Well done then Wayne, Stereophile should be getting the simple things - like who actually designed the product correct in the first instance.
The stereo version of this board is done and the gerbers off to 6L6. It can be built SE stereo with one board and balanced stereo with two. The silk screen is a bit tight but has all the needed information.
Some pics of the Prototype Purple Pre board in the wild—stuffed and bare—I was fortunate enough to be a guinea pig (SMD parts!! F U N.)... The DIY Store version will be DIYAudio Blue, silkscreen a little different I understand.
Waiting on a chassis (enroute) and I'm ready to wire it up. Thanks Jim and Wayne!
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I still have the two small pink PCBs and for a long time I have considered building preamp mono blocks (two separate chassis) and use a mono volumen pot in each. Also for the headphone output I would mount a mono jack. Doing this I could get 100% channel separation for the headphones but will require I build two mono jack cables for my headphone. I have never seen a preamp built as two mono blocks…...probably because it is not practical with two mono vol. pots etc.?
Something Passlab has considered or has done?
Think it could look "cool"......
Something Passlab has considered or has done?
Think it could look "cool"......
There were quite a few, although not common
Burmester did a double mono pre, and some others.
Downside is cost and complexity obviously, but apart from the tranny quite a few pres are double mono
Have fun
Claude
Burmester did a double mono pre, and some others.
Downside is cost and complexity obviously, but apart from the tranny quite a few pres are double mono
Have fun
Claude
Hello MEPER,
there have been a few DUAL MONO PREAMPS. But with `dual-mono-pricetags'!
- GRYPHON BEL CANTO preamp
- PASS XS Preamp (in two cases: two completely seperated preamp boards `sandwich` - in one case / other case PSU)
for example.
Greets
Dirk
there have been a few DUAL MONO PREAMPS. But with `dual-mono-pricetags'!
- GRYPHON BEL CANTO preamp
- PASS XS Preamp (in two cases: two completely seperated preamp boards `sandwich` - in one case / other case PSU)
for example.
Greets
Dirk
The only real advantage of separate pre and powers amps that I see is that you don’t have to deal with the inevitable ground loops after your sources but separate L/R volume controls are a pain in the butt. Need a way to synchronize the two controls maybe remotely.
to MEPER
- THE GRYPHON PANDORA
- THE GRYPHON SONATA ALLEGRO
very nice dual mono preamps.
Made in Denmark! 😀
Greets
Dirk
- THE GRYPHON PANDORA
- THE GRYPHON SONATA ALLEGRO
very nice dual mono preamps.
Made in Denmark! 😀
Greets
Dirk
I was thinking about a stepped attenuator so you just count clicks…..
My headphone has individual mini jack to each "ear" so easy to use two mono cables if each mono pre has a 6.3mm chassis mount mono jack female.
There should be less "cross talk" this way I assume…...but I have never seen it in practice 🙂
My headphone has individual mini jack to each "ear" so easy to use two mono cables if each mono pre has a 6.3mm chassis mount mono jack female.
There should be less "cross talk" this way I assume…...but I have never seen it in practice 🙂
OK....this one:
Pandora - The Gryphon
He uses a relay based attenuator it seems……
When I see the "price point" I know why I like "DIY"......but it looks nice…..also inside…….
I currently have the original 'mono' versions that Wayne had distributed a long while back so nice to see this new version hitting the diyAudio Store soon.
I see one nice application for it. Use a single board (with a balanced/differential source) and connect to a pair of MOFO boards (one attached to each heatsink, and biased to 2.5A each with a +24V DC supply) and then use it in a balanced input bridged output configuration. Output impedance will double (damping factor will be 20), so about 0.4 ohms output impedance. Should get you loads of power in class A (~nearly 100 watts) as long as Wayne's linestage can swing enough volts to clip the MOFO's. 2nd harmonic will be nearly cancelled which may be something you do or do not want. Similar to an ACA balanced input bridged output monoblock but much better measurements most likely.
Each of these would be one big monoblock Class A amp! 😀
Best,
Anand.
If I go for the large output transistors and lower R11/R12 to 15 ohm for higher bias do I also want to lower output resistor R19 to 15 ohm?