pls suggest a project

[lordearl]

I recently fried my Vincent KHV-1 headphone amp/preamp and so have decided to gut the chassis and build something (better ) in its place.

The following is installed in the chassis;
2 pairs of RCA inputs
1 pair RCA outputs
IEC power socket
Fuse
ALPS volume pot
230V transformer with 220V, 17V, 17V, 15V secondaries
1/4" headphone jack output

Anyone have some suggestions as to a schematic (tube, SS or hybrid), which might utilize all this gear and also suit the transformer?

[Cassiel]

HeadWize - Project: The Morgan Jones Mini Tube Headphone Amplifier by Chu Moy


Search in this forum for a regulator circuit for the filaments voltage and you're done. You'll also have to adjust your B+ but that is easy.

[Eli Duttman]

Originally Posted by stalker

HeadWize - Project: The Morgan Jones Mini Tube Headphone Amplifier by Chu Moy


Search in this forum for a regulator circuit for the filaments voltage and you're done. You'll also have to adjust your B+ but that is easy.

Looks like MJ planted the seed of a beautiful flower.

LE, bridge rectify, filter, and Maida regulate the "220" VAC winding into 220 VDC. Use 3X Russian 6H23П-EB (6n23p-ev) tubes and wire the heaters in series, with V1 in the middle. FW rectify the 2X 17 VAC windings, filter, and current regulate the resulting rail at 300 mA., to power the series heater string.

[lordearl]

Thanks folks.

Sounds like a plan, complex as a first DIY project but slowly does it. Might even post a few pics, etc, as we go.
First up, two questions;
(1) Would this be one the most basic tube headamps with the least components in the signal path?
(2) If so, what is "LE" and "FW"?

[Cassiel]

Oh, first one? Just ask a lot of questions. It's easy, start with the signal circuit... power supply is the complicated part. You can skip regulating the B+, RC filters are OK. You can add a Maida regulator later on or you can buy one made; there are some regulator kits, TubeCad sells them cheap.

LE I think is you, FW is full wave bridge, getting DC from AC with diodes.
Yeah, good and simple headphone amp.

[Gordy]

Originally Posted by lordearl

Thanks folks.

Sounds like a plan, complex as a first DIY project but slowly does it. Might even post a few pics, etc, as we go.
First up, two questions;
(1) Would this be one the most basic tube headamps with the least components in the signal path?
(2) If so, what is "LE" and "FW"?

(1)
Not necessarily the most simple, but certianly worth the effort with decent performance, and a good learning project too.

You do not need the least components in the signal path, you need the right number to get the right performance!

See more on this design here (click):

The Cavalli Jones Headphone Amplifier
The Cavalli Jones Headphone Amplifier
The Cavalli Jones Headphone Amplifier
The Cavalli Jones Headphone Amplifier
Cavalli Audio

(2)
lordearl
lord earl
Lord Earl
LE


: )

[lordearl]

Excellent - thanks for helping me work out who I am! Always an important first step!

After reading through the excellent pages you all suggested, I found this brilliant build diary;

HeadWize - Project: The 6N1P OTL Headphone Amplifier by Bruce Bender

Even has a complete parts list and wiring diagram.

I can't use the Hammond 269AX as it's not 240VAC, but is there any way of modifying the circuit to use the transformer already wired in?

[Cassiel]

I can't use the Hammond 269AX as it's not 240VAC, but is there any way of modifying the circuit to use the transformer already wired in?

The Cavalli Jones Headphone Amplifier

There's your modified circuit.
Same white cathode follower but different values for different tubes.
You can follow the same wiring diagram.