Hello ... on this project I have decided to make the phono preamp with the original power supply when available as a kit from Hart electronics.
These pcb's are no longer available so have made my own as a exact replica .. purely for retro .. nostalgic reasons
I like the PCB for central star earthing plus can be used for many other projects if needed .. also I have used 2oZ copper for the PCB tracks
more to follow when completed
These pcb's are no longer available so have made my own as a exact replica .. purely for retro .. nostalgic reasons
I like the PCB for central star earthing plus can be used for many other projects if needed .. also I have used 2oZ copper for the PCB tracks
more to follow when completed
Attachments
Ok people .. some more in progress pics from tonight
so a rear view .. we have mains in and power indicator at the rear
2 sets of inputs (MM & MC) plus the output phono sockets .. just need to add the MM /MC switch and the PSU earth lift switch .. then some engraving to finish the rear off
regards
so a rear view .. we have mains in and power indicator at the rear
2 sets of inputs (MM & MC) plus the output phono sockets .. just need to add the MM /MC switch and the PSU earth lift switch .. then some engraving to finish the rear off
regards
Attachments
Hello James, (or is that the cat's name)
That's looking very good so far, took me a little while to work out what you meant by cats eyes! Obvoiously your 'trademark'.
ISTR that Hart did kits for ETI magazine projects. Was this one of them ? If so, do you know which ETI issue it was in ?
That schematic you posted is the same as the one on Paul Kemble's site. The specs at the bottom have quite a few typos. Nothing important but I'll post corrections later.
I also noticed on the Kemble page that there may have have some mods, like reducing gain of MC input to mitigate bass roll-off. Did you get any documentation like updated schematic, updates, etc. with your board ?
I'm currently looking at phono-preamps for a new preamp build. I put this one into LTspice and on 1st look it's pretty good - very flat RIAA eq, except for a little bass roll-off from the 13Hz rumble filter. This is a candidate, also it's op-amp based cousin the K1500. I just want to work with the correct upto date circuit, that's all.
Cheers,
Simon
That's looking very good so far, took me a little while to work out what you meant by cats eyes! Obvoiously your 'trademark'.
ISTR that Hart did kits for ETI magazine projects. Was this one of them ? If so, do you know which ETI issue it was in ?
That schematic you posted is the same as the one on Paul Kemble's site. The specs at the bottom have quite a few typos. Nothing important but I'll post corrections later.
I also noticed on the Kemble page that there may have have some mods, like reducing gain of MC input to mitigate bass roll-off. Did you get any documentation like updated schematic, updates, etc. with your board ?
I'm currently looking at phono-preamps for a new preamp build. I put this one into LTspice and on 1st look it's pretty good - very flat RIAA eq, except for a little bass roll-off from the 13Hz rumble filter. This is a candidate, also it's op-amp based cousin the K1500. I just want to work with the correct upto date circuit, that's all.
Cheers,
Simon
I will try and upload a PDF later .. this was the original Hart shunt feedback kit k1450 this has had many favorable reviews from Vinyl enthusiasts .. I built the less complicated op amp version years ago and was very pleased with the results .... plus I am going to purchase a turntable hence this project ...
regards
regards
Yes the sensitivities should read ... 3.7mV (mm), 340uV (mc).
The gain numbers are correct .
I have recently encountered this in the thread started by... Anthony.taylor1967...( Gain resistors on JLH phono ) over in analogue source.
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