better to replace ST).
simon
Sardine can.
An externally hosted image should be here but it was not working when we last tested it.
Posted elsewhere but I figured I'd put in an update here:
Board Top
Board Bottom
With Hammond OPTs
I've uploaded a picture I took today showing the amp with a pair of 8417 output tubes and Edcor GXPP transformers. I didn't dust it off. It works and has been at work for many years now.
Board Top
Board Bottom
With Hammond OPTs
I've uploaded a picture I took today showing the amp with a pair of 8417 output tubes and Edcor GXPP transformers. I didn't dust it off. It works and has been at work for many years now.
Attachments
My first amp project
Just finished my tubleab SSE after 6 months
http://www.diyaudio.com/forums/tubes-valves/71300-photo-gallery-358.html#post2662390
Just finished my tubleab SSE after 6 months
http://www.diyaudio.com/forums/tubes-valves/71300-photo-gallery-358.html#post2662390
My Compact SSE
I have finally finally finished my SSE.
I got the most excellent board in May 2007 and finished the initial builld in June 2009 but the top plate was mounted on a crude frame made from DIY store softwood. I have at last made a proper base from an old mahogany bed head cut into strips. It was in my Father in Law's stash for many years and since he died in 1999 it has been in mine awaiting a worthy use.
The PT is a Hammond 374BX and the OPTs are Electra Print 5k to 8ohm. The top plate was made by Schaeffer AG (AKA Front Panel Express).
I have finally finally finished my SSE.
I got the most excellent board in May 2007 and finished the initial builld in June 2009 but the top plate was mounted on a crude frame made from DIY store softwood. I have at last made a proper base from an old mahogany bed head cut into strips. It was in my Father in Law's stash for many years and since he died in 1999 it has been in mine awaiting a worthy use.
The PT is a Hammond 374BX and the OPTs are Electra Print 5k to 8ohm. The top plate was made by Schaeffer AG (AKA Front Panel Express).
Attachments
Why did I do that? Well...
I'll admit it may be an unusual aesthetic choice. I messed about for ages with different layouts. I wanted something compact - a friend of mine is a big fan of the QUAD II and that was an influence*. I ended up with the transformers in a row with the board in front and then the rest flowed from that. I was going to have the top machined anyway to mount the board and transformers - there was space - the incremental cost was minimal - it made sense to me. I will also point out that the mains wiring runs are minimised and there is nothing sticking out of the back if I want to place it on a shallow shelf.
* As was George's Industrial Strength SSE.
Too kind. Actually they started out as offcuts - as I cut the rebate first each miter was two cuts. In fact there were lots of cuts - I spent ages selecting the best pieces then ruined the best bit by cutting it to length dead on but not at 45deg...
but what is the power mains chassis plug doing on the top plate
I'll admit it may be an unusual aesthetic choice. I messed about for ages with different layouts. I wanted something compact - a friend of mine is a big fan of the QUAD II and that was an influence*. I ended up with the transformers in a row with the board in front and then the rest flowed from that. I was going to have the top machined anyway to mount the board and transformers - there was space - the incremental cost was minimal - it made sense to me. I will also point out that the mains wiring runs are minimised and there is nothing sticking out of the back if I want to place it on a shallow shelf.
* As was George's Industrial Strength SSE.
Too kind. Actually they started out as offcuts - as I cut the rebate first each miter was two cuts. In fact there were lots of cuts - I spent ages selecting the best pieces then ruined the best bit by cutting it to length dead on but not at 45deg...
Bye Bye Cinderella Castle
Some pages ago I posted the pictures of my Tubelab SE 300B that I called "Cinderella Castle" for the shape of the case.
These was perfectly fine, but it had separate PSU, a solution that is not the best, mostly if you have a child running around. Additionally my PSU relies on a power transformer that is 100 V main, and I'll move back to Europe soon, so I wanted to do something in a single chassis with a transformer with multi voltage primary.
I wanted to put all kind of fancy thing inside, regulated HV psi, regulators for the filament of the drivers, but I ended up with a very standard build.
I tried the HV PSU from diyhisupply. I think there is something in some transient that the mosfet generates that it does not like, as I managed to kill it twice, although I manage to make it work, I could not go further playing test tones.
