joessportster Posted June 29, 2014 Share Posted June 29, 2014 I have never been a big Classical & Jazz fan, there are a few songs I like very much but for the most part a couple minutes is all I could stomach I have had Diana Krall, Glad Rag Doll, for months on my pc and never could get past the first song She just drove me nuts For what ever reason with the Kenzie Headphone amp in the system I find myself enjoying the album. I doubt it will ever be a go to album for me but at least I can set through and enjoy it, I am also finding Classical more enjoyable I find the Kenzie absolutely needs minimum 1/2 hour warm up and it really opens up. It is now reminding me more and more why I was such a SET fanatic.....................I wish I had the vocabulary to write what my ears hear with this amp Color me HAPPY with this amp........................I Honestly did not want to like it as I was so happy with the SE84, I told my wife right off the bat, I was going to give it a short listen and box it up Yea Right, it has a new permanent home...................... (sorry Dean but I am not letting this out of the set-up, I can send you the SE84 again though ) Something else I find, this amp does not get hot, it is barely warm after 4 straight hours of listening and 1/2 hour of warm up with the phones just hanging off the shelf If you have efficient horns and ever thought about setting up a 2 way bi-amp system I urge you to give the Kenzie a shot at the top end.......................It honestly just SINGS Quote Link to comment Share on other sites More sharing options...
Schu Posted June 29, 2014 Share Posted June 29, 2014 I think... and correct me if I am wrong, that certain set ups seem to produce better results with certain music modes. for instance, my current set up kills at Jazz, Classical or orchestrated music... I mean it's clear, completely dimensional and floats in the air... when I put on grungy rock, it's painful to listen to even though it is clearer and well separated. why is this? Hell, I dont know... but I know I do like it. Quote Link to comment Share on other sites More sharing options...
joessportster Posted June 29, 2014 Author Share Posted June 29, 2014 I have found this to be true as well in most set ups, I dont do ROCK very often anymore....................mainly Acoustic, some indie, some folk, and some classic rock When I get in a mood (not necessarily a good mood) I listen to some dark harder rock..............never been into metal or anything harder so that does not become an issue............I am finding most of my tastes are performing very well on the Kenzie Now I am wondering how the sound will translate to open air speakers / horns.......................I hope someone here on the forum gets one and reports there findings.............................. Quote Link to comment Share on other sites More sharing options...
Deang Posted June 29, 2014 Share Posted June 29, 2014 I think... and correct me if I am wrong, that certain set ups seem to produce better results with certain music modes. for instance, my current set up kills at Jazz, Classical or orchestrated music... I mean it's clear, completely dimensional and floats in the air... when I put on grungy rock, it's painful to listen to even though it is clearer and well separated. why is this? Hell, I dont know... but I know I do like it. Garbage in = garbage out. Music with a lot compression only sounds good at low volume levels -- one of the reasons I went to quasi-nearfield. It probably saved my ears. Quote Link to comment Share on other sites More sharing options...
Schu Posted June 29, 2014 Share Posted June 29, 2014 Garbage in = garbage out. Music with a lot compression only sounds good at low volume levels -- one of the reasons I went to quasi-nearfield. It probably saved my ears. Quote Link to comment Share on other sites More sharing options...
joessportster Posted June 29, 2014 Author Share Posted June 29, 2014 Agree garbage in = garbage out however I am talking about good quality recordings of genera specific recordings that I have found unbearable in most setups some of them I considered very good setups The Kenzie just (for what ever reason) makes it possible for me to listen and enjoy Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted June 29, 2014 Share Posted June 29, 2014 Joe, what makes the recordings you mentioned unlistenable on amps other than the 1626 unit? Even Bob Danielak, in his original article about the "Darling," admitted that the tube is run fairly high in 2nd harmonic output (which is known to sweeten irritating recordings since it's musically consonant) if I recall correctly. That may explain why the amp is imparting pleasing sound qualities. Perhaps Justin can reveal the operating parameters of the tubes (plate voltage/current, grid bias, opt primary impedance, etc.) which will allow the distortion to be calculated. I'm curious! Remember also that the amount of power you're using when listening, and the variations in impedance of your headphones, will profoundly affect the resulting sound (more power=higher distortion; higher load impedance to the tube=lower distortion). So, it's likely a combination of factors which is generating such a pleasing result. With speakers, or different phones, the results may be totally different. Enjoy!Maynard Quote Link to comment Share on other sites More sharing options...
