Thanks. Crazy experience : your ears heard it but your brain can believe it, even after measurment ! I think I was in the midle of the Bias Sea for 24 hours and this reccording I knwo very well even just acoustical, saved my brain from an oyster syndrome !
Droler : it was after changing an extra cable in the filter and a // lytic in the bass impedance correction : a // C.R. with + & Gnd. ...after .... after having changing the capacitor... I finally measured my own loudspeaker...after having refurbishing two speakers for friends - caps-treble unit on the first, hence the low cost treble thread-
Well sometimes I ask myself about a top Fostex headphones and not big hifi again.... no I joke !
- both are needed !
Droler : it was after changing an extra cable in the filter and a // lytic in the bass impedance correction : a // C.R. with + & Gnd. ...after .... after having changing the capacitor... I finally measured my own loudspeaker...after having refurbishing two speakers for friends - caps-treble unit on the first, hence the low cost treble thread-
Well sometimes I ask myself about a top Fostex headphones and not big hifi again.... no I joke !
- both are needed !
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I have been asking around and doing research on active/electronic crossovers. The better ones with higher sound quality are very pricey. The pro style in the $200 US or less range are said to be not very good at high fidelity for home systems. So, for the near future; I'll stay with my passives. I should have most new X/O parts here today.
As much as I love the sound of 1st order crossovers; I think all HP here will end up being 2nd order. This allows for a higher SPL because the lower frequencies are obviously more greatly attenuated. Some low pass will also end up being 2nd order as well.
I do still have the MR16 Satori 6 in. mids and Dayton APA 150 amp out of the system for now. If, after all of this new X/O and driver re-arranging, I still don't get the desired results; the MR16 will re-join the P7PHD. I guess I could try the MR16 in the MW closed box with a 3rd order high pass. NOT what I would normally do but it does have a better sounding upper bass and lower mids than it's MW16 mid-woofer sibling. That is after all why they designed it in the first place. There are not that many design and build differences between the MR and MW but, as I said many times, the MW does bass better; the MR does mids better; it's just that simple.
As much as I love the sound of 1st order crossovers; I think all HP here will end up being 2nd order. This allows for a higher SPL because the lower frequencies are obviously more greatly attenuated. Some low pass will also end up being 2nd order as well.
I do still have the MR16 Satori 6 in. mids and Dayton APA 150 amp out of the system for now. If, after all of this new X/O and driver re-arranging, I still don't get the desired results; the MR16 will re-join the P7PHD. I guess I could try the MR16 in the MW closed box with a 3rd order high pass. NOT what I would normally do but it does have a better sounding upper bass and lower mids than it's MW16 mid-woofer sibling. That is after all why they designed it in the first place. There are not that many design and build differences between the MR and MW but, as I said many times, the MW does bass better; the MR does mids better; it's just that simple.
Hi, so the MR is better above 300 hz.
I believe active can be needed in a very complex multi way speakers with different specialised amps in front of a specific driver or a cheap system or for bass only as ears below circa 200 hz are less sensible to distorss, although upper harmonics remains and steep electronic filter for the bass may certainly helps. But it's also a tool to find the good cut-offs when someone has not many coils and caps as you already have. Then purchase the right real passive parts : time & monney saved. In this last scenario the Sure 20usd unit + it's usb programation module is certainly good enough for the task. Ok the noise floor number is maybe not sota but or the bass it maybe can stay without harms.
Not so long ago member Koifarm that makes ucd400 hypex tweak with input stage tube said the 400 usd DBX pro (so no the first 200 usd unit) has a good noise floor ratio, uch better than the first minidsp products.
Edit : I found the Scarletti like that in Europe : googled
Miserere: Works by Gregorio Allegri, Leonardo Leo, Giovanni Moro da Viadana & Francesco Scarlatti by Ensemble William Byrd, Graham O'Reilly on Amazon Music - Amazon.co.uk 20 british pounds used or brand-new in France : Miserere: Works by Gregorio Allegri, Leonardo Leo, Giovanni Moro da Viadana & Francesco Scarlatti de Ensemble William Byrd, Graham O'Reilly sur Amazon Music - Amazon.fr / Amazon.fr : choix d'achat : Miserere
Apple & Spotify stream it. I googled the words "
Miserere: Works by Gregorio Allegri, Leonardo Leo, Giovanni Moro da Viadana & Francesco Scarlatti
Amazon US has it just in mp3 upload, uh ! Apple & Spotify has it also but dunno the copression quality and has you have a cd players, I think you find it easier in disc. Maye you can purchase it with the identification number in a real shop, will be an import also though. Anyway, this is the best Allegri 's Miserere I never heard thanks this crystal clear voice, spatious reccording : when music has nothing to see with the resolution degree and sampling number - you don't hear in this reccording the singers breathings but who care ! . For e the Fink's album is a better easy use to get the speakers right, cause the Allegri is a live so very dependant of the venue acoustic and ingineer skills.
