Hey Grey, have you had a chance to listen to the ZVP3310 or its mate, the ZVN3310? If so, how do they measure up with jfets?
Carpenter,
Hands down the jfet (2sj74) beat the zvp3310 as input buffer on my Zv4. The mosfet didn't go to waste though as it was used for cascoding the jfet🙂 It's a big improvement across the audio band.
Allan
Hands down the jfet (2sj74) beat the zvp3310 as input buffer on my Zv4. The mosfet didn't go to waste though as it was used for cascoding the jfet🙂 It's a big improvement across the audio band.
Allan
Hi Blues,
Did you have a chance to use both transistors as a buffer/source follower?
I'm so impressed with the sound quality of the ZVP3310--how does the jfet beat it? What is the difference in their sound quality?
Did you have a chance to use both transistors as a buffer/source follower?
I'm so impressed with the sound quality of the ZVP3310--how does the jfet beat it? What is the difference in their sound quality?
carpenter said:
On the plus side, they can take more voltage and dissipate a little more heat. On the minus side, they have somewhat higher capacitance. When all is said and done, I prefer bigger MOSFETs in TO-220 cases because they can take more heat than the E-line. 625mW just isn't that much of an improvement over the J310's 350mW.
I run TO-220s up to something like .5 to .75W naked. With a heatsink you can get a lot of heat out of a TO-220. My Aleph 2s use TO-220 output devices, albeit water-cooled in order to move the heat around more efficiently.
Don't get me wrong, the Zetex parts are nice, they're just not what I'm looking for right now. It's quite possible that I might end up using them for something else later on.
Of course, it'd be really spiffy if the J310 could take more heat. And while I'm at it, can I have the LU1014D in a TO-247 case...and...
Grey
carpenter said:
Yes, as the zvp3310 was the original buffer. When NP gifted me with the Buffer for Blues using a jfet input, I added cascoding to keep the jfet happy and Christened it Blues Buffer's Brother.
I used to miss the stock Aleph 3 top end when switching to the original Zv4...not the case now. With the jfet it has an added sparkle on highs and is more "romantic" sounding. The A3 has a tendency to be non-forgiving on bad recordings. The Zv4jC is I think harmonically richer. Here's the link....
http://www.diyaudio.com/forums/showthread.php?s=&threadid=66397&perpage=10&highlight=&pagenumber=1
Nelson Pass said:
Fantasy A : Something hot with balanced inputs that can be scaled to drive even a K1000.
Fantasy B : Paint a woman with a single brush, Lim.Ed. and signature included.
(spouse model allowed, if bucknaked)
(Fantasy C : Grant permission to use the UGS for a non-commercial lower power/extreme bias X###.0)
I would like a switchable amp. A nice ten watt Zen V9 like amp with a switch to turn it into a 100 watt bass crushing party amp. With a volume control of course. Mabe a picture of Allison Goldfrapp on the board. 😎
Maybe a subwoofer output?
Maybe a subwoofer output?
How about an integrated amp? 
JUST KIDDING! 🙂
Is it possible to improve on the Zen V9 without treading on what
may be the First Watt F4s toes?
JUST KIDDING! 🙂Is it possible to improve on the Zen V9 without treading on what
may be the First Watt F4s toes?
How about a balanced V9? I guess that's too easy for Nelson to worry about, how about some of the rest of you guys?
Variac said:
make two stereo ZV9s
leave out output elkos
and you have bal in-bal out two mono-blocks
you don't even need sketch or schmtc for that
but- if you insist on Susy one,that's tricky........at least for me , if more complexity is not an option ........
That should work. Of course sometimes it's worth mentioning something to Nelson and he thinks: "That's too easy, but what if we do this....wait! if we do that , then we can do this!...." and before you know it, something different and new pops up!
Zen Mod said:
Variac said:
if you wish...........imagine two mirrored ZV9 channels (exactly one stereo drawn mirrored) ;
without output caps (or even with them,but why....) , etc......this is exactly one bal in -out monoblock;
now-if we add current sink (along with negative supply) ,instead of ground reference - mutual for both halves.......then we have sort of ZV9 LTP ..........or susy ZV9..........
is that OK for ya?
or I'm wrong ........as often I am
with approach like that,seems that added complexity can't be step backwards......in try to achieve susy
I've been playing with the On-Semi J310 (Digikey has them) and have also been finding them a decent substitute for the 2sk170. The only downside I find is the the Vgs(off) tends to be larger in value than what the 2sk170's give, so that you have to eat a little more voltage when using them. The On-Semi J310 looks to be the same as the Vishay and Fairchild version, and On-Semi also has a J309 with a little lower Idss and a little higher transconductance.
Another alternative I have been trying out is the On-Semi 2N5486.
Cheers, Terry