For the filament regulators is maybe a complication that is not really worth it, although my transformer as a secondary for that.
Some suggestions (solutions I used also in the 45):
1) Install measuring point outside the chassis for the voltages that you need to measure for the trimming.
2) Use multi turn pots, they are easy to set.
3) Make holes in the top, so that you can trim the board with closed chassis. Use a plastic screw driver (just in case).
4) I installed a 50 ohm 0.5 W trimmer on the resistor that feeds the driver filament, just to be right on the spot.
I'll post some pictures of the inside. Beside the standard CLC (47uF-10H-100uF) I installed the 10 ohm resistors off board, between the measuring points, and two 100uF mylar capacitors, that make another RC filter.
I did not have time to do much measurements, but it sounds very quite.
I also tried the lower supply for the mosfet, but for some reason I did not manage to get it right. I am happy with the results, and it matches with the rest of the equipment.
Merry Christmas,
Davide
Some pages ago I posted the pictures of my Tubelab SE 300B that I called "Cinderella Castle" for the shape of the case.
These was perfectly fine, but it had separate PSU, a solution that is not the best, mostly if you have a child running around. Additionally my PSU relies on a power transformer that is 100 V main, and I'll move back to Europe soon, so I wanted to do something in a single chassis with a transformer with multi voltage primary.
I wanted to put all kind of fancy thing inside, regulated HV psi, regulators for the filament of the drivers, but I ended up with a very standard build.
I tried the HV PSU from diyhisupply. I think there is something in some transient that the mosfet generates that it does not like, as I managed to kill it twice, although I manage to make it work, I could not go further playing test tones.
For the filament regulators is maybe a complication that is not really worth it, although my transformer as a secondary for that.
Some suggestions (solutions I used also in the 45):
1) Install measuring point outside the chassis for the voltages that you need to measure for the trimming.
2) Use multi turn pots, they are easy to set.
3) Make holes in the top, so that you can trim the board with closed chassis. Use a plastic screw driver (just in case).
4) I installed a 50 ohm 0.5 W trimmer on the resistor that feeds the driver filament, just to be right on the spot.
I'll post some pictures of the inside. Beside the standard CLC (47uF-10H-100uF) I installed the 10 ohm resistors off board, between the measuring points, and two 100uF mylar capacitors, that make another RC filter.
I did not have time to do much measurements, but it sounds very quite.
I also tried the lower supply for the mosfet, but for some reason I did not manage to get it right. I am happy with the results, and it matches with the rest of the equipment.
Merry Christmas,
Davide
Attachments
I had time to do some measurements and listening today.
This build is absolutely silent. I could measure around 0.3 mV or ripple, not audible even with my hear on the woofer.
It sounds big, even paired with my Sonus Faber Grand Piano, that are not the best choice for a tube SE. It managed to shake the windows with Massive Attack. The Hasimoto OPTs do their job, I highly recommend them.
With 1V input I have 1% THD on right channel and 1.5% on left channel. I bet is one of the 5842. It is biased now at 75mA 400V. Mainly second harmonic.
The only thing I do not like, is a little buzz, hardly audible that is coming from the amp itself, it is somewhere in the board side. I am not concern about the noise, but I am wondering if it can be a bad joint. Or can it be a tube itself ? Is it normal ?
I'll post some pictures of under the hood soon.
Happy new Year,
Davide
This build is absolutely silent. I could measure around 0.3 mV or ripple, not audible even with my hear on the woofer.
It sounds big, even paired with my Sonus Faber Grand Piano, that are not the best choice for a tube SE. It managed to shake the windows with Massive Attack. The Hasimoto OPTs do their job, I highly recommend them.
With 1V input I have 1% THD on right channel and 1.5% on left channel. I bet is one of the 5842. It is biased now at 75mA 400V. Mainly second harmonic.
The only thing I do not like, is a little buzz, hardly audible that is coming from the amp itself, it is somewhere in the board side. I am not concern about the noise, but I am wondering if it can be a bad joint. Or can it be a tube itself ? Is it normal ?
I'll post some pictures of under the hood soon.
Happy new Year,
Davide
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