Ross, in your opinion does it make sense to use this circuit for a buffer with both input and output unbalanced? (I yet don't understand if it makes sense for X-BOSOZ too...)
Will it be stable at unity gain?
In order to use it with OPA1632 something should be added perhaps ("control for common mode offset" Mr. Pass said)?
Will it be stable at unity gain?
In order to use it with OPA1632 something should be added perhaps ("control for common mode offset" Mr. Pass said)?
st2_998 said:
It would work SE-IN/SE-OUT but it might be a waste since you would not get much benefit from the chip. If you want an SE buffer I would look at something like the "Kookoo" which I design specifically as an SE linestage/buffer for the Joshua Tree (it is designed to stack).
I believe OPA1632 should work just fine without any circuit modifications. You just may need to play with the resistor values a little. I will have to dig into the datasheet and see if I can find any clear changes to make.
Cheers!
Russ
Russ, I have to repeat the question: Do you ever sleep?
I am wondering if this circuit sounds as good as a purebreed Twisted BosoZ?? If this was not in the middle of the fishing season, I would build one right away
Very good work, and very kind of you to share the pdf's If you continue like this, you might start the whole tube/solid-state discussion all over again Just with X'ed chips and mosfets as subjects
Steen
I am wondering if this circuit sounds as good as a purebreed Twisted BosoZ?? If this was not in the middle of the fishing season, I would build one right away
Very good work, and very kind of you to share the pdf's If you continue like this, you might start the whole tube/solid-state discussion all over again Just with X'ed chips and mosfets as subjects Steen
Hi Guys,
As to the library I will share it here shortly.
Here is the link to the KooKoo:
http://www.diyaudio.com/forums/showthread.php?postid=901534#post901534
It is also designed to stack with the JT.
As to the library I will share it here shortly.
Here is the link to the KooKoo:
http://www.diyaudio.com/forums/showthread.php?postid=901534#post901534
It is also designed to stack with the JT.
sorry had nothing to do (waiting for a taxi 
Blimp said:
Cost should be near $50 for a kit, but we will need to determine that actual price based on our cost which has yet to be determined. (if I can just get off my duff and get them made). You can use the JT at either end of the TS. I like it with the JT in front of the TS for the lowest possible output impedance (next to nothing).
I am very pleased with the results so far, this preamp (well a pair of them) has found its home in my main system now driving a pair of "Twisted X Overture " monoblocs.
So now I have a completely balanced signal chain from DAC to speaker.
Cheers!
Russ
Russ White said:
So now I have a completely balanced signal chain from DAC to speaker.
Cheers!
Russ
The DAC is that your Opus? I'm also very interested in that one!
To have a a fully balanced signal from DAC to speaker would be great!
Count me in for two Sibling kits!
What kind of transformers are you using to power the Siblings?
Gr, Bastiaan
Hi Blimp,
I used the little 7VA dual 12V secondary amveco torroid we provide for kookaburra. It works just fine. I have also tried a little larger trafo, but it made no noticable improvement at all, so I will stick with the little amveco. I have one for each channel.
The DAC in the chain right now is a Cambridge DAC3 which is a great DAC, but I hope the Opus will be even better. I should know pretty soon.
Thanks for the interest.
I am currently selling my house, and building a new one, but very soon I will get these projects rolling with more speed. Also my new house is getting a custom made listening room, designed by me, for me. Very stoked about that. It will be a "golden cuboid" shaped room with double padded carpet, and a vent into a void(shop space) which is suppose to help eliminate some bass pressure. It will also have treated walls and ceiling as well as bass traps and such. Its been a long time coming. Having a house built to your specs is very very nice. Something I have never had before.
Cheers!
Russ
I used the little 7VA dual 12V secondary amveco torroid we provide for kookaburra. It works just fine. I have also tried a little larger trafo, but it made no noticable improvement at all, so I will stick with the little amveco. I have one for each channel.
The DAC in the chain right now is a Cambridge DAC3 which is a great DAC, but I hope the Opus will be even better.
