Hi everyone,
Well I am certainly not the first to surface a new X ALEPH on the forum but I feel all should be shared.
At last the parts arrived (transformers), so carefully everthying was checked and re checked, On goes the switch oowee no smoke.
Technically all has been said in other threads, this one has 13.4 Dcv on the rails using the original shematics with 2 pairs of IRF240's a side, the bias reads about 0.5 volts across the 0.22 ohms resisters, hot enough says I with a wink.
I have a few milli volts of offset and less then 200mill volts absolute offsett....I mean who cares...it seem to be erroding with warm up like Mr Pass says..
Okay. The lounge rooms looks like a mad scientist's picnic but wow!!Having dragged a bunch of wires, castings and big R/S into the listening domain it looks like CPO3 mixed up.
Using the recently modified X BOSOZ, the sound would appear be from the works of Mr Pass in the AX Pdf. There is no point beating around the bush, its that good.
The baby X Aleph had no problems at all man handling the Greg Timbers (JBL legend) 4345 JBL design with easy. The bass was a real surprise, it rendered space and timbre with accute accuracy and power. The vocals appear to be more visable to the eye and ear and all is revealed in the mix. The Micro dynamic resolve and instrumental clarity is spine tingling via the super 10 inch 2122 mid cone.
I find this quite exciting, at last an amp (a system) that allows you to view the portrait as is....... face on the canvas.
And I can see the peanut butter & chocolate from here.
Where do I go from here...my oh my.
Thankyou everyone for this forum and especially Mr Pass.
regards
Ian
Well I am certainly not the first to surface a new X ALEPH on the forum but I feel all should be shared.
At last the parts arrived (transformers), so carefully everthying was checked and re checked, On goes the switch oowee no smoke.
Technically all has been said in other threads, this one has 13.4 Dcv on the rails using the original shematics with 2 pairs of IRF240's a side, the bias reads about 0.5 volts across the 0.22 ohms resisters, hot enough says I with a wink.
I have a few milli volts of offset and less then 200mill volts absolute offsett....I mean who cares...it seem to be erroding with warm up like Mr Pass says..
Okay. The lounge rooms looks like a mad scientist's picnic but wow!!Having dragged a bunch of wires, castings and big R/S into the listening domain it looks like CPO3 mixed up.
Using the recently modified X BOSOZ, the sound would appear be from the works of Mr Pass in the AX Pdf. There is no point beating around the bush, its that good.
The baby X Aleph had no problems at all man handling the Greg Timbers (JBL legend) 4345 JBL design with easy. The bass was a real surprise, it rendered space and timbre with accute accuracy and power. The vocals appear to be more visable to the eye and ear and all is revealed in the mix. The Micro dynamic resolve and instrumental clarity is spine tingling via the super 10 inch 2122 mid cone.
I find this quite exciting, at last an amp (a system) that allows you to view the portrait as is....... face on the canvas.
And I can see the peanut butter & chocolate from here.
Where do I go from here...my oh my.
Thankyou everyone for this forum and especially Mr Pass.
regards
Ian
Hey you lot,
Give me a go........I'm still listening..James Morrison at the moment.....stuff the current share for the moment..........I don't care right now.....zonk. Just eat my ears bab.
Let me show you soon....the new woman in my life.....she will just blow you away...really!!! Trust me....Muhhahahahaha
We're just getting to know each other on first name basis.
So cool it ....you lot.
Ian
Give me a go........I'm still listening..James Morrison at the moment.....stuff the current share for the moment..........I don't care right now.....zonk. Just eat my ears bab.
Let me show you soon....the new woman in my life.....she will just blow you away...really!!! Trust me....Muhhahahahaha
We're just getting to know each other on first name basis.
So cool it ....you lot.
Ian
Hi Edwin,
Correct,
The absolute offset would appear to be declining, about 200mv in full fight. I'll look at the current share tomorrow.
Mind you I have not seriously tweeked anything. Just balanced her and a quick null on the central diff pair..... I'm more concerned about 30 watts per device, but I trust IRF @ 60 C.
Andrea...The Corrs on at the moment...getting physical.
The X Aleph appears to have uncanny spead of sound stage and limitless depth. Ouch she just pinched my bum.
Ian
Correct,
The absolute offset would appear to be declining, about 200mv in full fight. I'll look at the current share tomorrow.
Mind you I have not seriously tweeked anything. Just balanced her and a quick null on the central diff pair..... I'm more concerned about 30 watts per device, but I trust IRF @ 60 C.
Andrea...The Corrs on at the moment...getting physical.
The X Aleph appears to have uncanny spead of sound stage and limitless depth. Ouch she just pinched my bum.
