nielsk
Well-known member
any info on price and availability for the 2 channel version?
drip V72 pcb
- Thread starter dripelectronics
- Start date
Help Support GroupDIY Audio Forum:
dripelectronics
Well-known member
http://lomayesva.com/v72_pcb_manual.pdf
heres the manual
g.
bradb
Well-known member
Incredible and beautiful.
Browsing thru, looks like there are a lot of decisions to be made with regards to filtering, etc. Very very cool.
Browsing thru, looks like there are a lot of decisions to be made with regards to filtering, etc. Very very cool.
helterbelter
Well-known member
.............................................
speechless ! :shock:
speechless ! :shock:
A question on the power supply section...
I probably should have held out for the stereo version, but bought 2 mono V72 boards and intend to put into one chassis.
What, if any portions of the power supply could be shared across the 2 mono PCBs? Line transformer? Filter section? Suggestions to a somewhat noob welcomed.
thanks,
--Peter
I probably should have held out for the stereo version, but bought 2 mono V72 boards and intend to put into one chassis.
What, if any portions of the power supply could be shared across the 2 mono PCBs? Line transformer? Filter section? Suggestions to a somewhat noob welcomed.
thanks,
--Peter
dripelectronics
Well-known member
thanks! ill try to keep revising it in the coming weeks.
as for rigging two pcb together .,
ill need to write a small document on it .
the dual will not have atoms ,
to some people it matters and to others it doesn't .
the mono is a very high performance design .
atoms included.
so there are some trad offs .
more info to come on the dual version in the coming weeks .
g.
as for rigging two pcb together .,
ill need to write a small document on it .
the dual will not have atoms ,
to some people it matters and to others it doesn't .
the mono is a very high performance design .
atoms included.
so there are some trad offs .
more info to come on the dual version in the coming weeks .
g.
hitchhiker
Well-known member
so Good! I'm so up for the mono, ooooh baby! yeah! :thumb:
Neil
Well-known member
Wow! I'm sure I'm not alone when I say it's almost as much fun reading your manuals as it is actually building the darn equipment Greg!! What a work of art!! :thumb: :thumb: :thumb:
So you're saying there's a trade off in sound on the dual version? As in the dual one is a less "high performance design"? Can you elaborate a little bit? That may switch me to doing a couple of monos then.
Neil
So you're saying there's a trade off in sound on the dual version? As in the dual one is a less "high performance design"? Can you elaborate a little bit? That may switch me to doing a couple of monos then.
Neil
bradb
Well-known member
Hmmm...
Lots to think about here.
Is the V72 necessarily a "Hi-Fi" design?
What's the difference between the Lundahl and Sowter Chokes soundwise... forgive me if I missed it.
Lots to think about here.
Is the V72 necessarily a "Hi-Fi" design?
What's the difference between the Lundahl and Sowter Chokes soundwise... forgive me if I missed it.
zachs
Well-known member
Just got my boards holy smoke these things are beautiful! And thick!
Gotta start buying the rest of my parts now.
Gotta start buying the rest of my parts now.
bradb
Well-known member
Greg,
Sorry to pester you, I know you must be busy.
I'm gonna list some questions here.
1. What kind of transformer would you recommend for the DI input (turns ratio, electrical specs, etc)
2. When will the +48V supplemental boards be ready (rough time frame is fine)?
Thank you! I'm really excited
Sorry to pester you, I know you must be busy.
I'm gonna list some questions here.
1. What kind of transformer would you recommend for the DI input (turns ratio, electrical specs, etc)
2. When will the +48V supplemental boards be ready (rough time frame is fine)?
Thank you! I'm really excited
Grooveteer
Well-known member
Got the PCB yesterday. Beautiful! (it even smells good )
Thanks Greg!
)Thanks Greg!
dripelectronics
Well-known member
great !
i do love the look of the actual traces on the pcb ,
as for the di transformer , ill give a call to my lundahal rep here in the us .
there are a couple of options of a direct type box inside the case that feeds the xlr's
or to bypass the input transformer directly to the amp section .
the by pass is what im using now on this test unit here . sounds great .
jensen is know for their di transformers . ill give an order for one in the next few days .
im ording all the parts for a test phantom unit , to test out .
the time frame is a couple of weeks .
as for 'hi-fi'
the circuit is the circuit of the v72 .
the parts chosen for this project are intended to
be the highest available .
the electrolytics alone are off the chain .
and the actual circuit layout is my best yet .
i prototyped a pcb for both the lundahls and the sowters ,
the lundahl worked with out a problem and have a great tone to them .
the sowters pcb mount versions did not have a mu metal case ,
which is very important , and immediately began to pick up noise and hum .