I believe active can be needed in a very complex multi way speakers with different specialised amps in front of a specific driver or a cheap system or for bass only as ears below circa 200 hz are less sensible to distorss, although upper harmonics remains and steep electronic filter for the bass may certainly helps. But it's also a tool to find the good cut-offs when someone has not many coils and caps as you already have. Then purchase the right real passive parts : time & monney saved. In this last scenario the Sure 20usd unit + it's usb programation module is certainly good enough for the task. Ok the noise floor number is maybe not sota but or the bass it maybe can stay without harms.
Not so long ago member Koifarm that makes ucd400 hypex tweak with input stage tube said the 400 usd DBX pro (so no the first 200 usd unit) has a good noise floor ratio, uch better than the first minidsp products.
Edit : I found the Scarletti like that in Europe : googled
Miserere: Works by Gregorio Allegri, Leonardo Leo, Giovanni Moro da Viadana & Francesco Scarlatti by Ensemble William Byrd, Graham O'Reilly on Amazon Music - Amazon.co.uk 20 british pounds used or brand-new in France : Miserere: Works by Gregorio Allegri, Leonardo Leo, Giovanni Moro da Viadana & Francesco Scarlatti de Ensemble William Byrd, Graham O'Reilly sur Amazon Music - Amazon.fr / Amazon.fr : choix d'achat : Miserere
Apple & Spotify stream it. I googled the words "
Miserere: Works by Gregorio Allegri, Leonardo Leo, Giovanni Moro da Viadana & Francesco Scarlatti
Amazon US has it just in mp3 upload, uh ! Apple & Spotify has it also but dunno the copression quality and has you have a cd players, I think you find it easier in disc. Maye you can purchase it with the identification number in a real shop, will be an import also though. Anyway, this is the best Allegri 's Miserere I never heard thanks this crystal clear voice, spatious reccording : when music has nothing to see with the resolution degree and sampling number
- you don't hear in this reccording the singers breathings but who care ! . For e the Fink's album is a better easy use to get the speakers right, cause the Allegri is a live so very dependant of the venue acoustic and ingineer skills.I saw the US Amazon MP3. I will search more myself. Maybe someone in Europe has a FLAC download CD or higher quality. I can be happy with Spotify or YouTube just for casual listening; I won't pay for MP3 quality; too low to pay for in my opinion. Vinyl LP would be great but probably no one has it!?? I don't want to spend 40 to 50 equivalent US dollars for a CD right now. COVID is getting much worse here again in the USA because people are being stupid and not wearing masks and not listening to the medical experts. That means, my Daughter, Girlfriend and others probably will not find any jobs anytime soon. So; sadly, I need to have a tighter budget. Maybe one or two more inductors or capacitors and that will be it for spending until things improve here.
Thanks for the links Diyiggy!
Thanks for the links Diyiggy!
Yep, we ringed the bell about cv-19 here for american continents for people to have a tactical time advance thanks to italians soon alerts for the world - Internet communities have an advance vs the press. Very odd, message was understood though too much often a sort of deny in the same time, even here I was called to move ctc daily information link I putted in my signature base line as a reminder.. that was uspsiting some people which was strange to me, some people want to believe to miracle but not facts. That also prove our nature is more in the moment that in the long term, physicaly, senses, hence our love of music : this is in the moment pleasure. Well I reassure you, same here more or less in CE, young people that have parents, grandparents, that also loose their job- here 2008 crisis sequels are still here- don't respect too much the safety distance. That's odd to me as a rational personn and liking people to be happy and being honnest in their relation to others... Very strange to me what happen. But the virus, seems to stupidity is even more contagious due to our nature to be in the moment/instant/instinct.
