Hi guys,
You are discussing differences in sound between 01A, 26, 801 a.s.o.
But as these are all used in SE mode we know how important the influence of the power supply is.
Are the differences between these tubes so clear that no matter of which type of power supply is used the typical character of these tubes always comes out? And then we are not talking about the impact of all passive components apart from power supply capacitors for instance.
In other words, by choosing particular types of resistors, capacitors, chokes, transformers a.s.o. could not you tune for instance the sound of a 801A more in the direction of a 26?
You are discussing differences in sound between 01A, 26, 801 a.s.o.
But as these are all used in SE mode we know how important the influence of the power supply is.
Are the differences between these tubes so clear that no matter of which type of power supply is used the typical character of these tubes always comes out? And then we are not talking about the impact of all passive components apart from power supply capacitors for instance.
In other words, by choosing particular types of resistors, capacitors, chokes, transformers a.s.o. could not you tune for instance the sound of a 801A more in the direction of a 26?
Hmmm - there are always variables when switching between things. In my preamp breadboard I just switched the glow tubes for the HT and used the same bench supply at different voltage settings, so the PSU was basically the same.
I think originally I tried resistor loading on the plate and cathode - can't remember if the values changed. In that setup I really liked the 26 against the 01A and 10Y. I tried and discarded active plate loads and LED bias for the cathode. I tried an anode choke for the 26 and 01A and that was very good, so listened to the 26 like that for a while. Thanks to Thomas I converted to filament bias and that was a big step forward in sound.
I then got a Hammond 126C SE transformer, 10K:10K. Inductance wasn't enough for the 26 at 106H, and this is where the 10Y just streaked ahead. It sounded wonderful and I still have this front end. I then went over to a choke input filament supply and it sounded even better. I just got Rod's boards and want to try those after the choke - should be excellent.
So that was the journey. I have Lundahl LL1660/5mA which are perfect for the 26 so that might make a recovery and challenge the 10Y at some point, but the 10Y into the Hammond 126C is a tough act to beat - they just sound lovely together.
Andy
I think originally I tried resistor loading on the plate and cathode - can't remember if the values changed. In that setup I really liked the 26 against the 01A and 10Y. I tried and discarded active plate loads and LED bias for the cathode. I tried an anode choke for the 26 and 01A and that was very good, so listened to the 26 like that for a while. Thanks to Thomas I converted to filament bias and that was a big step forward in sound.
I then got a Hammond 126C SE transformer, 10K:10K. Inductance wasn't enough for the 26 at 106H, and this is where the 10Y just streaked ahead. It sounded wonderful and I still have this front end. I then went over to a choke input filament supply and it sounded even better. I just got Rod's boards and want to try those after the choke - should be excellent.
So that was the journey. I have Lundahl LL1660/5mA which are perfect for the 26 so that might make a recovery and challenge the 10Y at some point, but the 10Y into the Hammond 126C is a tough act to beat - they just sound lovely together.
Andy
Andy,
That' s what I meant, so many variables, and it seems that most of us pay so much attention to the tube because that's what we see and like. Tubes with their soft or bright glow, not to speak of the blue or purple glowing VR tubes....
The same seems to be the case with loudspeakers; we see the speaker, not the room acoustics..
Well this was more of a philosophical expression, but what I think is important is to keep an eye and ear on the whole thing, and not to focus on one particular subject while taking other things for granted.
That' s what I meant, so many variables, and it seems that most of us pay so much attention to the tube because that's what we see and like. Tubes with their soft or bright glow, not to speak of the blue or purple glowing VR tubes....
The same seems to be the case with loudspeakers; we see the speaker, not the room acoustics..
Well this was more of a philosophical expression, but what I think is important is to keep an eye and ear on the whole thing, and not to focus on one particular subject while taking other things for granted.
Hi!
All my designs are availble either assembled or as kits. I plan to publish the circuit. I just created a new blog site. I will use this to share my circuits. Nothing there yet, but stay tuned:
VinylSavor
Best regards
Thomas
All my designs are availble either assembled or as kits. I plan to publish the circuit. I just created a new blog site. I will use this to share my circuits. Nothing there yet, but stay tuned:
VinylSavor
Best regards
Thomas
Hi!
Yes, as in most of my designs there is a lot of iron
But People can also get a partial kit, for example if they want to use their own filament supply instead of my LCL approach with two chokes per tube.
As for cost we can exchange that per email.
Best regards
Thomas
Yes, as in most of my designs there is a lot of iron
But People can also get a partial kit, for example if they want to use their own filament supply instead of my LCL approach with two chokes per tube.
As for cost we can exchange that per email.
Best regards
Thomas
Hi Andy,
May I ask why you discarded active plate loads and LED bias? I have gone that route with my 2C22 preamp and the improvement over resistors is HUGE. I find the background to be much quieter, the bass to be stronger and the treble and mids to be clearer - the treble just floats in the room, in fact. I use a cascoded IXYS 10M45s CCS at 175V and 14.6mA on the plate and SiC Shottky diodes (3.4V bias) on the cathode for bias.
Did you get a different effect with your system?
Since we're talking tube types, has anyone compared the sound of #26 with 3a5. AIUI, #26 is a rather finicky little thoroubred that's not easy to design around. But the 3a5 is said to have a 'liquid sound,' and whatever that is, I think I want it! I also haven't been able to find the 26 online. Are they scarce?