but stopped when a mu metal case was put over them ,
they do have a non pcb mount version (mumetal case) , that can be connected to the pcb ,
but i will probably re-design a whole new board to work with them .
custom mu metal shields would have cost me 6 to 8 thousand .
so i had to hold off on that at the moment .
i avoided an essay in the manual as to avoid Rhetoric
due to the nature of the myth and legend of executing such
a debated topic as the v72 .
best,.
g.
i do love the look of the actual traces on the pcb ,
as for the di transformer , ill give a call to my lundahal rep here in the us .
there are a couple of options of a direct type box inside the case that feeds the xlr's
or to bypass the input transformer directly to the amp section .
the by pass is what im using now on this test unit here . sounds great .
jensen is know for their di transformers . ill give an order for one in the next few days .
im ording all the parts for a test phantom unit , to test out .
the time frame is a couple of weeks .
as for 'hi-fi'
the circuit is the circuit of the v72 .
the parts chosen for this project are intended to
be the highest available .
the electrolytics alone are off the chain .
and the actual circuit layout is my best yet .
i prototyped a pcb for both the lundahls and the sowters ,
the lundahl worked with out a problem and have a great tone to them .
the sowters pcb mount versions did not have a mu metal case ,
which is very important , and immediately began to pick up noise and hum .
but stopped when a mu metal case was put over them ,
they do have a non pcb mount version (mumetal case) , that can be connected to the pcb ,
but i will probably re-design a whole new board to work with them .
custom mu metal shields would have cost me 6 to 8 thousand .
so i had to hold off on that at the moment .
i avoided an essay in the manual as to avoid Rhetoric
due to the nature of the myth and legend of executing such
a debated topic as the v72 .
best,.
g.
Great work on the manual Greg!
On the DI input: couldn't you just implement the same method as Jakob used in is G9?
Using a switched TS socket. Once a jack is plugged in to the TS socket, signal from the mic or line input is cut off.
Have a look at the schematic for the G9, i'd say that method should work here, of course I could be very wrong.
It would save you a good bit of money too instead of having to fork out for another transformer!
Thanks for all your hard work Greg!
Rob
On the DI input: couldn't you just implement the same method as Jakob used in is G9?
Using a switched TS socket. Once a jack is plugged in to the TS socket, signal from the mic or line input is cut off.
Have a look at the schematic for the G9, i'd say that method should work here, of course I could be very wrong.
It would save you a good bit of money too instead of having to fork out for another transformer!
Thanks for all your hard work Greg!
Rob
bradb
Well-known member
Greg,
Thanks for the detailed response.
I look forward to getting started!
-bb
Thanks for the detailed response.
I look forward to getting started!
-bb
maxwall
Well-known member
- Joined
- Nov 17, 2004
- Messages
- 1,134
Greg,
Is there any plan in a regulating power supply for the filament and B+ voltages.
I know the original does'nt have one , but would this add or detract from the original sound. I assume it would improve it , but have'nt tested that idea yet. Maybe a LM317 on heater regulator and TL783 or Zener diode pair on the output on the B+. Just a thought. I can add 48V phantom easily enough.
I emailed an interest for a board but never heard back. Don't know if you can add me in or if I should just pay
direct ? interested in your masterful creation.
Is there any plan in a regulating power supply for the filament and B+ voltages.
I know the original does'nt have one , but would this add or detract from the original sound. I assume it would improve it , but have'nt tested that idea yet. Maybe a LM317 on heater regulator and TL783 or Zener diode pair on the output on the B+. Just a thought. I can add 48V phantom easily enough.
I emailed an interest for a board but never heard back. Don't know if you can add me in or if I should just pay
direct ? interested in your masterful creation.
helterbelter
Well-known member
The board arrived yesterday, and indeed, it's beautiful !
dripelectronics
Well-known member
ah , glad she arrived !
----------------------
just hooked up a unit with the real 72 transformers / choke and ef-804 tubes ( made an adapter for the tube socket)
vs the lundahl transformers / lundahl choke and ef 806 tubes .
im stunned ,
they seemed to perform equally as well .
hmmmmm.
cool beans /
ps.
regulated power supplies work fantastic with the design ,
i just hooked one up this weekend .
----------------------
just hooked up a unit with the real 72 transformers / choke and ef-804 tubes ( made an adapter for the tube socket)
vs the lundahl transformers / lundahl choke and ef 806 tubes .
im stunned ,
they seemed to perform equally as well .
hmmmmm.
cool beans /
ps.
regulated power supplies work fantastic with the design ,
i just hooked one up this weekend .