Going back to your design, I follow because the nice pedagogy behind the talk; Then the second bass section of the left speaker that worked again after fixing the cable filter soldering I have realized how much the bass can mask the medium readness when the room is too much excited : room modes, presurization?. My bass is cutting very low around 100hz.acoustical, tunned to 0.5 Qtc/35 hz f3, cabinet at half the safe distanciation spacing from the wall if I remember and sealed so not on the snail side of the bass. My room is circa 40 square meters and bass are Sd 8" driver equivalent, so nothing big... but bass second and third octave should not be heavy but light and tight, at least since 50/60 hz. I'm asking myself if it's not what you experiment liking more one SB16 over its specialised bass sibling... something thatmate better with the room perhaps. Try Arta for some measurments : very fast to start with vs REW. Try the last post of the Arta sticky here in multiway section with Hensolo very nice & short starting fast "how to".
Going back to your design, I follow because the nice pedagogy behind the talk; Then the second bass section of the left speaker that worked again after fixing the cable filter soldering I have realized how much the bass can mask the medium readness when the room is too much excited : room modes, presurization?. My bass is cutting very low around 100hz.acoustical, tunned to 0.5 Qtc/35 hz f3, cabinet at half the safe distanciation spacing from the wall if I remember and sealed so not on the snail side of the bass. My room is circa 40 square meters and bass are Sd 8" driver equivalent, so nothing big... but bass second and third octave should not be heavy but light and tight, at least since 50/60 hz. I'm asking myself if it's not what you experiment liking more one SB16 over its specialised bass sibling... something thatmate better with the room perhaps. Try Arta for some measurments : very fast to start with vs REW. Try the last post of the Arta sticky here in multiway section with Hensolo very nice & short starting fast "how to".
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I still have a shallow null at 60 Hz +/- 5 Hz or so. I may need to figure out the REW or ARTA next so I can determine WHY I have this. Since the woofer chamber has the Aperiodic flow resistor; I doubt that there is a weird out of phase cancellation inside the box (not ruled out though). I did block the vent; with a pure 60 Hz sine wave tone; blocking the vent made ZERO difference. I think it is a room mode. When doing test tones, sweeps, etc. it is quite obvious. When listening to music; I really don't notice it much at all so I could live with it if need be. As I keep saying; it is not a very big room and I have no where else to really put these woofer boxes that would fit well.
Sad news; I partly blew one of the MA Pluvia 7PHD FR drivers; TOO MUCH POWER (so I will now cross them HP, 2nd order at 600 to 700 Hz). I have a second pair of these; at least they are not very expensive. I will swap the pair as these come shipped as a matched pair. Each Mark Audio P7PHD pair is matched at their factory; a nice touch for something that only cost about $100 US per pair. (I will replace the second pair later; they are for a small kitchen system I'm not using now anyway).
Good news; most of my X/O parts arrived so I played around some and am now getting results good enough to keep me happy for some time!
Some fine tuning and finally measuring yet to come but the SB29 will have a 1st order LP at about 170 Hz. The Jantzen inductor :
( Jantzen Audio 5.6mH 14 AWG C-Coil Toroidal Inductor Crossover Coil )
is doing what it should do. Expensive but worth it here. There is only one winding layer around the toroid which is how the DCR is so incredibly low. Bass is "tight" and "quick". Translation: more accurate, less mushy or bloated than with the other two 15 mH coils I had in parallel. They are 18 AWG so even in parallel, the DCR is way higher than with the Jantzen. The slight increase in X/O freq. also is helping match the Satori HP better here as well.
The Satori MW16 (mid-woofer) will have a 2nd order HP at about 230 Hz (there is no "gap" between the 170 Hz and 230 Hz that I can hear; maybe I could measure something small here but they blend seamlessly so far as I can tell without proof by measurement).
