I don't have enough knowledge about this, but I think I find choke loaded amp has less flat distortion vs frequency when we actually connect the amp to the speaker. I guess speaker impedance plot may affect the distortion plot more with choke loaded amp. I saw flatter distortion plot with resistor loaded version in my case at least.
I dunno how to measure distortion without distortion analyzer but I have ears of more than 30 years experience. However LTSpice simulation agrees with me, regarding bass and inductance. More inductance more bass drop, HOWEVER, it works vice versa in highs.
What you earn with choke and results in lower distortion (again LTSpice agrees), is that you actually almost double the voltage. Higher voltage means lower distortion.
And another catch. You need actually more than 22000uF on output capacitor, since your speaker is going to reach at certain frequencies 4Ohm, even if nominal is 8.
i have listened to my OB multiway for almost 2years using minidsp and class ab amplifier. but finally i decided to finish bass reflex enclosure for Audio Nirvana classic 8
because this SIT has no cover, it is already in dusty condition. air compressor can't clean it up which hardened by moist
Fullrange + SIT : great combination
but honestly this combination does not gove too much excuse on bad recording where it's still fine on OB + class ab. i have to skip on bad music recording this time
additional 8dB bass boost from 40-80Hz on windows and corner placement really help the bass alot. no need to turn on subwoofer for music
because this SIT has no cover, it is already in dusty condition. air compressor can't clean it up which hardened by moist
Fullrange + SIT : great combination
but honestly this combination does not gove too much excuse on bad recording where it's still fine on OB + class ab. i have to skip on bad music recording this time
additional 8dB bass boost from 40-80Hz on windows and corner placement really help the bass alot. no need to turn on subwoofer for music
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Hi.
When you used the Hammond 195T5 did you change the bias compared to when you were using the 193V ? Or did you leave it the same?
I hope you don't mind me saying, as it may be obvious, but I would listen to what it sounded like and then make any heat sink changes required, even if it meant a low speed fan being added. (Not my ideal choice). (Though it may not be an amp for Greek summer use). (Luckily we don't get many hot sunny days in the U.K.) 
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193V is "sweeter" and has much more bass. Highs in quantity are lower but are much more "sweet" and "melting"... 195T5 has less bass but has very "bright" highs. In simulation the difference between the two are 0.1 db but you hear HUGE difference - go figure -.
However, 193V won't stand more than 3A and the thing is that:
If you plan to go lower than 94db sensitivity on speakers you are gonna need more than 3A bias, plus more Vd, because Ohm's law on 8 Ohm load requires that you need higher voltage than original scheme (there you have advantage over resistors load, because resistors cut the Vdd in half, chokes don't).
Increase in either voltage or bias current decreases distortion, so do what you can do based on your cooling solution, watching FET temperature, you should keep it below 70C.
GO and build this amp, you won't regret it. From start you ll notice how good this thing sounds and - because I am a purist - for the best amp I 've ever built. There is distortion in this build but i don't care - everything else is marvelous. Also bear in mind that SEs are unforgiving, prepare for it.
Regarding my build I am dissipating more than 500W right now, driving 89db speakers with ease. This replaced every other amp I have now, even the great Symphonic Line KRAFT monoblocks. Also distortion has gone really low. I have just ordered some Focal monster speakers to see what happens, till now they were on Dalis 7. I had to change from big Maggies I had for krafts, LAmp doesn't like much magneplanars
However, 193V won't stand more than 3A and the thing is that:
If you plan to go lower than 94db sensitivity on speakers you are gonna need more than 3A bias, plus more Vd, because Ohm's law on 8 Ohm load requires that you need higher voltage than original scheme (there you have advantage over resistors load, because resistors cut the Vdd in half, chokes don't).
Increase in either voltage or bias current decreases distortion, so do what you can do based on your cooling solution, watching FET temperature, you should keep it below 70C.
GO and build this amp, you won't regret it. From start you ll notice how good this thing sounds and - because I am a purist - for the best amp I 've ever built. There is distortion in this build but i don't care - everything else is marvelous. Also bear in mind that SEs are unforgiving, prepare for it.
Regarding my build I am dissipating more than 500W right now, driving 89db speakers with ease. This replaced every other amp I have now, even the great Symphonic Line KRAFT monoblocks. Also distortion has gone really low. I have just ordered some Focal monster speakers to see what happens, till now they were on Dalis 7. I had to change from big Maggies I had for krafts, LAmp doesn't like much magneplanars
jotom750, You'll see much lower distortion with larger choke at low frequency. LTSpice shows this and I confirmed this with several different chokes in real world. While I agree with alexopth1512, lower distortion does not always mean better sound, but you may want to research about it a little further before choosing chokes. In my experience, Hammond chokes are very good and they should work as they should be. Good luck.