Ian
Some subjective view before the neighbours crack it,
The A Aleph appears to hightlight tranisents very well,
Any percussive sounds...Caroline's drum kit...its so real you can fell the snap of the snare, the crack of the kick.... its in the room surrrrrrrrrrrreal.
And Where are those 18 inch woofers.........they disppeared...the distinction between felt and heard bass is like a tremor and shock wave.
The the harder I push the better she performs without effort.
Ian
'
Heres a snippet of the board in progress...this is all John Inlow's handy work.
The A Aleph appears to hightlight tranisents very well,
Any percussive sounds...Caroline's drum kit...its so real you can fell the snap of the snare, the crack of the kick.... its in the room surrrrrrrrrrrreal.
And Where are those 18 inch woofers.........they disppeared...the distinction between felt and heard bass is like a tremor and shock wave.
The the harder I push the better she performs without effort.
Ian
'Heres a snippet of the board in progress...this is all John Inlow's handy work.
Attachments
Well,
Thanks for your response and sharing.
Enjoy...........and thanks Greg Timbers for the delivery...
Greg Timbers was kind enough to provide detailed technical information and guidance on the tuning of my JBL 4345 heritage project. This is a stunning speaker system.... a masterpiece acoustic engineering.
Ian
Greg Timbers - Chief Development Engineer for Harman Consumer
Thanks for your response and sharing.
Enjoy...........and thanks Greg Timbers for the delivery...
Greg Timbers was kind enough to provide detailed technical information and guidance on the tuning of my JBL 4345 heritage project. This is a stunning speaker system.... a masterpiece acoustic engineering.
Ian
Greg Timbers - Chief Development Engineer for Harman Consumer
Attachments
They look fantastic.
What's the point of using these ridiculously low rails and insanely high currents to get a few dirty watts, as it turns out by actual measurements? Double THD when going from 12 to 15 v rails, as I recall.
-Do you have speakers with 1 ohm impedance that you need to circulate 10 amps per channel?
-Do you plan to double your amp for use as an arc welding station?
For the power you are going to be able to get out this circuit you can, even by very conservative standards, use one mosfet per side, it cuts down on the mosfet capacitance, if you want to get even fancier you can use a high transconductance mosftet like the 044 that should sound better ( in principle).
I had the same criticism for the x-zenlight with 12v rails. The high currents put a much higher demand on the PS in terms of handling the ripple, heating on the rectifiers, transformer impedance and on and on and on.
free your mind
Yeah, but you're still completely wrong on that one! The high currents needed are for even a 6 ohm load without current limiting... which most 8 ohm speaker get down to.
Simulate it or build it and see for yourself!
Free YOUR mind.
The aleph sources in the X make a big difference. I am actually planning on using 1 device/side in my AlephX, because of everything you mentioned. No need for more. If I were going to be using these with my 4 ohm MTMs, however, I would up the current to be on the safe side. Why limit the output capability when you have the voltage headroom (especially when you are talking about a low powered amp... it would be different if you had a clean 100 watts into 8 or 4 ohms). It all depends on your speakers.
Steve
macka said:Some subjective view before the neighbours crack it,
The A Aleph appears to hightlight tranisents very well,
Any percussive sounds...Caroline's drum kit...its so real you can fell the snap of the snare, the crack of the kick.... its in the room surrrrrrrrrrrreal.
And Where are those 18 inch woofers.........they disppeared...the distinction between felt and heard bass is like a tremor and shock wave.
The the harder I push the better she performs without effort.
Ian
Hey macka , what a view!
The thing that more of all impressed me is the complete coherence of the musical articulation: I play(back) the accordion on some of my favourite titles and it seems to be there together with the players in the room
....
but I'm for more voltage rails than +-15v.
nobody special said:
Yeah, but you're still completely wrong on that one! The high currents needed are for even a 6 ohm load without current limiting... which most 8 ohm speaker get down to.
Simulate it or build it and see for yourself!
Free YOUR mind.
The aleph sources in the X make a big difference. I am actually planning on using 1 device/side in my AlephX, because of everything you mentioned. No need for more. If I were going to be using these with my 4 ohm MTMs, however, I would up the current to be on the safe side. Why limit the output capability when you have the voltage headroom (especially when you are talking about a low powered amp... it would be different if you had a clean 100 watts into 8 or 4 ohms). It all depends on your speakers.
Steve
Dude, do you really need 10 amps at 13v to get 20 tiny watts? I don't want to get into another argument about sims vs actual circuit but to put it in prospective, Nelson biases his xa200 at 8 amps with 30volts rails.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.