Air guitar Pre
- Thread starter sandford
- Start date
C
ced
Guest
Hey,
awesome how this thread has taken off and pleased those of you who've tried the air g love it.
However if graham has got the split rail to work dynamically then it is definitely the way forward and I would go with that. My only reservations when I tried it were dynamics which could easily have been down to raw psu considerations from the inferior one I cobbled together at the time. Will look forward to seeing your implementation graham.
cheers
Ced
awesome how this thread has taken off and pleased those of you who've tried the air g love it.
However if graham has got the split rail to work dynamically then it is definitely the way forward and I would go with that. My only reservations when I tried it were dynamics which could easily have been down to raw psu considerations from the inferior one I cobbled together at the time. Will look forward to seeing your implementation graham.
cheers
Ced
Hi Graham,
You did something like this then, on stripboard.
Dual railed gain stage looks like a very small thing.
Undoubtedly it will be a real nest of the spark!
Certainly we will need some input caps here to make it stable.
(This can be made much smaller in natural size as this one is wide to be clear)
I am too tired to double check this now..
What's the value for R3?
Oz
You did something like this then, on stripboard.
Dual railed gain stage looks like a very small thing.
Undoubtedly it will be a real nest of the spark!
Certainly we will need some input caps here to make it stable.
(This can be made much smaller in natural size as this one is wide to be clear)
I am too tired to double check this now..
What's the value for R3?
Oz
“The Bigest learning curve is 'The referance' you must have something to judge the last mod / tweek by.”
Graham,
Just for the record , what pre amp are you using now and is this your reference for
evaluating your designs . It would be useful to know what you are actually using as a yardstick
(I often hear you say a 52 beater or a 552 beater but I don’t think you use either of these
pre amps in your system)
Graham,
Just for the record , what pre amp are you using now and is this your reference for
evaluating your designs . It would be useful to know what you are actually using as a yardstick
(I often hear you say a 52 beater or a 552 beater but I don’t think you use either of these
pre amps in your system)
chrisallan
Go on - bodge it!
I'm all for upgrading the Air Guitar design to implement other features, but I'm worried that the group buy will get stuck again at the re-design stage and we dont seem to have anyone who has the time to do this.
I've sent a cad file off to PCB Train to see if they can use this to reduce costs, if anyone wants a copy of the dxf file to play with, let me know.
I've sent a cad file off to PCB Train to see if they can use this to reduce costs, if anyone wants a copy of the dxf file to play with, let me know.
laverda
pfm Member
Linnik said:Hi Graham,
You did something like this then, on stripboard.
Dual railed gain stage looks like a very small thing.
Undoubtedly it will be a real nest of the spark!
Certainly we will need some input caps here to make it stable.
(This can be made much smaller in natural size as this one is wide to be clear)
I am too tired to double check this now..
What's the value for R3?
Oz
That looks something like it Oz but the 1k feedback resistor needs to be 2k and the 10uf tants needs to be PPS in our opinion.
We use No caps across the power rails when sregs are used and these are a min requirement.
Graham
Anderzander
Grateful Bodger
chrisallan said:
Chris
Graham said he would post a pdf of his circuit. I think it's worth waiting for:
laverda said:
Stephen
chrisallan
Go on - bodge it!
Could the CAD file be posted as well? That's the bit I need as a dxf file can be imported into pcb software.Anderzander said:
chrisallan
Go on - bodge it!
A pcb type file might be even better, what file endings does it produce?laverda said:
Graham,
Do you mean like Evox SMR?
http://www.evox-rifa.com/europe/cmk_obsolete.htm
Otherwise it seems the available values are quite low.
http://www.jt-capacitor.com.tw/pps.htm
The stripboard photo is revised.
1 K resistor for 2 K (R4F), okay but which value is R3??
Graham, please check that SIGNAL OUT point.
Is it correct that way? I mean, the 10 uF cap is
not really a coupling cap there now.
Should it be from the upmost strip?
Which type of transistors have you used?
Well, I am not an expert here but this seems to have very rare 0V outlets..
Will this affect the signal path?? Is the +/- assembly making the 0V
paths so much less important?
Oz
Do you mean like Evox SMR?
http://www.evox-rifa.com/europe/cmk_obsolete.htm
Otherwise it seems the available values are quite low.
http://www.jt-capacitor.com.tw/pps.htm
The stripboard photo is revised.
1 K resistor for 2 K (R4F), okay but which value is R3??
Graham, please check that SIGNAL OUT point.
Is it correct that way? I mean, the 10 uF cap is
not really a coupling cap there now.
Should it be from the upmost strip?
Which type of transistors have you used?
Well, I am not an expert here but this seems to have very rare 0V outlets..
Will this affect the signal path?? Is the +/- assembly making the 0V
paths so much less important?
Oz
laverda
pfm Member
Linnik said:
Oz
Yes the Evox SMR are the ones........as used in the Air Guitar....
Other quiries answered later if I may....
Q. Is the +/- assembly making the 0V paths so much less important?
No, these 0v returns are very important Oz, as you and many others have found out............I/we built a few versions of this pre and 0v returns are very important. (attension to detail here pays off) and of course the Mr Tibbs
The Transistors are ZTX214c 1 off and ZTX348c 4 off robbed from old Naim boards, these are very good tranies indeed and sound Naimie?? We like the Naim sound, so tried to use what they might have used, I'm not saying that everything they do should be set in stone but they have been doing it for a long and are still using these ZTX tranies (they must have a shed load still)
More to come
Graham
laverda
pfm Member
S-Man said:
Sorry, S-man, I'm not the one who can answer these questions, (I'm as thick as shit) I just build and listen......If its better I keep it, if not, it goes in the bin.
You seem to have the 'know how' with how these things work.......I'm always willing to give a new idea a try......I dont analize (thats for the Gods) they do that very well here. I thank them one and all.
Graham