justinsweber Posted June 30, 2014 Share Posted June 30, 2014 Hey everyone. I took the weekend off and went to Lake Havasu so I’m pretty useless for details at the moment. Plate and grid are pretty close to Darling spec and definitely within the tube data specs. The real changes came with increases in cap filtering. That said the Kenzie headphone amp was my attempt to take a well know super easy circuit and see if good transformers could convert to a headphone amp well enough. I didn’t want to use the tried and true route of voltage dividing networks. The version we use uses a 5k primary with 32ohm and 600ohm secondarys. In general I try to run higher impedances to reduce distortion… for SE setups this will be 5k. (As an aside, I gave in on an amp I’m building for myself and ordered some 4.2K primaries to see if it will yield more power without significantly increasing distortion.) Quote Link to comment Share on other sites More sharing options...
Ski Bum Posted June 30, 2014 Share Posted June 30, 2014 I am wondering how the sound will translate to open air speakers / horns.... It will translate, although each individual pairing will result in it's own interpretation. Generally speaking, power and bass are SET's weaknesses when driving speakers. SETs tend to pair very well with cd/horns and full range drivers, so the idea of bi-amping you mentioned in your first post is on target. I'm not at all surprised you like the SETs with jazz. SETs just kill it on certain sounds, particularly vocals, the decay of cymbals, etc. Quote Link to comment Share on other sites More sharing options...
Schu Posted June 30, 2014 Share Posted June 30, 2014 Xylophones... and some horn movements are pure magic! With SS, you should hear Taiko drums... specially the big bertha drum. you can literally hear the membrane moving as the frequency slowly rolls off and decays. Quote Link to comment Share on other sites More sharing options...
justinsweber Posted June 30, 2014 Share Posted June 30, 2014 One interesting twist I've been mulling over is SS rectification with SETs vs Tube. Most of my amps are built with SS rectification for reliability, faster transients, bit more bass authority. That said, my fav SET amps are tube rectified... just my personal preference. Some people are capacitor junkies… I suppose I’m an iron junkie. Quote Link to comment Share on other sites More sharing options...
joessportster Posted June 30, 2014 Author Share Posted June 30, 2014 Joe, what makes the recordings you mentioned unlistenable on amps other than the 1626 unit? Even Bob Danielak, in his original article about the "Darling," admitted that the tube is run fairly high in 2nd harmonic output (which is known to sweeten irritating recordings since it's musically consonant) if I recall correctly. That may explain why the amp is imparting pleasing sound qualities. Perhaps Justin can reveal the operating parameters of the tubes (plate voltage/current, grid bias, opt primary impedance, etc.) which will allow the distortion to be calculated. I'm curious! Remember also that the amount of power you're using when listening, and the variations in impedance of your headphones, will profoundly affect the resulting sound (more power=higher distortion; higher load impedance to the tube=lower distortion). So, it's likely a combination of factors which is generating such a pleasing result. With speakers, or different phones, the results may be totally different. Enjoy! Maynard Hey Maynard I think the main reason is I just never got into jazz on the whole. I like a lot of different music, Jazz has never been one of them. I can appreciate the music and the talent that makes it I believe the fact that the Kenzie presents music the way it does keeps me interested enough to keep listening.....................The vocals are so varied and lifelike ( I can hear all the spittle, pops and clicks etc..in the artist mouth / voice) I can hear how the tone changes, the highs and lows piano, acoustic guitar,& bass are also lifelike with great pluck and resonance a lot of amps don't seem to get the body of the instrument. One big surprise with this amp is the solidity of the bass, it goes very low and has great definition tight & impactful (I would bet this has a lot to do with the headphones) What ever the reasons I am happy to have more musical selection to listen to now Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted June 30, 2014 Share Posted June 30, 2014 Thanks for the elaboration Justin and Joe. Joe, you are totally correct when you say that you're just happy to have more to listen to regardless of why! That's the real essence of audio and also why synergy between the amp and either speakers or headphones is so important. Yes, the 1626 is one of those interesting tubes which delivers a high level of unexpected performance. Danielak's original design specified a supply voltage of 265 but didn't mention the dc resistance of the output transformer primary, the quiescent plate current, or grid bias. So, to run some calculations, I assumed that the tube "sees" 250V plate to cathode. Because of the very low plate dissipation of only 5 watts, the quiescent current (i.e. when no signal is present) has to be very low- in my modeling, 18 ma. To achieve the assumed bias of -34V would require a cathode resistor of approx. 