On the contrary thank you for that great link 🙂
I have always been partial to Sennheiser headphones ever since i had a pair of HD414 back in the day. Looks as though i need to get a listen to either of the HD515, 555 & 595. I can just bet there will likely be none in stock in this place though, no i'm wrong - John Lewis stock the 515 😀
Again, thanks for the link Mooly
Still playing around with the layout... exceeded the 250 pin limit on Diptrace lol... but you can still place pads one at a time... yea 🙂
This is looking like the final design. Need to check that the sockets, pot and switch etc will all position perfectly to allow the PCB to slot into the rather nice case.
This is looking like the final design. Need to check that the sockets, pot and switch etc will all position perfectly to allow the PCB to slot into the rather nice case.
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It all works, and sound quality is outstanding.
It's getting there slowly...
PCB assembled... all worked first time... yea.
Just gave it a quick listen... wow 😉 this is good. And it's so quiet too.
Next will be the case etc... that's the bit I don't like doing.
The mutiturn pot (between the battery and transformer) allows the low battery warning to be set accurately. The small push tact switch is illuminated (Red L.E.D.) and this begins to flash when the battery pack needs charging. You will see why I settled on red rather than blue hopefully in the next installment.
It's getting there slowly...
PCB assembled... all worked first time... yea.
Just gave it a quick listen... wow 😉 this is good. And it's so quiet too.
Next will be the case etc... that's the bit I don't like doing.
The mutiturn pot (between the battery and transformer) allows the low battery warning to be set accurately. The small push tact switch is illuminated (Red L.E.D.) and this begins to flash when the battery pack needs charging. You will see why I settled on red rather than blue hopefully in the next installment.
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You are really something!
Best regards & good listening,
Obe1
Hi Obe1 and thank you 🙂
This amp will hopefully allow me to evaluate some different "front end" circuitry in future. Input stages, tone controls, solid state switching etc.
Is it giving you ideas 😉 ?
Hi Mooly
I just found this thread. Maybe it will give me something to use up my supply of reclaimed trannies !!
Was the choice of transistors deliberate of governed by what you had in the junk box ???
Andy
I just found this thread. Maybe it will give me something to use up my supply of reclaimed trannies !!
Was the choice of transistors deliberate of governed by what you had in the junk box ???
Andy
Hi Mooly, i meant to leave a comment yesterday but i was short of time as i went out...
Very neat indeed, i wish i had time to make my own PCBs but alas i'm a veroboard man 😀 Nothing wrong with the stuff when it's layed out correctly though 🙄
You got exactly what you wanted 🙂 Even though your efforts should have reminded me i have still managed to get into town 3 times lately & i have still forgotten to get a listen to some Sennheiser cans
All the best & enjoy, Mark.
Very neat indeed, i wish i had time to make my own PCBs but alas i'm a veroboard man 😀 Nothing wrong with the stuff when it's layed out correctly though 🙄
You got exactly what you wanted 🙂 Even though your efforts should have reminded me i have still managed to get into town 3 times lately & i have still forgotten to get a listen to some Sennheiser cans
All the best & enjoy, Mark.
You got exactly what you wanted 🙂 Even though your efforts should have reminded me i have still managed to get into town 3 times lately & i have still forgotten to get a listen to some Sennheiser cans
Memory is the second thing to go with age. I forget what the first one was...
(Lurking here because I have a large collection of germanium transistors, including power types such as AC127/AC128, OC28 and OC35.)
Finished... what was that about a red LED ?
Hmmm... I mangled the switch a bit playing around with fitting it. Pity as the red looked rather good. Should have realised that mounting it on the PCB was no good as the slightest movement would cause it to bind and stick. In the end made two brackets from PCB and drilled the front, but not deeply, to provide a good key to epoxy these in place. The switch is then soldered to this... perfect alignment that won't shift.
Listening tests again confirm how right this sounds, and as mentioned how quiet it is. Even when running on mains (charging) it's totally silent, not a trace at all of mains hum/buzz etc which is just as it should be.
So there we go... job done 🙂
Hmmm... I mangled the switch a bit playing around with fitting it. Pity as the red looked rather good. Should have realised that mounting it on the PCB was no good as the slightest movement would cause it to bind and stick. In the end made two brackets from PCB and drilled the front, but not deeply, to provide a good key to epoxy these in place. The switch is then soldered to this... perfect alignment that won't shift.
Listening tests again confirm how right this sounds, and as mentioned how quiet it is. Even when running on mains (charging) it's totally silent, not a trace at all of mains hum/buzz etc which is just as it should be.
So there we go... job done 🙂
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Thanks... it's one of those projects that just seemed to work out well.
Won't be able to make Sheffield I'm afraid.
Won't be able to make Sheffield I'm afraid.
Very nice work! Good to see someone that's still into Germies these days. Any Idea on a max power output? It'd be cool to scale this up to a few watts to spank some efficient full-range drivers.
Hi Jaycee,
The case is one of these,
Box Enclosures - Product
and I got it from CPC early in the year but I have a feeling they stopped doing them.
The case is one of these,
Box Enclosures - Product
and I got it from CPC early in the year but I have a feeling they stopped doing them.
Ahh, never thought to look at CPC for enclosures!
Rapid have the Hammond 1455's which look nice. Will probably use one of those, but i like the cool electric blue look of the case you had 🙂
Rapid have the Hammond 1455's which look nice. Will probably use one of those, but i like the cool electric blue look of the case you had 🙂