I should know pretty soon.Thanks for the interest.
I am currently selling my house, and building a new one, but very soon I will get these projects rolling with more speed. Also my new house is getting a custom made listening room, designed by me, for me.
Very stoked about that. It will be a "golden cuboid" shaped room with double padded carpet, and a vent into a void(shop space) which is suppose to help eliminate some bass pressure. It will also have treated walls and ceiling as well as bass traps and such. Its been a long time coming. Having a house built to your specs is very very nice. Something I have never had before.Cheers!
Russ
Thanks for the info.
Building your own house with a listing room… Sounds great. I still have to talk my wife in to that one…..
I’m also very curious how the THS413X Sounds compared to my DRV134’s. The specs of the THS413X are way better!
What resistor value’s are you using in your proto-type? R(g) 374Ω and R(f) 750 Ω, to get a +6dB gain, with is more or less standard with balanced outputs.
I hope the kit comes with a AD8620. It’s very hard for me to get these nice op amp in the Netherlands.
Gr, Bastiaan
Building your own house with a listing room… Sounds great. I still have to talk my wife in to that one…..
I’m also very curious how the THS413X Sounds compared to my DRV134’s. The specs of the THS413X are way better!
What resistor value’s are you using in your proto-type? R(g) 374Ω and R(f) 750 Ω, to get a +6dB gain, with is more or less standard with balanced outputs.
I hope the kit comes with a AD8620. It’s very hard for me to get these nice op amp in the Netherlands.
Gr, Bastiaan
Blimp said:
Hello,
Yes, I was very fortunate to be able to pull this house thing off. I am thanking my lucky stars.
As for the THS4131 it is a totally different chip then the DRV, and it does sound excellent.
We will see about using the AD8620, it is a relatively expensive part. Other parts will work well too, but I agree, I would personally prefer the AD8620 over just about anything for this task.
I run the THS4131 at unity gain, the 6db gain is actually provided by the AD8620 in intrumentation mode. I used 390R resistors for RG and RF, as thats what I had on hand.
You could do it the other way too, run the AD8620 at unity gain and run the THS at 6db gain, which might actually be more optimal in terms of bandwidth since the THS4131 is a faster opamp.
I am very happy with the way I have mine right now, but I will likely play with some other values too.
Cheers!
Russ
Blimp said:
Hi Blimp,
Yes there is some news!
I am pretty well moved into my new home now, and have some time to work out a PCB design. The PCB design is the basis for this circuit as well as the driver PCB for a couple of symmetrical power amps. The PCB is multi purpose. You can use it has a high or low input impedance (essentially with or without input intrumentation amp) balanced line driver/preamp, or as the front end to a bridged symmetrical amp.
Anyway, the design is done. I am awaiting another PCB (MyRef Rev Cs) order from a new PCB manufacturer I am using. If those PCBs look good I will order a batch of these too, among other things...
I have a lot of projects in the mix right now, and they are all coming to a head at the same time.
Opus DAC/TXO(power amp)/TXS(power amp)/TS(preamp), plus power supplies for all above... Thats a lot of PCBs to finish up....
I better get to work!!! Cheers!
Russ
Banned
Joined 2002
Russ White said:
Hi Blimp,
Yes there is some news!
I am pretty well moved into my new home now, and have some time to work out a PCB design. The PCB design is the basis for this circuit as well as the driver PCB for a couple of symmetrical power amps. The PCB is multi purpose. You can use it has a high or low input impedance (essentially with or without input intrumentation amp) balanced line driver/preamp, or as the front end to a bridged symmetrical amp.
Anyway, the design is done. I am awaiting another PCB (MyRef Rev Cs) order from a new PCB manufacturer I am using. If those PCBs look good I will order a batch of these too, among other things...
I have a lot of projects in the mix right now, and they are all coming to a head at the same time.
Opus DAC/TXO(power amp)/TXS(power amp)/TS(preamp), plus power supplies for all above... Thats a lot of PCBs to finish up....
Cheers!
Russ
must post pictures too
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.