Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › Is it possible to build a hybrid and make the tube bypassable with a toggle switch?
New Posts  All Forums:Forum Nav:

Is it possible to build a hybrid and make the tube bypassable with a toggle switch?

post #1 of 14
4/25/11 at 3:24pm
Thread Starter 

Sorry if this is a stupid question or there are already many builds like this, I don't know anything about electronics.

Just thought its a nice idea for multi-genre people like mebeyersmile.png


Edited by YTCrazyTieGuy - 4/25/11 at 3:30pm
Reply
post #2 of 14
4/25/11 at 3:38pm
What would you use in place of the tubes? They're there to provide amplification of some sort. You could put in chips, but that would make the amp more complicated. It'd probably be simpler to have a tube amp and a solid state amp.
Reply
post #3 of 14
4/25/11 at 3:56pm
Thread Starter 

but what if you use the tube only as a preamp to color the sound and leave all the amplification for the opamp? maybe add a resistor right after the tube to negate it's gain? then would you be able to bypass the tube and resistor easily?

(I'm just asking so I can learn)popcorn.gif

Reply
post #4 of 14
4/25/11 at 4:19pm

There was a time in the 1960s when tubes were on their way out in major consumer electronics. They made these electronics which had solid state mounted on tube bases. You could use a simple tube amp like a Woo 3 which has three tubes, have someone make the same tube base with a ss top end. Replace three tubes and now you have ss. Want tubes put them back in. 123.

 

 

It won't be peeerty.


Edited by Redcarmoose - 4/25/11 at 4:22pm
Reply
post #5 of 14
4/25/11 at 4:32pm
Thread Starter 

lolbiggrin.gif

Reply
post #6 of 14
4/25/11 at 4:54pm
Thread Starter 

what i'm basically asking is: if you can take an entry level diy hybrid (such as the starving student), add a relatively colorless resistor after the tube(s) to negate the gain of the tube(s), use a higher output opamp, and add some sort of bypass (such as what's used for crossfeed) and a toggle switch, how would the bypass work? will you be able to get two sounds out of one cheap amp? will it work?

Reply
post #7 of 14
4/25/11 at 5:03pm

Check out the Peachtree Nova, it implements a feature similar to what you're talking about. I'm not sure exactly what purpose the tube serves in the circuit but it is defeatable via button on the amp or remote.

Reply
post #8 of 14
4/25/11 at 6:45pm

I think what the OP really wants is a bypassable "tube buffer" stage, which he could put right in front of any solid state amp.  In this case, the amp would always run through the solid state devices, which would still do all the amplification, but an optional tube stage at the front could be used to add whatever tube color he wants. 

 

Does this sound like what you want, TieGuy? 

Reply
post #9 of 14
4/25/11 at 6:49pm
Thread Starter 

Ya exactly!

Reply
post #10 of 14
4/25/11 at 6:52pm
Thread Starter 

So your saying I need to first find a ss build I like and then a "tube buffer" stage instead of doing a big mod to a hybrid? How can I build that sort of buffer stage?


Edited by YTCrazyTieGuy - 4/25/11 at 6:57pm
Reply
post #11 of 14
4/25/11 at 6:57pm

Precisely.  Making a hybrid/ss switchable would be quite a challenge, as far as I can tell: even circuits which allow for certain stages to be either tube or ss still have so many differences in other parts that a simple "switch" would be pretty much impossible.  I suppose it could be done with enough design time and relays, but that would be an incredible project that in the end would just be a compromise - the kind of person who would build such a device would do so for the challenge alone, I think. 

 

By putting in the tube buffer in the beginning, you can "flavor" the sound of a ss amp at your leisure :)  It will be much simpler to build, and more versatile. 

Reply
post #12 of 14
4/25/11 at 7:00pm
Thread Starter 

Cool thanks!

So what kinds of tube buffers could I go for? are there good designs you know?

Reply
post #13 of 14
4/26/11 at 11:03am

Are you comfy working with ~150Vdc or more? 

 

At slightly less dangerous voltages, you may like the results from building REALLY simple SS circuits with no global feedback. Check out the szekers on headwize for an example, or skim the preamp section on diyaudio for others. IME a LOT of the SS sound comes from the absolutely unchecked use of global feedback: SS amps without global feedback sound just a touch looser than the normal rock-hard SS sound to me, and I like it :)

 

At high voltages: a simple cathode follower with input and output caps works well. 

Valvewizzard FTW!

Reply
post #14 of 14
4/27/11 at 1:15pm
Thread Starter 

Thanks for the advice, I think I'm going with the JDSlabs Cmoy. From this http://www.headfonia.com/60-pack-of-awesome-jdslabs-cmoy/#disqus_thread Review I learned it should be a very good synergy with my HD668Bs. Maybe I'll get a tube buffer in the future.

Reply
New Posts  All Forums:Forum Nav:
  Return Home
Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › Is it possible to build a hybrid and make the tube bypassable with a toggle switch?