I will keep the new 0.9 mH inductor on the MW16 for the 1st order LP. (This calculates to -3 dB at 700 Hz assuming exactly 4 Ohms). There is plenty of higher frequencies that very gradually get attenuated but that is working to my advantage here. I purposely do NOT want a Zobel or 2nd order here; the gradual roll-off is helping supplement the P7P just as it was when I was using the MR16 6 inch mid. The P7P as mentioned will be 2nd order HP 600 to 700 Hz and a 1st order LP on top about 4400 Hz. Before I had a 2nd order here but at a higher frequency. The 4400 Hz 1st order sounds more natural and has a better blend and match with the Fostex T90A. This may change slightly again after measuring but with piano, violins, etc.; the harmonics and overtones are rich and full but not too bright or "edgy"...Goldilocks..."just right"...I have tried hepa-litz, regular coil inductors here and now a flat foil type. I have noticed this elsewhere; when comparing these 3 types of inductors; the flat foil type gives a better bass even though that is a completely different part of the spectrum than the X/O. This is obvious on my other pair of Pluvias also. Different value, different box style, different amplifier, different listening environment. The flat foil inductor just lets more bass get through. It may just be DCR or it may be a combination of other things as well. Without very sophisticated measuring equipment; I doubt I'll be able to prove this. It really doesn't matter EXACTLY why to me though; there is a noticeable improvement; that's good enough for me!
Sad news; I partly blew one of the MA Pluvia 7PHD FR drivers; TOO MUCH POWER (so I will now cross them HP, 2nd order at 600 to 700 Hz). I have a second pair of these; at least they are not very expensive. I will swap the pair as these come shipped as a matched pair. Each Mark Audio P7PHD pair is matched at their factory; a nice touch for something that only cost about $100 US per pair. (I will replace the second pair later; they are for a small kitchen system I'm not using now anyway).
Good news; most of my X/O parts arrived so I played around some and am now getting results good enough to keep me happy for some time!
Some fine tuning and finally measuring yet to come but the SB29 will have a 1st order LP at about 170 Hz. The Jantzen inductor :
( Jantzen Audio 5.6mH 14 AWG C-Coil Toroidal Inductor Crossover Coil )
is doing what it should do. Expensive but worth it here. There is only one winding layer around the toroid which is how the DCR is so incredibly low. Bass is "tight" and "quick". Translation: more accurate, less mushy or bloated than with the other two 15 mH coils I had in parallel. They are 18 AWG so even in parallel, the DCR is way higher than with the Jantzen. The slight increase in X/O freq. also is helping match the Satori HP better here as well.
The Satori MW16 (mid-woofer) will have a 2nd order HP at about 230 Hz (there is no "gap" between the 170 Hz and 230 Hz that I can hear; maybe I could measure something small here but they blend seamlessly so far as I can tell without proof by measurement).
I will keep the new 0.9 mH inductor on the MW16 for the 1st order LP. (This calculates to -3 dB at 700 Hz assuming exactly 4 Ohms). There is plenty of higher frequencies that very gradually get attenuated but that is working to my advantage here. I purposely do NOT want a Zobel or 2nd order here; the gradual roll-off is helping supplement the P7P just as it was when I was using the MR16 6 inch mid. The P7P as mentioned will be 2nd order HP 600 to 700 Hz and a 1st order LP on top about 4400 Hz. Before I had a 2nd order here but at a higher frequency. The 4400 Hz 1st order sounds more natural and has a better blend and match with the Fostex T90A. This may change slightly again after measuring but with piano, violins, etc.; the harmonics and overtones are rich and full but not too bright or "edgy"...Goldilocks..."just right"...I have tried hepa-litz, regular coil inductors here and now a flat foil type. I have noticed this elsewhere; when comparing these 3 types of inductors; the flat foil type gives a better bass even though that is a completely different part of the spectrum than the X/O. This is obvious on my other pair of Pluvias also. Different value, different box style, different amplifier, different listening environment. The flat foil inductor just lets more bass get through. It may just be DCR or it may be a combination of other things as well. Without very sophisticated measuring equipment; I doubt I'll be able to prove this. It really doesn't matter EXACTLY why to me though; there is a noticeable improvement; that's good enough for me!
SO CLOSE! My last X/O parts are delayed in US mail; most likely due to COVID causing extra mailings and strain on the system.
I have the NAD on max output feeding the Fostex ST; ZERO strain; ZERO detectable distortion.
I have the Crown feeding the SB29 and MW16 pair also on max output; also ZERO strain or detectable distortion.
The Yamaha feeding the P7P is at 12 O'clock; "half" way up on the volume control; also; ZERO strain or detected distortion.
SO CLOSE!...
Have on a re-master CD of Herbie Hancock from the 70's; Head Hunters; a very familiar recording to me going back to High School and College years.
Head Hunters - Wikipedia
Takes me back for sure! I saw them live in probably 1973? Great times, great tunes...Funk/Rock Electronic/Acoustic FUSION..crossed many musical boundaries in those days!
