Has anyone tried a combination of choke and CCS ? Any experience on this ?
Example: I am using differential pairs, so there are some cascoded ccs...but to be honest I am always curious/cautious wether I can hear now the silicon in my tube amp...so isolating the sound effect of the transistors by connecting a choke in between the cathode and the ccs ?
...some people reported as well a positive effect by connecting a choke after the last capacitor of the psu and the Anodes...which would be another example to use a choke to isolate the actual amp from the support circuits...
Example: I am using differential pairs, so there are some cascoded ccs...but to be honest I am always curious/cautious wether I can hear now the silicon in my tube amp...so isolating the sound effect of the transistors by connecting a choke in between the cathode and the ccs ?
...some people reported as well a positive effect by connecting a choke after the last capacitor of the psu and the Anodes...which would be another example to use a choke to isolate the actual amp from the support circuits...
But if you use choke, why do you need CCS?
Choke has one important advantage over CCS as a load: instead of hogging B+ voltage like CCS does, it virtually doubles B+. This is a very important advantage at high output signal voltage. CCS's only advantage over choke is cheapness.
In New York, when they describe something useless, they say "This plus token gives you a ride on Metro".
Choke has one important advantage over CCS as a load: instead of hogging B+ voltage like CCS does, it virtually doubles B+. This is a very important advantage at high output signal voltage. CCS's only advantage over choke is cheapness.
In New York, when they describe something useless, they say "This plus token gives you a ride on Metro".
Last edited:
Well, that is my point: Get the impedance advantage of the ccs like mega or giga ohms, which a choke alone does not offer, with the advantage of the choke storing energy and being a passive component, which may sound superior as it is more neutral and isolating solid state stuff or caps from the circuit...both together would give you the advantage of both, no ?
CCS excels with high mu tubes, where its mega- and gigaohm impedance is useful. To add a choke between 12AX7 and CCS, the choke needs very high inductance to make a difference. The largest I have seen, 600 H @ 1 mA, has about 75 K impedance at 20 Hz. It will definitely block transistor harshness (if any) at high frequencies.
Plate choke is good for tubes with Rp<10 K. Such tubes don't need megaohm loads. Except at the lowest frequencies, choke alone offers near horizontal load line; a couple of degrees of tilt make little difference.
That is a bit my setting currently: two 4p1l as LTP with an amorphous OPT and a CCS from Kevin C. in the tail (cascoded). The idea was: what about a choke between the cathodes and the ccS...
To get a bit back to the topic: My amorphous OPT in this line stage can sound onbelieveable liquid with a breathtaking resolution. ... but ... my impression is that it needs a break-in-time. Meaning: When I do not use my system fror a week when I am on travel: It needs again a period of at least 12hours to sound as good as the week before. Is this only my impression or is this a feature of amorphous ?
To get a bit back to the topic: My amorphous OPT in this line stage can sound onbelieveable liquid with a breathtaking resolution. ... but ... my impression is that it needs a break-in-time. Meaning: When I do not use my system fror a week when I am on travel: It needs again a period of at least 12hours to sound as good as the week before. Is this only my impression or is this a feature of amorphous ?
I have an amorphous OPT for my PSE output stage which took me a while to get used to. More detail and clarity but at the expense of what I perceived as a rather brittle treble. I did finally get used to it but when I swapped in some O'Netics OPTs for a while I again found the sound rather brittle going back to amorphous. So could be break-in but could also be a psycho-acoustic phenomenon. Or maybe a bit of both.
My current thinking is to go "smooth" in the OPT - I'm liking the O'Netics. And to go "clarity" in the driver stage so I'm feeding the maximum clarity into the output stage. I don't have an amorphous plate choke but I'm considering it for the 10Y driver stage I'm now using. But I have to say I'm pretty pleased with my two 126C in series right now, so I'm not rushing. But it is something I want to try in either amorphous or nickel.
My current thinking is to go "smooth" in the OPT - I'm liking the O'Netics. And to go "clarity" in the driver stage so I'm feeding the maximum clarity into the output stage. I don't have an amorphous plate choke but I'm considering it for the 10Y driver stage I'm now using. But I have to say I'm pretty pleased with my two 126C in series right now, so I'm not rushing. But it is something I want to try in either amorphous or nickel.
I don't know which vintage K&K CCS you have is, but if it doesn't have the IXYS 8N50D2 on the bottom then it is very worthwhile to replace. Also, gains can be made by NOT mounting the bottom MOSFET on the heat sink. The added capacitance that mounting both devices on the heatsink defeats the high impedance of the CCS at high frequencies.
