sahib
Well-known member
Udo please?
MICPRE ONE Build Thread
- Thread starter sahib
- Start date
Help Support GroupDIY Audio Forum:
kante1603
Well-known member
Hello all,
I did my first pair of these preamps some days ago.
The package was done the same way as the the EQ One kits,just excellent!
Everything was so well sorted and has the stickers telling values on the baggies.
Told me this will be a fun to build again.
Manual is really cool,same as I said about the EQs.
Schematics were inside too,great!
Will post some more details and pics soon as I'm still on holidays,so it will be next week.
This build has a serious amount of parts,so take your time,patience is the key as always!
I had only basic tools with me and my "51x-Testbox" which is mainly a psu and some breakout stuff like the cardedge connector and xlrs,together with some abilities to switch to different groundings.
And even so it was doable!
Will do listening tests soon to see how they behave,but I was really happy with what I heard so far.
See you soon,
best,
Udo.
I did my first pair of these preamps some days ago.
The package was done the same way as the the EQ One kits,just excellent!
Everything was so well sorted and has the stickers telling values on the baggies.
Told me this will be a fun to build again.
Manual is really cool,same as I said about the EQs.
Schematics were inside too,great!
Will post some more details and pics soon as I'm still on holidays,so it will be next week.
This build has a serious amount of parts,so take your time,patience is the key as always!
I had only basic tools with me and my "51x-Testbox" which is mainly a psu and some breakout stuff like the cardedge connector and xlrs,together with some abilities to switch to different groundings.
And even so it was doable!
Will do listening tests soon to see how they behave,but I was really happy with what I heard so far.
See you soon,
best,
Udo.
Attachments
kante1603
Well-known member
Hello all,
here are some pics from the inside:
Some words about output symmetry and cmrr adjustments.
Symmetry must be done for both the main as well as the monitor output.
This should be done first,after that the input cmrr.Same as on tape recorders(output head,then rec. and erase heads),some of us might remember those days,hahaha...
The manual describes the procedures pretty well,but some of us might not have a signal generator doing the mentioned 50kHz.
Not necessary,even 1kHz sine at +20dBu can bring pretty close results.
There is a provision to skip these procedures,but I wouldn´t do that.
I tried this on both symmetry and cmrr,I ended up in just a 10th,maybe even a twelveth of a single turn on the trim pots to let the dmm jump off from 0vac readings.
If done with a dmm please confirm that yours is capable to read the 1kHz!
If you have better equipment then use it,if your dmm or attached peakmeter can read 20kHz then do adjustments that way.
Just prepare two adaptors with well matched resistors and you´re good to go.
One word on trimming especially the monitor output (VR3):
This must be done with the boards un-sandwiched but connected of course.
Here some pics how they look like,put some isolating cardboard under the subboard when adjusting:
In this position you can do it in an empty rack in the leftmost slot.A bit tricky but doable.
Best of course is doing it with an extender cable outside the rack.
What´s really nice is that oputput symmetry for main out and cmrr for input can be done with the module fully assembled.
Output trimmer (VR2) is reachable directly and the variable cap (VC1) on the mainboard can be accessed through a nice hole in the subboard-clever!
Look here:
Best,
Udo.
here are some pics from the inside:
Some words about output symmetry and cmrr adjustments.
Symmetry must be done for both the main as well as the monitor output.
This should be done first,after that the input cmrr.Same as on tape recorders(output head,then rec. and erase heads),some of us might remember those days,hahaha...
The manual describes the procedures pretty well,but some of us might not have a signal generator doing the mentioned 50kHz.
Not necessary,even 1kHz sine at +20dBu can bring pretty close results.
There is a provision to skip these procedures,but I wouldn´t do that.
I tried this on both symmetry and cmrr,I ended up in just a 10th,maybe even a twelveth of a single turn on the trim pots to let the dmm jump off from 0vac readings.
If done with a dmm please confirm that yours is capable to read the 1kHz!
If you have better equipment then use it,if your dmm or attached peakmeter can read 20kHz then do adjustments that way.
Just prepare two adaptors with well matched resistors and you´re good to go.
One word on trimming especially the monitor output (VR3):
This must be done with the boards un-sandwiched but connected of course.
Here some pics how they look like,put some isolating cardboard under the subboard when adjusting:
In this position you can do it in an empty rack in the leftmost slot.A bit tricky but doable.
Best of course is doing it with an extender cable outside the rack.
What´s really nice is that oputput symmetry for main out and cmrr for input can be done with the module fully assembled.
Output trimmer (VR2) is reachable directly and the variable cap (VC1) on the mainboard can be accessed through a nice hole in the subboard-clever!
Look here:
Best,
Udo.
tgs
Well-known member
- Joined
- May 30, 2013
- Messages
- 80
I just finished my build and what Udo says pretty much sums it up.
The components come in zipper bags and everything is EXTREMELY well organized. I almost drowned in individual bags when I was adding in the resistors.
It's all well marked and it practically rules out making any mistakes.
I took my time building this, and once I was done I was as usual a bit nervous to apply power, but once I did it just worked flawlessly, immediately. I don't have the facility to do the CMRR and SYMMETRY tests so Cemal very clearly informed me about a couple of changes that would let me run it without these tests. So far everything is working as it should!
Unfortunately I will not have time to thoroughly use the module until later this year (touring, etc), but the quick tests I've done so far definitely indicate that the preamp is doing its job and doing it well.
Before building this I have built some guitar pedals, a 51x PSU and rack case and four CAPI 312's. It felt like a daunting task at first from looking at the pictures, but once I started adding in the components that feeling just went away. If you have a good soldering iron and the proper tools, this build is a breeze. Assembly was very easy as well, and the finished module looks stunning. I can definitely recommend this kit and I will get more in the future for sure.
The components come in zipper bags and everything is EXTREMELY well organized. I almost drowned in individual bags when I was adding in the resistors.
It's all well marked and it practically rules out making any mistakes.I took my time building this, and once I was done I was as usual a bit nervous to apply power, but once I did it just worked flawlessly, immediately. I don't have the facility to do the CMRR and SYMMETRY tests so Cemal very clearly informed me about a couple of changes that would let me run it without these tests. So far everything is working as it should!
Unfortunately I will not have time to thoroughly use the module until later this year (touring, etc), but the quick tests I've done so far definitely indicate that the preamp is doing its job and doing it well.
Before building this I have built some guitar pedals, a 51x PSU and rack case and four CAPI 312's. It felt like a daunting task at first from looking at the pictures, but once I started adding in the components that feeling just went away. If you have a good soldering iron and the proper tools, this build is a breeze. Assembly was very easy as well, and the finished module looks stunning. I can definitely recommend this kit and I will get more in the future for sure.
kante1603
Well-known member
Hi,
congrats to your preamp.
Have fun with it!
I have done the EQ ONEs too,they form really cool channel strips with the pres.
Cheers,
Udo.
congrats to your preamp.
Have fun with it!
I have done the EQ ONEs too,they form really cool channel strips with the pres.
Cheers,
Udo.
kante1603
Well-known member
Hahaha....cool idea,but hard to take pics with flashlights.I'm bad at taking pics,that's why I made them in the sunshine (see reply #1,1st pic). ;D
Best,
Udo.
Best,
Udo.
sahib
Well-known member
Yes, the next diy module will be a camera that takes easy pictures of shiny stuff. ;D ;D
