As you said, nothing like mine.
But I have other problems for the next months, unfortunately.
Patrick
But I have other problems for the next months, unfortunately.
Patrick
We listened for quite some time tonight. I am pleased with the overall sound. I am tempted to reduce the overall gain, but it is nice to have it. Pitch black background. It gives the impression of improving bass response, both in amount and quality. Excellent imaging and soundstage presentation. Rewards a good recording. An unexpected positive is that it seems to have a very organic sound. Its a bad description, but you seem to really hear the character of instruments when listening to small ensembles. It is a bit ruthless. I would not recommend it for poor recordings. This listening session was with Oppo105 FE, J2 clone, and Satori monitors. Next week we will try wth LP12 and Sota Saphire tables.
At least nothing negative about the circuit. 🙂
You will probably find that the Hitachi TO220 devices has a much smoother frequency response than the Toshiba's, at least in simulation.
This you can verify by a simple 1kHz or 10kHz square wave.
Patrick
You will probably find that the Hitachi TO220 devices has a much smoother frequency response than the Toshiba's, at least in simulation.
This you can verify by a simple 1kHz or 10kHz square wave.
Patrick
Euvl,
That is interesting. Is that due to device capacitance? I am interested to hook it up and run test. It is not mine, so I will have to borrow it to do so, but I have to put a finish on the case, so I will have the opportunity. I am curious as to the phase of the distortion and whether it remains consistent through the audio band.
Andrew,
The Oppo has a passive volume control. As a matter of fact, I did not add volume control forthis reason. It is a pure gain stage, nothing else.
That is interesting. Is that due to device capacitance? I am interested to hook it up and run test. It is not mine, so I will have to borrow it to do so, but I have to put a finish on the case, so I will have the opportunity. I am curious as to the phase of the distortion and whether it remains consistent through the audio band.
Andrew,
The Oppo has a passive volume control. As a matter of fact, I did not add volume control forthis reason. It is a pure gain stage, nothing else.
Assumptions, Mr Patrick. It is my brother. It was a Christmas present. I tend to be slow, hence the 5 month delay. I can confirm this with a video at his house if you would like.
He wrote me this morning and said that he continues to be pleased. I may try changing the 200r load resistor to 100 to try to throw away more gain and reduce feedback, just to see what happens. He probably will tell me to leave it alone. I am going to try an SMD version with slightly different cascode and see how that turns out. Get either Susumu RG 5ppm or Vishay TNPU for the signal resistors. Make sure there not causing any issues🙄. It is a good circuit. I am sure your highly tweaked version with the laterals is impressive. I look forward to seeing it fleshed out.
200R load is a good one as you can use 100ohm twin-ax cables and 100R termination resistors as in a transmission line.
If you want to be able to drive lower load (like 100R), you really need other MOSFETs with a higher transconductance.
I do not see a need to do so at this stage.
If anything, you should first check square wave response.
Then try lateral FETs if you can get them. Beware of different pin assignment.
Patrick
If you want to be able to drive lower load (like 100R), you really need other MOSFETs with a higher transconductance.
I do not see a need to do so at this stage.
If anything, you should first check square wave response.
Then try lateral FETs if you can get them. Beware of different pin assignment.
Patrick
Buzzforb,
Please kindly contact MarkLai by PM regarding test PCB for speaker protection.
They will be ready end of the week.
Thanks,
Patrick
Please kindly contact MarkLai by PM regarding test PCB for speaker protection.
They will be ready end of the week.
Thanks,
Patrick
Thanks Buzz for sharing your experiences thus far.
It's nice seeing a little activity on this thread and seeing someone tinkering around with a F5X style preamp circuit, even though its not Patrick's fully fleshed out design. Looking forward to messing around with it myself when its ready, and I have a bit more time.
It's nice seeing a little activity on this thread and seeing someone tinkering around with a F5X style preamp circuit, even though its not Patrick's fully fleshed out design. Looking forward to messing around with it myself when its ready, and I have a bit more time.
So, Mr Patrick. I have an interesting experience to relate about my not so similar clone that I would like to get your opinion about.