When it comes to Lundahl amorphous core transformers and plate chokes, I count 18 in my system from phono input to speaker out. They can take a long time to fully "break in". As far as brittleness after break-in, some of that could be an issue of "shoot the messenger". They are very transparent and revealing and that can be a double edged sword.
Smile...I have build this and while we write, I just converted back my PSU to my amorphous chokes instead of a CCS fed OD3/shunt reg. Exactly as you said to gain clarity and detail. Ae50 here in the forum provided me excellent amorphous chokes on amcc160 core which outperformed anything I got my fingers on sofar....they are expensive, but unbelievable good.
If I may contribute a little here I have built and listened to a few SE amps over the years and have the human ear is capable of 20Hz to 20 KHz a little more for some especially the young. M3 Double C cores easily do 20-20 -1db as can M6 M19 and Amorphous with large enough cores as they tend to saturate quite quickly with DC standing currents Most of these materials interleaved well extend upto 40Khz at 1 watt -3dB and the M19 and M3 go down to 10Hz at -1dB with enough metal.
The real issue is they all have a particular tonality across the audible range and each of us has to make up our minds what suits us . For a long time I liked Electra- Print M19, then custom made M3 and now Amorphous double C cores seem to have quite a magic sound in the all important midrange.
I think most DIYers would be happy with M6 and most commercial producers use M6 as bang for the buck its hard to beat . Having said that I have had custom made Amorphous Double C cores made for a SE EL509 on the bench with a separate CFB winding on the secondary , seems a bit more of an elegant way to deal with that particular tube and look forward to hearing it after the SE6A3 with M3 cores.
The real issue is they all have a particular tonality across the audible range and each of us has to make up our minds what suits us . For a long time I liked Electra- Print M19, then custom made M3 and now Amorphous double C cores seem to have quite a magic sound in the all important midrange.
I think most DIYers would be happy with M6 and most commercial producers use M6 as bang for the buck its hard to beat . Having said that I have had custom made Amorphous Double C cores made for a SE EL509 on the bench with a separate CFB winding on the secondary , seems a bit more of an elegant way to deal with that particular tube and look forward to hearing it after the SE6A3 with M3 cores.
Last edited by a moderator:
Great postings ! if I may add ....Amorphous cores saturate more quickly than M6 & M3 so you will need much more metal for good bass response . M19 that Electra-Print use sound great as do M6 from Magnequest, HiB from Japan Hashimoto, ISO (Tango) Radiometal from Audio Note UK and Amorphous from Monolith ( very expensive ) or not so expensive from NP Acoustics which are very good.
I have built a number of amps with most of these metals and in the end I believe you have to trust your ears as to which suits you best . If they cover the actual audio frequencies the Human ear can hear say 20Hz to 20Khz at -1db and 10hz to 40kHz at -3dB allowing for freq extension and overtones to creep back down the spectrum into the audible range you have covered off what is needed.
Most published specs for transformer producers are not in active amplifiers so expect quite a bit less frequency response once installed into your active circuit . Each of these metal bases has a slightly different sonic signature and the most expensive Amorphous or Nanocrystalline brightness may not suit you . Most commercial designs on the Market use bog standard M6 EI cores to great effect, so a DIY'er has the opportunity to go well beyond this level.
Bang for the buck Jacks M19's are very hard to beat, NP Acoustics Amorphous are excellent for the money and ISO (Tango) still edge out Hashimoto IMHO in terms of low insertion loss and clarity....happy hunting
I have built a number of amps with most of these metals and in the end I believe you have to trust your ears as to which suits you best . If they cover the actual audio frequencies the Human ear can hear say 20Hz to 20Khz at -1db and 10hz to 40kHz at -3dB allowing for freq extension and overtones to creep back down the spectrum into the audible range you have covered off what is needed.
Most published specs for transformer producers are not in active amplifiers so expect quite a bit less frequency response once installed into your active circuit . Each of these metal bases has a slightly different sonic signature and the most expensive Amorphous or Nanocrystalline brightness may not suit you . Most commercial designs on the Market use bog standard M6 EI cores to great effect, so a DIY'er has the opportunity to go well beyond this level.
Bang for the buck Jacks M19's are very hard to beat, NP Acoustics Amorphous are excellent for the money and ISO (Tango) still edge out Hashimoto IMHO in terms of low insertion loss and clarity....happy hunting
Last edited by a moderator:
