My DIY Tube preamp

[jomar]

I've been using branded preamps for a while and also been upgrading the parts to improve the sound . End-up what's left on the preamp are the chassis , transformers and the main pcbs Quite ironic

Inspired by the works of master DIYers here in WS like Hypertriode, Tony, Alexg , Amandarae and others .. i've decided to sell the branded preamp and just DIY a preamp with good quality parts since i have some parts lying around also

Here are some teasers ... more pictures coming soon ....

[alexg]

Those V-caps are nice.

[vintage_dog]

jomar, good luck on your project. i can almost hear how it will sound

--toroidal power trans, ss rectifiers, tube stages (total 3 tubes?), great coupling caps, riken carbon resitors, step attenuator, will it use 12au7s? hmmm are you still missing some more caps for the ps?

[hypertriode]

Go, go, go Jomar!!!

[jomar]

Those V-caps are nice.

Yup , removed from my upgraded branded preamp .. very nice sounding caps

[jomar]

jomar, good luck on your project. i can almost hear how it will sound

--toroidal power trans, ss rectifiers, tube stages (total 3 tubes?), great coupling caps, riken carbon resitors, step attenuator, will it use 12au7s? hmmm are you still missing some more caps for the ps?

Thanks for the compliments sir

Two 12AU7 tubes and tube rectified ( 6V4 or EZ80 ) followed by a SS regulated psu for the B+ . Still got some Mundorf Mcaps and Obbligato Oil cap but i'm not sure if still can fit on the chassis.

[jomar]

Go, go, go Jomar!!!

Thank you sir .. hope it will sound good

[jomar]

Just an update on my DIY preamp. My DIY kids started to help me build it

[jomar]

..... more pictures

Preamp Section ( Component view )


Preamp Section ( Top view with tubes )


B+ Voltage Regulator . Used a PCB but component are soldered point-to-point


The Chassis …..


The chassis with some components populated .


Need more time to do the soldering then will proceed with the External Power supply :

[endrik35]

Ganda! Padinig pag nabuo ha?

[jomar]

Ganda! Padinig pag nabuo ha?

Thanks for the compliment sir . No problem .. Hope no smokes/sparks when completed.

[hypertriode]

Looking good Jomar!

[jomar]

Looking good Jomar!

Am trying to make the layout/wirings as neat as possible just like your creations atleast maski sa layout at cosmetic lang panalo na still a lot of work to do ....

[s2kov]

woohoo!

Nice project jomar!

[jomar]

woohoo!

Nice project jomar!

Salamat ser .. Pero wala ito sa kalingkingan ng mga projects mo

[m_shoe_maker]

Just an update on my DIY preamp. My DIY kids started to help me build it

Wow! These guys are the future Van Alstines!

[jomar]

Wow! These guys are the future Van Alstines!

Hope one of them will be sir they have the same passion in music

[Chuckyboy]

..... more pictures

Preamp Section ( Component view )


Preamp Section ( Top view with tubes )


B+ Voltage Regulator . Used a PCB but component are soldered point-to-point


The Chassis …..


The chassis with some components populated .

Need more time to do the soldering then will proceed with the External Power supply :

WOW! these parts make me drool

Is the circuit design from a kit? or designed by you sir? Either way, very very nice project

[jomar]

WOW! these parts make me drool

Is the circuit design from a kit? or designed by you sir? Either way, very very nice project

It's a Cloned preamp sir . I copied the circuit but used better parts. I decided to build it as the parts were minimal and only using 2 tubes. Furthermore, i've used the orig preamp and so far i like the sound & it matches my system. Ako na dumiskarte sa parts layout based on the chassis that i have.

[jomar]

Just an update on my DIY preamp.

Finished Preamp section


External Power Supply


Hooked-up for Voltage measurement … so far no smokes and sparks . Voltages are ok .


Preamp Burn-in using XLO Test and Burn-in CD


Now playing 


I could not believe I was able to make this preamp work within first try .
The sound ?? Played some LPs and CDs last night . The vocals are clear and smooth. The highs are not that extended yet ... the bass is bold but not as low as i expected. Will need more burn-in and hear how’s the improvement .

Three issues need to resolve …
1. Increase the Heater voltage to 6.3Vdc .. maybe will try LT317 voltage regulator. Maybe this will yield to sonic improvement also ??
2. A slight hum within few inches when heard close to speaker but increase when preamp is OFF ( Tube amp is ON ) ... maybe some ground loop ?
3. Make an Aluminum or maybe Wood Faceplate for pogi looks

Thanks for looking