I have the NAD on max output feeding the Fostex ST; ZERO strain; ZERO detectable distortion.
I have the Crown feeding the SB29 and MW16 pair also on max output; also ZERO strain or detectable distortion.
The Yamaha feeding the P7P is at 12 O'clock; "half" way up on the volume control; also; ZERO strain or detected distortion.
SO CLOSE!...
Have on a re-master CD of Herbie Hancock from the 70's; Head Hunters; a very familiar recording to me going back to High School and College years.
Head Hunters - Wikipedia
Takes me back for sure! I saw them live in probably 1973? Great times, great tunes...Funk/Rock Electronic/Acoustic FUSION..crossed many musical boundaries in those days!
Stanley Clarke - Wikipedia
Stanley Clarke debut album on CD player now. One of my references; NOT super High Fidelity but one of my most treasured and familiar recordings of all my time. I know EXACTLY what this is supposed to sound like. This is one of the recordings I took to Akihabara for the several hundred thousand dollar super high end stereo comparison weekend back in the Navy days. Some people like to say that no one can possible remember what something sounded like years or decades ago; I TOTALLY disagree with this! Maybe it is once again my musician and artistic side over taking my engineering and technician side. I know what I heard; how it sounded to me then; and I am convinced I haven't lost my touch in these things at all. Just; anything above 12 to 15 KHz is WAY beyond my HF range these days; other than that; I "still have it" as they say in these parts...
Stanley Clarke debut album on CD player now. One of my references; NOT super High Fidelity but one of my most treasured and familiar recordings of all my time. I know EXACTLY what this is supposed to sound like. This is one of the recordings I took to Akihabara for the several hundred thousand dollar super high end stereo comparison weekend back in the Navy days. Some people like to say that no one can possible remember what something sounded like years or decades ago; I TOTALLY disagree with this! Maybe it is once again my musician and artistic side over taking my engineering and technician side. I know what I heard; how it sounded to me then; and I am convinced I haven't lost my touch in these things at all. Just; anything above 12 to 15 KHz is WAY beyond my HF range these days; other than that; I "still have it" as they say in these parts...
As far you're not talking about Dian Krall I will follow the thread ... One day I was buying vegetables at the supermarket and they was playing Diana Krall... it was so boring I was doing a race with the vegetables at the flatter brain graphs ... almost risked the coma myself ! . A good buddy of mine said one day a lift refused to work as they was playing D. Krall...
... One day I was buying vegetables at the supermarket and they was playing Diana Krall... it was so boring I was doing a race with the vegetables at the flatter brain graphs ... almost risked the coma myself ! . A good buddy of mine said one day a lift refused to work as they was playing D. Krall...yes, but I have her voice committed to memory; I don't like it usually but it does bring out the absolute worst in high mid range and low treble. I use it because it annoys me; if I try to over fix her voice; it usually means I have gone too far. It might be her voice; her microphone, her recording studio or engineers; probably a combination. My Sister in Law sings jazz; WAY better voice; WAY better control....sadly, no "good" recordings thus far....
I use Musica Nuda Live at FIP where her voice clips the mic at many moments making my ears drill. I setup my NOS dacs just to erase this extra energy , I check with triangle reccordings and K Jarett piano that climbs often high for instance and he plays a lot at the right side of the piano...more metalic that common Steinways he don t like too much if I read correctly.
With Krall my Brain clips not because a mic but because she is borring for my tastes, the only reccord from her I own is well recorded and clean...but something clean and clinical...no jazz...supermarket music... A little like Yu Sun Na, the korean woman, stunning voice and reccording but jazz feeling is hardly readable.
...
With Krall my Brain clips not because a mic but because she is borring for my tastes, the only reccord from her I own is well recorded and clean...but something clean and clinical...no jazz...supermarket music... A little like Yu Sun Na, the korean woman, stunning voice and reccording but jazz feeling is hardly readable.
...
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Ok, FINALLY!
I have all of my X/O parts. Once I get the measuring system figured all out and going; I'll try to see what is REALLY going on.
