Well, I do agree with juma for once, to be perfectly honest.
It is difficult to sell an opamp gain stage and a source follower as a headamp that is supposed to stand out from the rest.
There are many of those around, on top of dedicated headphone amp ICs.
And there are also many fully discrete, well published designs, like that from Richard Marsh, e.g.
Cheers,
Patrick
It is difficult to sell an opamp gain stage and a source follower as a headamp that is supposed to stand out from the rest.
There are many of those around, on top of dedicated headphone amp ICs.
And there are also many fully discrete, well published designs, like that from Richard Marsh, e.g.
Cheers,
Patrick
nothing wrong with economic version , made by Big Guys
as I said previously , I would make it even more peasant , invest some in two UPS Accus and simple charger , et voila
take it as Volks B1 Cousin
note - moi not interested neither in this one nor big PL headamp ....... just thinking from regular Greedy Boy boots
as I said previously , I would make it even more peasant , invest some in two UPS Accus and simple charger , et voila
take it as Volks B1 Cousin
note - moi not interested neither in this one nor big PL headamp ....... just thinking from regular Greedy Boy boots
The exciting thing about this project (other than it sounds fantastic... 🙂 🙂 🙂 ) is that being an all-on-one PCB, it will be very quick and straightforward to build.
6L6, were you using the OPA2604 when you stated that "it sounds fantastic", or some other op-amp(s)?
Thanks...
Thanks...
Yes, I've tried the OPA2604 and the LM4562 so far. Both are excellent, and the HPA works well with either. I slightly prefer the 2604, but I'm not a good enough writer to articulate the differences...
The interesting thing is that the circuit is more than clean enough to hear the differences in opamps. That's quite fun. 🙂
I've put in a Mouser order recently and there are a handful of other opamps I'm going to try.
The interesting thing is that the circuit is more than clean enough to hear the differences in opamps. That's quite fun. 🙂
I've put in a Mouser order recently and there are a handful of other opamps I'm going to try.
This amp is meant to be easy to build not really SOTA but it performs quite well. The use of a dual Op amp makes it very easy to build even for a first timer and you can roll in all kinds. Three terminal regulators are also nice and easy to use and work well enough for this kind of project. A satisfying afternoon build.
I do have a day job that takes time, lots of new Pass products entering production and an airplane project 6L6 is helping me out on.😉
I do have a day job that takes time, lots of new Pass products entering production and an airplane project 6L6 is helping me out on.😉
I learned few things about PL gang in last few yrs :
- never doubt in their capability to make even better (plenty of reasons for present status)
- never doubt in their good intentions
- they're still young , Greenhorns in fact ......... plenty of time to play with real deal ....... toobz
- never doubt in their capability to make even better (plenty of reasons for present status)
- never doubt in their good intentions
- they're still young , Greenhorns in fact ......... plenty of time to play with real deal ....... toobz
I recognize an awful lot of those parts... The type a kindly jolly elf buys by the pallet... 🙂 🙂 🙂
🙂.....................No more led's on the board unfortunately!
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I had a bit of time to play with the prototypes today...
Using LED as a voltage reference, lifting the fixed 15V regulators up by two volts, to give 17V rails. Very easy, very precise.
Bipolar transistors on the output. (I told yo the bias scheme was really cool...) These are BDW93/94CFP
Trying a remote mounted pot - this is a 20K Alps RK097 and a cute little eBay board to make soldering easier. Don't let the size fool you, this is a nice pot.
More opamps being tested, this is a OPA1642 on a SOIC-DIP adapter. Nice. Very nice. 🙂
Using LED as a voltage reference, lifting the fixed 15V regulators up by two volts, to give 17V rails. Very easy, very precise.
Bipolar transistors on the output. (I told yo the bias scheme was really cool...) These are BDW93/94CFP
Trying a remote mounted pot - this is a 20K Alps RK097 and a cute little eBay board to make soldering easier. Don't let the size fool you, this is a nice pot.
More opamps being tested, this is a OPA1642 on a SOIC-DIP adapter. Nice. Very nice. 🙂
Looking good, 6L6!🙂
I didn't know you could use Darlington transistors in place of MOSFETs.
Is there much difference in DC offset using them?
Also, may I ask where you got your shielded cable from? I've been cutting up some of my inexpensive interconnects, but most seem to have wire inside them about the size of hair.😡
I didn't know you could use Darlington transistors in place of MOSFETs.
Is there much difference in DC offset using them?
Also, may I ask where you got your shielded cable from? I've been cutting up some of my inexpensive interconnects, but most seem to have wire inside them about the size of hair.😡
I hope the somewhat alternative heatsink mounting style in the second pic isn't going to be the standard? 😀
/U.
/U.
As you suspect, yes. So it may not be suggested for the stand build.
But it's still really neat that it works.
It's Mogami cable for balanced interconnects. Nice stuff - I really like Mogami wire. Good copper, flexible, good shielding, nice materials, easy to work with.
I suppose if you want to you could... but it's not suggested, no.
🙂