***The difference between theory and practice is that in theory there is no difference between theory and practice, whereas in practice there is.***
Hi Magz -
I just didn't like the sound of sold state. The LEDs in the cathode had more midrange detail and substantially better bass. However, the overall sound was rather hard and coarse and ultimately tiring. It was a relief to put a good wirewound resistor in - and I've also been playing around with different wirewounds. Since I like smooth, smooth, smooth and am allergic to any harshness I also junked the active loads. They were perfectly good IXYS cascodes and again had more detail than a resistor, but the resistor was smoother, even though a more diffuse sound. The detail and focus came back with either a plate choke or a transformer. I've found that in general I'd take a choke or transformer over any active ss device. That's just me. Applies also to DC filament supplies which are really nice with choke input. Clearly others disagree, and ss does offer the best bass, no doubt of that, but not for me.
As for the 3a5, it's nice. Clear and detailed. Much to like, as also the case with the 1J6G. Useful in balanced circuits, but there are better options for single ended. For a start the 30 special is a better sound, then up again to the 01A, then at the top the 26 and 10y. I don't think it's difficult to find a 26. There are mountains of them about - it was understandably very popular.
Andy
I just didn't like the sound of sold state. The LEDs in the cathode had more midrange detail and substantially better bass. However, the overall sound was rather hard and coarse and ultimately tiring. It was a relief to put a good wirewound resistor in - and I've also been playing around with different wirewounds. Since I like smooth, smooth, smooth and am allergic to any harshness I also junked the active loads. They were perfectly good IXYS cascodes and again had more detail than a resistor, but the resistor was smoother, even though a more diffuse sound. The detail and focus came back with either a plate choke or a transformer. I've found that in general I'd take a choke or transformer over any active ss device. That's just me. Applies also to DC filament supplies which are really nice with choke input. Clearly others disagree, and ss does offer the best bass, no doubt of that, but not for me.
As for the 3a5, it's nice. Clear and detailed. Much to like, as also the case with the 1J6G. Useful in balanced circuits, but there are better options for single ended. For a start the 30 special is a better sound, then up again to the 01A, then at the top the 26 and 10y. I don't think it's difficult to find a 26. There are mountains of them about - it was understandably very popular.
Andy
OK, I guess we just like different things - I'm a detail freak, so the CCS and diodes really float my boat. Good luck on your quest for smoothness!
Andy, couple of questions. Did you give up on using active filtering on the filament as well? Secondly, have you by any chance tried 1S4 triode connected? It seems to have pretty nice curves, but I never had the chance to listen to it in a circuit.
Hi!
I'm a detail freak too
And you can combine it you can have a lot of detail, high resolution yet smooth sound. For me the ticket to that is thoriated tungsten DHTs with purely passive LCL filtered filaments
Best regards
Thomas
I'm a detail freak too
And you can combine it you can have a lot of detail, high resolution yet smooth sound. For me the ticket to that is thoriated tungsten DHTs with purely passive LCL filtered filaments
Best regards
Thomas
I agree with Thomas about thoriated filaments and chokes. On the other hand, I've had very good results with Rod Coleman's boards which are way ahead of all the other solid state regulators I've tried. I haven't solved what device to put after choke input yet - Rod's board is a contender but I haven't wired it up yet. Strangely after a choke the LM1084 as a voltage reg sounded better than as a current reg. Usually it's the other way around. I have a CMC to try out as well, but with the 10Y I run into problems with filament bias - the LM1084 shuts down. I'm going to try things with a 26 into a LL1660/5A which I'm just wiring up. I'll also try battery bias against filament bias.
Andy
Andy
Thanks Andy! I still wonder if the LT1084 can really maintain stability as a HV CCS. Look forward to your impressions of the new filament regulator Kits. The changes from the 2004 version, that you tried first, are small. But the new pass transistors, and a tweek to the CCS drive, mean the supply noise & ripple are rejected much better; ripple current levels down into the microamp level are quite easy to achieve. There's still some kits left, if any one wants to try this low-cost DIY solution - just click on my name & email for info.
hi guys
i am interested in building this 26 preamp. im a newbie. though this would be my 2nd diy preamp. i have zero knowledge on design though i try to learn from books.
any working schematic of this 26 preamp to share? would love a tips or two as well. or please point me to the direction.
thanks in adv.
erwin
i am interested in building this 26 preamp. im a newbie. though this would be my 2nd diy preamp. i have zero knowledge on design though i try to learn from books.
any working schematic of this 26 preamp to share? would love a tips or two as well. or please point me to the direction.
thanks in adv.
erwin
Hi Thomas, Thanks - they do seem to work well in all kinds of amps. They perform very differently to Chip-based regulators. My kits have much lower noise, and they are open-loop to the anode current - not possible with the LT108x/LM317 etc! In this way, they are like a passive solution.
I have some PDF application notes to show all the details of making the dc supply, how to choose (or make) a heatsink, photos of the build stages etc.... please click on my Name at the left; send me email or PM (including email address) and I can send the PDF documentation.
A single pair of regulators [heat 2 DHTs] cost GBP 23.00 for the 26 or 801A; a little extra for big Transmitters like the GM70. There are other versions available to operate as Filament bias, too even at 60V input - another advantage of discrete-transistor design!