Last night we had a good long listening session. Setup was Oppo105>Blue Jean Cable(Belden 1800F version)>(terrible clone)F5X preamp gain stage>DIY XLR cables>Terrible J2 clone> Satori Moniters
My brother wanted me to listen as he said the preamp had opened up some more and was pleased with where it seemed to be going in terms of performance. Only significant issue remaining was a slight graininess on the top end. I agreed about the graininess and argued that it was either tweeter cap or probably something we could tweak in the preamp. The graininess was present but was more of an issue if being extremely peculiar. The preamp sounded nice, but i felt that something was still missing. It was not WOWing me as much as I had expected. IT was good, very good, but not reference. I was bothered by my DIY XLR cables in the chain, as we had done a direct comparison with the Belden version when just playing the Oppo into the J2 and had noticed a difference. It was subtle, but present and audible. I had requested that my brother get an extra set of cables to replace the DIY version and he had done so, but instead of getting another set of Belden, he got two sets of Blue Jean Cables Canare version. We plugged in the Canare, replacing the DIY XLR cables in between the preamp and power amp and listened again. When the song was over, we both discussed the fact that there had been a noticable change in a very positive way. The sound opened up in a way that neither of us had expected. To be sure, we listened to a couple more songs, switching the cables bakc and forth. Without any doubt, the improvement was real. All in all, i was not surprised, as we are talking pro cables vs my cables. Even thought the sound had taken a big step in the right direction, we decided to try to switch the Canare for the Belden in between the Oppo and the Preamp. WOW. Talking about opening up. The sound coming from this rig now is reference level. I am talking about not building anymore and just listening. Synergy complete.
In an effort to be scientific in my approach, I went looking for the datasheets on the two cables. Here they are. Clearly the system liked the lower impednace cable. It made a SIGNIFICANT difference in the sound. Before it was good but constricted. I had no idea until the change, jsut how constricted it was. I was truly taken aback by the change. This preamp sounds so good now that I will be patiently waiting for your improved version.
http://www.canare.com/ProductItemDisplay.aspx?productItemID=53
http://www.belden.com/techdatas/metric/1800F.pdf
Last night we had a good long listening session. Setup was Oppo105>Blue Jean Cable(Belden 1800F version)>(terrible clone)F5X preamp gain stage>DIY XLR cables>Terrible J2 clone> Satori Moniters
My brother wanted me to listen as he said the preamp had opened up some more and was pleased with where it seemed to be going in terms of performance. Only significant issue remaining was a slight graininess on the top end. I agreed about the graininess and argued that it was either tweeter cap or probably something we could tweak in the preamp. The graininess was present but was more of an issue if being extremely peculiar. The preamp sounded nice, but i felt that something was still missing. It was not WOWing me as much as I had expected. IT was good, very good, but not reference. I was bothered by my DIY XLR cables in the chain, as we had done a direct comparison with the Belden version when just playing the Oppo into the J2 and had noticed a difference. It was subtle, but present and audible. I had requested that my brother get an extra set of cables to replace the DIY version and he had done so, but instead of getting another set of Belden, he got two sets of Blue Jean Cables Canare version. We plugged in the Canare, replacing the DIY XLR cables in between the preamp and power amp and listened again. When the song was over, we both discussed the fact that there had been a noticable change in a very positive way. The sound opened up in a way that neither of us had expected. To be sure, we listened to a couple more songs, switching the cables bakc and forth. Without any doubt, the improvement was real. All in all, i was not surprised, as we are talking pro cables vs my cables. Even thought the sound had taken a big step in the right direction, we decided to try to switch the Canare for the Belden in between the Oppo and the Preamp. WOW. Talking about opening up. The sound coming from this rig now is reference level. I am talking about not building anymore and just listening. Synergy complete.
In an effort to be scientific in my approach, I went looking for the datasheets on the two cables. Here they are. Clearly the system liked the lower impednace cable. It made a SIGNIFICANT difference in the sound. Before it was good but constricted. I had no idea until the change, jsut how constricted it was. I was truly taken aback by the change. This preamp sounds so good now that I will be patiently waiting for your improved version.
http://www.canare.com/ProductItemDisplay.aspx?productItemID=53
http://www.belden.com/techdatas/metric/1800F.pdf
Last edited:
Be careful man - if you say reference quality the Audio Police will come and demand that you have cables like this :Audio Cables, Stereo Cable, Speaker Cable, Roomtune, Acoustic Zen, Tara Labs Sales
But in all honesty, congrats on making the synergy happen! That's awesome!
What did it take, 6 amps? and a similar amount of preamps? 🙂
But in all honesty, congrats on making the synergy happen! That's awesome!
What did it take, 6 amps? and a similar amount of preamps? 🙂
Not my synergy, my brothers. In no way am I advocating fancy cables. I believe the answer is right there in the datasheets. Transmission line theory is most likely the explanation, but i just wanted to relay the experience. We are talking a distinguishable improvement in sound. Perhaps buffers on the outputs of both the OPPO and Preamp would negate this difference, but I cannot say with certainty
This is what I use myself, together with Lemo 2B connectors.
http://www.belden.com/techdatas/english/89207.pdf
No buffer needed for the preamp. It has enough driving capabilities.
Patrick
http://www.belden.com/techdatas/english/89207.pdf
No buffer needed for the preamp. It has enough driving capabilities.
Patrick
Last edited:
The capacitance seems to be a non issue, with the nominal impedance dominating performance. I say this only because the Canare have significantly higher capacitance(triple) but half the nominal impedance.