[catfish]

Does this amp have a black background?  Any buzz or hum with sensitive phones like Grados?  Did you have to use dropping resistors on the OPT secondary ?

 

[sceleratus]

I won't say it's dead-bang black.  There is a faint "something" when nothing is playing, but I can't detect it once play is pressed.  Even in classical string tracks where there are dramatic transitions.
 
As an example:
Marianne Thorsen, TrondheimSolistene, Mozart Violin Concerto no. 3 in G major (KV 216) Allegro
 
I have Audeze LCD2 rev 2's  I listened with HD800 at the LA meet for a brief period, however I wasn't able to "zone in" for a good listening session.  Can't comment on the Grado's.   I did NOT implement a dropping resistor on the OPT.
 
In the schematic below are modification Tom provided to help with early noise mitigation as well as support the ECC88 variety valves.  It helped significantly.
 
Next I upgraded some resistors to Texas Components TX2575 bulk metal foil 0.1% and the .22mF capacitors to Mundorf silver oil as noted.  I converted the input and output interfaces to balanced / differential 3-pin XLR.  That required me to replace the ALPS Japan volume POT with a stepped attenuator.  I did this yesterday.
 
Mid- week I will re-wire the inputs with a silk wrapped 26ga. silver wire and a copper braided shield around it.  The final touch will be to install the flexible shaft and turned figured maple knob.  Done.
 
I guess this will be the end of the journey and the thread unless there is something significant to report…… Like putting in insane Royal Princess 300B's or the Takatsuki TA-300B.
 
I wouldn't be that stupid.  nah.
 
EDIT:  The longer it's turned on, the quieter it gets. As in black.
 
 

 
 

 

[sceleratus]

I am Immensely excited.
 
My friend has a huge vinyl collection with rare stuff.  He's been putting most of his efforts into organizing a larger digital collection.  He has a top tier Lynn system.
 
He had tried to digitize the vinyl a few months back and didn't like the results.
 
Yesterday I took my Mac, a MOTU Microbook, and Logic Express over to give it a go.  The results are stunning!  He hasn't got the test tracks scanned into the Lynn library...  I think he will be very happy.
 
The test cuts are.  Miles Davis Kinda Blue, Tracy Champman Revolution, and Beatles Get Back.
 
Logic Express uses "Bounce" mode and writes 24 bit 192K .aif files on the fly.  I think it's as good as any digital recording I have and it has that nice stylus on vinyl quality.

 

[sceleratus]

I now know what I want to build next....  Phono Preamp.
Doable?
 
The recordings I captured were stunning.
A/B comparisons to ripped CD's were hands down better.
I am dumbfounded.

 

[randytsuch]

Quote:

I now know what I want to build next....  Phono Preamp.
Doable?
 
The recordings I captured were stunning.
A/B comparisons to ripped CD's were hands down better.
I am dumbfounded.

http://hagtech.com/cornet2.html

 

[sceleratus]

Quote:

http://hagtech.com/cornet2.html

Thanks Randy

 

[sceleratus]

Full speed ahead learning how to rip vinyl to digital.
 
Here's the analog source equipment:
LP12 Turntable
Akiva Cartridge
Ekos2 Tone Arm
Keel Sub-chassis
Lingo Power Supply
Linto Phono Pre-amp 
Pre-Amp Linn Klimax Kontrol
Amplifiers Linn 6100 and Linn 4200
With Aktiv Crossovers 
Speakers Linn Akurate 242MK 1
Two Linn Melodik Subwoofers
 Digital Linn Akurate DS Streamer
 
Recording equipment:
MacBook Pro Retina SSD
MOTU Microbook
 
Software Choices:
Logic Express 9
MOTU AudioDesk
Audacity
 
The three tracks I captured were done with a whole 20 minutes of seat of the pants learning on Logic Express.  I need to learn how to set input/output recording levels so they don't clip.  Perhaps AudioDesk or Audacity is a better way to go.  ?
 
For a beta test the results were impressing.  I found them far superior to CD recordings of the same material.  However they were not as good as the direct vinyl.  Especially when the volume was cranked.  The clipping was revealed on the Linn system.  It's good, but I think it can be better if I know what I'm doing. 

 

[sceleratus]

Roger's Woodturning finished the knob and sent me a photo.  I should have it tomorrow.
I really like it.  It should look amazing when it's on the amp.
 
 

 

[m2man]

Full speed ahead learning how to rip vinyl to digital.


 


Here's the analog source equipment:


LP12 Turntable


Akiva Cartridge


Ekos2 Tone Arm


Keel Sub-chassis


Lingo Power Supply


Linto Phono Pre-amp 


Pre-Amp Linn Klimax Kontrol


Amplifiers Linn 6100 and Linn 4200


With Aktiv Crossovers 


Speakers Linn Akurate 242MK 1


Two Linn Melodik Subwoofers


 Digital Linn Akurate DS Streamer


 


Recording equipment:


MacBook Pro Retina SSD


MOTU Microbook


 


Software Choices:


Logic Express 9


MOTU AudioDesk


Audacity


 


The three tracks I captured were done with a whole 20 minutes of seat of the pants learning on Logic Express.  I need to learn how to set input/output recording levels so they don't clip.  Perhaps AudioDesk or Audacity is a better way to go.  ?


 


For a beta test the results were impressing.  I found them far superior to CD recordings of the same material.  However they were not as good as the direct vinyl.  Especially when the volume was cranked.  The clipping was revealed on the Linn system.  It's good, but I think it can be better if I know what I'm doing. 

Don't you just want an ADC before his pre-amp? Then you don't lose anything going to speaker and back through the mic. At least it sounds like you are using a mic with the Microbook...

 

[sceleratus]

The MOTO Microbook is an ADC.  It has balanced Line In.  That's where the phono pre-amp is connected.
No Mics.  Using MOTU AudioDesk and QueMix FX software.
 
The results are amazing.  A lot of that can be attributed to an amazing cartridge.
 
Logic Express was horrible.

 

[sceleratus]

Completed the attenuator re-cable using shields.  It passed the DMM test......now for music.   When the maple knob arrives this afternoon the project will be complete.
 
 

 

[nelamvr6]

Awesome! 

 

[sceleratus]

Exactly how I wanted it to look.
Needs a touch of lacquer.
 
 

 

[sceleratus]

 
It feels sooo good to not have to add/fix/change something.
 
Out

 

[nelamvr6]

Quote:

Exactly how I wanted it to look.
Needs a touch of lacquer.
 
 

 
Gorgeous!