|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
75.80.175.57
Where do we stand these days in terms of a linear sounding, current production KT88 without excessive upper-bass/lower-mid bloat?
From recent posts by Mendel and Nunki, one candidate seems to be the Psvane Treasure KT88 (MkII). Does the Penta KT88SC comes close to this (for a LOT less money)?
I realize all this will be partially amp dependent. I have Rogue M180s with KT120 tubes, but it's too solid-state sounding for me. (Never thought I'd say that!) I tried some JJ KT88 but those have the "bloat."
(BTW, my input 12AX7 are Telefunken, and I like their neutrality. I'm not satisfied when I roll them to something "softer" or more "tubey".)
Follow Ups:
1.What speakers you are driving? If with bi-amping option you can try solid state amp on bass and tubes on mid\highs. Will cure the typical tube bass handling.Even inexpensive Hypex DIY will do the trick.Only question of blending sometimes depending on speakers.
2.Sorry but yes Rogue is really most solid state sounding amp even anti-tube one.I would exchange this one if you like tube sound.
Also as I remember JJ had the worst bass handling for my taste, Svetlana however were nice...
Have to disagree Ozzy.
While it is true that the Rogue lacks the common tube amp sound of yesteryears (slow thick sound, rolled off highs, loose bass, etc.) it sounds nothing like the solid state amps I have owned (Bryston, Sim Audio, Quad 606).
My Rogue sounds like the tubes I put into it. If I load it with Mullard EL34s, Mullard 12ax7s and RCA grey glass 6sn7s I can make it sound like a very tubby tube amp. Even with fast linear tubes like KT66 it still sounds like a tube amp.
Different tube amps sound different, just like different solid state amps sound different. If you don't like the Rogue sound, hey its a free country! Buy a EL34 amp with tube rectification if you like that sound. No right or wrong in this hobby, if it sounds good to you enjoy!
Well, taste is very personal and individual thing . I just tried to refresh my hibernating state after some 8 years sleeping by waking up and collecting different amps from friends and friendly dealers with newer tube types to refresh my feeling if I'm still ok or missing something. Actually my point was to check on KT150 coz I really liked CAT monoblocks sound driving some Raidho stuff during recent opportunity. So I brought to my home old Mac 275 with 4 kt88, very old but still alive and kicking Musical reference 8x El34,Ayon Triton 8 KT150, even Cayin with kt 88 and Lyric with kt150 for curiosity sake, also new AR 75 and Rogue with kt120.put it against my old and unfancy Cary 120 8xkt88 svetlana and small sli-80 with original EH kt88.Speakers were Kef Blade2, Wilson Sophia3,Maggie 3.7 and 1.7 as well. Making long story short:old Dennis Hud's stuff blew all of them out completely and Rogue was worst IMHO
Hi Ozzy.
I am familiar with the Cary amps you mention particularly the sli-80 integrated, which is one of the "tubbiest" sounding modern amps around IMO. Agree that it is about as far from the Rogue "house" sound as you can get with another tube amp. If that is the sound you are looking for than no doubt that the Rogue won't be to your taste.
Also agree that the Rogue amps don't sound very good with Tung Sol KT120.
My Rogue has seen quite a bit of modification and this has definitely resulted in a better sounding amp.
The KT150 is supposed to be a great sounding tube, much better than the KT120, too bad the Rogue can't use it.
Cheers!
Hi Mendel,
Yes I agree with you that your mods should bring definite improvement to the sound, however what struck me is not the difference in tubey/lush sonic signature but difference in amount of details and 3d of soundstage between all those amps. Handling of midbass/bass was another issue. Chinese offerings(Cayin/Lyric) were most guilty of fake tubey sound with no resolution at all. Ayon despite offerring most potent combination of KT150x8 was most sterile sounding, while subduing bass notes -- it also shrinked the rest of the bandwith and soundstage proportionally .All amps/tubes combination however failed on tube/ bass handling ..playing overcooked recordings like Stockfish label Cris Jones/ Moonstruck or Sara.K/Water falls or even Mark Knopfler 2002/The ragpickers dream/track#4 A place were we used to live(torture for tube bass) resulted in pure distortion. Wilson Sophia could not be bi-amped but fortunately Kef Blade2 yes. So I tried to run some hypex and bryston amps for bass only duty… It was not bad at all.. I was not satisfied with the blend but think that more carefull implementation via active crossovers and Dsp could finally resolve the issue. I will return from vacation in a couple of weeks and will try that approach or via computer with 8 channels/XO/PQ or via. MiniDSp stuff.
Cheers!
The upper bass "bloat" is there to some degree in my Rogue amp with any KT88 I have tried but disappears with any KT66/6L6 I have used. Maybe "bloat" is the wrong word, it is more a thickness in the sound in the power region of the music that obscures fine details that other tubes can bring out. KT88s do have their good features-- power and punch (aided by the "extra" output in the upper bass we are discussing), and "bloom" that gives them a spacious sound. In many amps and systems that may be just what's needed. KT66 might sound too linear and dry in these systems. No tube is perfect for all amps or systems.
I have already changed the caps in my amp to V-Caps and Mundorf Supreme by the way.
I am on record as not being a big fan of Tele 12ax7 and Tung Sol KT120. A toxic combo In a Rogue amp IMO.