1900 ohms (in Danielak's design it was 1000 ohms which makes me scratch my head a bit). Anyway, using the numbers above, the calculated power output is about 940 milliwatts which correlates well with Danielak's claimed output of 750 mw (remember, the output xfmr is not 100% efficient). But, at full power out, the 2nd harmonic distortion is almost 16%! This, of course, will decrease in proportion to the power. So if one is listening at only 50-100 mw, the distortion should be reasonably low. I'm throwing this out there in case anyone has a CAD program which can run this tube's parameters with greater accuracy. The bottom line is that it is not surprising that the Darling variants seem to sound so good, assuming that one likes the trademark SET presentation. Perhaps Mark, if he's following this, can explain why somewhat higher levels of 2nd harmonic distortion seem to enlarge and deepen the soundstage as well as making music seem so much more involving. Justin, if it won't violate any proprietary concerns, can you disclose the actual operating parameters that you are using? I'm wondering how close they are to what I modeled. As far as tube vs. SS rectifiers in flea power amps are concerned, the dc current variations from zero signal to full output are so low that it shouldn't matter what is used. From a cost standpoint, it doesn't make sense to add another tube and socket. Also, why draw more current from the power xfmr which will only make it run warmer? Joe says that the amp is cool after hours of use. I wouldn't mess with that! And going to an output xfmr with a 4.2k impedance vs the current 5k isn't likely to make any difference at all in regard to power or distortion. With SETs, there's too much "forgiveness" for 800 ohms to mean much. I've attached the plate curves for the tube in case any of the other amp enthusiasts want to look them over. Isn't this a fun hobby??? All the best.....Maynard Quote Link to comment Share on other sites More sharing options...
Deang Posted June 30, 2014 Share Posted June 30, 2014 Great posts Maynard. I don't understand everything you're talking about it, but I understand enough to make sense of it -- and that's quite an accomplishment! Quote Link to comment Share on other sites More sharing options...
justinsweber Posted July 1, 2014 Share Posted July 1, 2014 Specs: -1db 20 Hz to 10 kHz @ 200 mW, or -3db 11.3 Hz to 20 kHz, less than 5 mV of noise at idle. RMS was 200mW with the 32ohm tap @ 1000Khz. 250v to the plates, ~245-250v B+ Hope this helps... no real secret sause, but our attempts at clean builds :-). Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted July 1, 2014 Share Posted July 1, 2014 Sorry about the technical stuff Dean. Lacking Mark's eloquence to explain concepts using words (and he is a master of that!), I have to resort to numbers at times! Justin, thanks for providing the frequency response info. The rolloff above 10 kHz may, in part, explain some of Joe's satisfaction with the sound when listening to problematic recordings. Personally, if I can keep an amp fairly flat out to 10-12 kHz I'm quite satisfied, and actually prefer the sound of such amps to those with a more extended high frequency response. Interestingly, most of the guys I work with feel the same way which is why my "ear bleed filter" has been so popular. It allows the response to be shaped for as much as 12 db of decrease at 20 kHz. Whether this is a function of all of us being a bit on the "older side," is unknown. An experiment which you may find useful, especially if you have one on hand, is to try an opt with a 10k primary impedance. It will drop the power a little, but also cut the distortion. And, as you have found out, clean builds are essential for great sound and quiet operation! Keep up the good work!!! Maynard Quote Link to comment Share on other sites More sharing options...
joessportster Posted July 1, 2014 Author Share Posted July 1, 2014 Maynard unlike dean I did not understand most of that Justin so 3 db of roll off after 11.3 Khz all the way out to 20Khz (in lay terms not quite as loud from 11.3 to 20 Khz correct??), 3db does not sound like much loss maybe just enough to take the harsh off. I dont feel like I have lost any extension going from the SE84 to the Kenzie I think you are correct Maynard about my reasons for preferring SET, My ears / brain cannot handle bright / strident amps or speakers. Quote Link to comment Share on other sites More sharing options...
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