Deaj
Silver Supporting Member
- Messages
- 4,676
Hello all,
I've been out of circulation for a while. I've had precious little free time as of late and, feeling somewhat better (recently diagnosed with Psoriatic Arthritis), I've been spending more and more free time playing and less time breathing solder fumes. It's been good! I was starting to burn out on building pedals.
I've been thinking about building another guitar amp recently (specifically a 5E3 tweed Deluxe) though the cost of such a project has kept me from moving forward on it. Through other circumstances I got an idea for a more reasonably priced project - a solid state bass preamp with an old school sound. I've owned several great sounding bass amps over the last 15 or so years and my favorite too date has been the now out of production Ampeg 'Blue Diamond' series B-50R Rocket Bass 50watt 1x12 combo. It was voiced to sound like an old B-15N and it really covered that sound wonderfully.
Ii just sold my B-50R to help pay for a bass amp suitable for gigging / playing with a drummer (the B-50R, at 50w SS was never up to the task without solid sound reinforcement. I did have the opportunity to use my B-50R on a few gigs by running the line out to the effects return on more powerful bass amps and with excellent results. I've had to turn down quite a few requests to play bass for a jam due to not having an amp capable of being heard in the same room as a live dfummer. So away went my much beloved B-50R To make room for a new Markbass Jeff Berlin 1x15 300w combo.
A few days later I began to regret selling the Ampeg even though it was clearly not meeting my needs all around (plus I don't have sufficient space for two bass amps). It occurred to me last night that I definitely have room for a preamp and it's the preamp portion of the B-50R that I miss. Then I began to wonder how feasible it might to build the B-50R's preamp as a DIY project. Hmmmm.....
I called Ampeg this morning and asked if I could purchase a schematic for the now discontinued B-50R. The tech rep asked me for an email address and then asked me to check my inbox. Sure enough they sent a full schematic and for free!
The preamp is based around a TL074 quad op-amp IC and relatively simple. I found a Hammond transformer ideally suited for this project and I believe I've sorted out the power supply.
Next: circuit layout for a perf-board build. I love doing layouts! Aside from seeing/hearing a new build fire up and work for the first time the layout and diagram are my favorite part of these projects. I'll post links to the schematic and my initial preamp circuit layout (sans power supply - ran out of time tonight) in a few minutes. I'll be sure to post updates as I make progress.
Second revision preamp circuit board layout:
First revision power supply board layout:
Ampeg B-50R schematic (in .pdf format): http://home.centurytel.net/flanneldrawers/B50R_schematic.pdf
I've been out of circulation for a while. I've had precious little free time as of late and, feeling somewhat better (recently diagnosed with Psoriatic Arthritis), I've been spending more and more free time playing and less time breathing solder fumes. It's been good! I was starting to burn out on building pedals.
I've been thinking about building another guitar amp recently (specifically a 5E3 tweed Deluxe) though the cost of such a project has kept me from moving forward on it. Through other circumstances I got an idea for a more reasonably priced project - a solid state bass preamp with an old school sound. I've owned several great sounding bass amps over the last 15 or so years and my favorite too date has been the now out of production Ampeg 'Blue Diamond' series B-50R Rocket Bass 50watt 1x12 combo. It was voiced to sound like an old B-15N and it really covered that sound wonderfully.
Ii just sold my B-50R to help pay for a bass amp suitable for gigging / playing with a drummer (the B-50R, at 50w SS was never up to the task without solid sound reinforcement. I did have the opportunity to use my B-50R on a few gigs by running the line out to the effects return on more powerful bass amps and with excellent results. I've had to turn down quite a few requests to play bass for a jam due to not having an amp capable of being heard in the same room as a live dfummer. So away went my much beloved B-50R To make room for a new Markbass Jeff Berlin 1x15 300w combo.
A few days later I began to regret selling the Ampeg even though it was clearly not meeting my needs all around (plus I don't have sufficient space for two bass amps). It occurred to me last night that I definitely have room for a preamp and it's the preamp portion of the B-50R that I miss. Then I began to wonder how feasible it might to build the B-50R's preamp as a DIY project. Hmmmm.....
I called Ampeg this morning and asked if I could purchase a schematic for the now discontinued B-50R. The tech rep asked me for an email address and then asked me to check my inbox. Sure enough they sent a full schematic and for free!
The preamp is based around a TL074 quad op-amp IC and relatively simple. I found a Hammond transformer ideally suited for this project and I believe I've sorted out the power supply.
Next: circuit layout for a perf-board build. I love doing layouts! Aside from seeing/hearing a new build fire up and work for the first time the layout and diagram are my favorite part of these projects. I'll post links to the schematic and my initial preamp circuit layout (sans power supply - ran out of time tonight) in a few minutes. I'll be sure to post updates as I make progress.
Second revision preamp circuit board layout:
First revision power supply board layout:
Ampeg B-50R schematic (in .pdf format): http://home.centurytel.net/flanneldrawers/B50R_schematic.pdf
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