The SB29 is 1st order LP at 170 Hz
The MW16 is 2nd order HP at 250 Hz and 1st order LP at 700 Hz
The P7PHD is 2nd order HP at 700 Hz and 1st order LP at 4400 Hz
The T90A is 2nd order HP; -3 at about 19KHz. This gives me a treble boost starting at about 8 KHz. This is 2 or 3 dB above the P7P at 8 KHz rapidly rising to a max output of 10 dB above nom. at 10 KHz and about 17 dB above nom. at 20 KHz. Just past 12 KHz; my HF hearing drops like a brickwall filter!
So far, so good; more details later...
Mostly concentrating on acoustic jazz right now; my best recordings in this genre I have on CD. The turntable can't be used right now. The stereo rack is on casters so I can move it around. I have it turned sideways so I can access all of the input and speaker jacks. In this position; the TT shelf is WAY out of level; no way to level it without putting the rack back into place.
I have all of my X/O parts. Once I get the measuring system figured all out and going; I'll try to see what is REALLY going on.
The SB29 is 1st order LP at 170 Hz
The MW16 is 2nd order HP at 250 Hz and 1st order LP at 700 Hz
The P7PHD is 2nd order HP at 700 Hz and 1st order LP at 4400 Hz
The T90A is 2nd order HP; -3 at about 19KHz. This gives me a treble boost starting at about 8 KHz. This is 2 or 3 dB above the P7P at 8 KHz rapidly rising to a max output of 10 dB above nom. at 10 KHz and about 17 dB above nom. at 20 KHz. Just past 12 KHz; my HF hearing drops like a brickwall filter!
So far, so good; more details later...
Mostly concentrating on acoustic jazz right now; my best recordings in this genre I have on CD. The turntable can't be used right now. The stereo rack is on casters so I can move it around. I have it turned sideways so I can access all of the input and speaker jacks. In this position; the TT shelf is WAY out of level; no way to level it without putting the rack back into place.
Now enjoying FLAC files from various classical music stores online located in Europe. I was having major issues at first. The download files are very large and need to be extracted (UN-ZIP). I finally realized my anti-virus and other protection software was preventing full downloads or un-zipping. I temporarily un-installed these until all downloads were completed. Then I re-installed them. I recently got an external HDD hard drive to store photos and FLAC music files on. I wanted SSD but the prices are still very high for solid state. I have 5 TB; that should be plenty! I was warned to un plug it when not in active use though. This will hopefully make it last much longer!
I'm taking a temporary break from building the other woofer box. My X/O configuration is final for the moment; mostly still using clip leads until I do testing. I think I will save the REW and M-Audio measurements until the other side is completed. Heat index in the middle of the USA today is 110 deg F (>43 deg C)!!!
Not the day for using a big Class A amp...
The secret of datas is always to have a copy you putt elswhere than your home.
And if it is not in a Microsoft Windows on c:/ where the OS is then the 5 To disk will not swapp all the time as it should - Microsoft behavior whatever the RAM you have and the setups you make. I would not worry myself in that data library managment context before 6 years of daily use.
The secret of datas is always to have a copy you putt elswhere than your home.
And if it is not in a Microsoft Windows on c:/ where the OS is then the 5 To disk will not swapp all the time as it should - Microsoft behavior whatever the RAM you have and the setups you make. I would not worry myself in that data library managment context before 6 years of daily use.
Before I figured out what was going on; it forced me to clean out all of my old files and delete programs I didn't need or use anymore. My RAM is about at half; plenty of room. I do have a solid state hard drive built in but I hope to build up a good FLAC library so I decided to get the external drive for that.
I am listening to F J Haydn these days; his chamber music mostly. Have you heard of the Baryton? It looks similar to a Viola da Gamba. Haydn wrote many pieces for this bass string instrument. I like the tone.
Baryton trios (Haydn - Wikipedia)
I remember my Uncles, Father, GrandFather all had vacuum tube amplifiers; some pure class A...hot hot hot!!!
I only pushed the new Crown hard enough one time for the fans to turn on; it is class A/B. All of my amps are A/B except the sub plate amp is class D.
I am listening to F J Haydn these days; his chamber music mostly. Have you heard of the Baryton? It looks similar to a Viola da Gamba. Haydn wrote many pieces for this bass string instrument. I like the tone.
Baryton trios (Haydn - Wikipedia)
I remember my Uncles, Father, GrandFather all had vacuum tube amplifiers; some pure class A...hot hot hot!!!
I only pushed the new Crown hard enough one time for the fans to turn on; it is class A/B. All of my amps are A/B except the sub plate amp is class D.