The grey glass PisVanes, Treasure KT88 black glass, Penta Labs solid plate and probably the GL KT 88 should all be better than what you have, but all still have the characteristic KT88 sound in the upper bass/lower midrange. You will have to go to a KT66 if you want to be totally ride of it.
Enjoy the Roll!
Edits: 08/23/16
Thanks very much Mendel -- that's a very helpful and on-target response to my original inquiry.
BTW, I contacted Rogue, and Nick does not recommend using KT66 in the M180s. However, he thinks KT77 might work to get a more linear sound compared to KT88. (E.g. Genalex KT77)
Of course everyone is suggesting that I roll the 12AX7s, and I'm doing that too. I agree that the Telefunken+Tungsol combo may be toxic -- turning a nice tube amp into a SS amp.
Very surprised Rogue does not recommend KT66 but does KT77. The bias range in the amps should easily accommodate KT66--maybe check with Mark?
KT77 will definitely sound different and will not have the KT88 "bloat". I have tried JJ KT77 in my Rogue and like the sound but it is definitely thinner than KT88 (or KT66) in my opinion. Have not tried the Gold Lion reissues but they seem to be held in high esteem.
Good luck and let us know what you try and how it works out.
It may be just Nick's opinion of the sound of KT66 in M180 amps.
I'll check with Mark regarding the use of KT66 in M180 based solely on electronics.
From Mark at Rogue:
"The plate voltage is somewhat high for the KT66, which is why we don't recommend it in the M180. The Gold Lion KT77 reissue sounds terrific and is electrically compatible."
You can talk to Nick or Mark (or Mark & Nick) & get the same answer.
They know their product & the best advice you will get. But, why trust them. Buy some Kt66's & see what you think.
In your system you never know ?
if your amp can handle higher heater current the yugo "Ei" KT90 is first choice for lean bass performance.
N.
"Science only illustrates the current state of errors"
Forgot about that tube. Very good bass performance.
I think TC tubes still has some available. It will cost you though.
Anywhere above the midbass, I still think the Pisvane grey glass KT88 outperform the EI in my Rogue to my ears.
Mendel - do/did you have the Type II of EI KT90?
Yes the type 2 with the weld marks all over the plates.
hmm....i do not agree in that special PSVANE KT88, sorry. i also ran them in my rogue ATLAS MAGNUM but gave them away again. too neutral and analytic, not crispy at all. but may be, your gear can handle them better.
N.
"Science only illustrates the current state of errors"
is bass that is soft and lacks definition. The sound has little impact as the dynamics are poor. Kinda like the bass of those rice burner cars or lowered pickup trucks that kids cruise around on Sundays.
Ok, that may be an a really bad case of bass bloat but something along that lines?
PS i pity those kids, as they don't realize how much they have ruined their hearing by abusing their ears to such an extent.
I don't think i have ever ran across an amp with a bloated bass sound that was cured by simply changing the power tubes. to me that is a sound that is caused by a poor circuit design or an external or room problem.
Also you mentioned that your amp is too solid state sounding with kt120 but with jj kt88 the sound is "bloated". Perhaps, you should check if the bias needs to be adjusted as the power difference between the 2 different types could be an issue. regards, Dak
I would not blame your KT120s. May not help that much by swapping out for KT88s. Would suggest you determine who's (what mfgr's) coupling caps are being used.
To add more of that organic type sound, solder in a set of Jupiter copper foil caps. They are so good, I am using them now on SS gear too.
best
John
+1 on the Jupiter copper foil caps. :-)
We use the Genalex KT-88s in our Citation II amp rebuilds - they are absolutely great. No bass bloat at all. Superb tube!
We use the Genalex KT-88s in our Citation II amp rebuilds - they are absolutely great. No bass bloat at all. Superb tube!
Absolutely.Those are my overall favorite as well.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
Steve Brown and I were the only two that built the Soloist 88 Mullard 5-20 mono blocks from Diyaudio.com that Eli had a hand in. Even after triode wiring the EF86 and losing the NFB, Steve was unimpressed running Sovtek KT-88s and set about converting what he had to 300Bs.
I had trouble completing mine and visited him for help. He quickly got them running and we listened to them, now with my Genelex Gold Lions. Everything the same except the output tubes, he marveled at the difference and before I left town he had begun reversing them back to the original KT-88 Mullard circuit.
That's hard to say, since the bloat you talk about could be coming from your room, your speakers, amp/preamp or some combination of the above. The KT88 can do pretty solid bass with the right equipment and room.
Can your amp run other tubes (whatever the bias method). And if you have a fixed bias amp, you could play with the bias (Fixed bias is the adjustable kind; cathode bias has no adjustment). But just understand, the more fixed fixed bias you add (above the recommended range), the harder you run the tube.
You can also try the 6550/6550A no matter what type of bias you have.
But I will say this, all KT88 tubes have the same basic sonic characteristics - heavy hitting. If it's feasible, according to the manufacturer, try a KT66. Way different sonic signature, but not as "bassy" as the KT88/6550, much smoother in the Treble and mids.
:-)!
Warmest
Tim Bailey
Skeptical Measurer & Audio Scrounger
Where do we stand these days in terms of a linear sounding, current production KT88 without excessive upper-bass/lower-mid bloat?
Those tubes you mention are very good..There is also the Shuggie Treasures are great tubes as well. The Genelex Reissue Gold Lions are always a crowd favorite and you can alter the sound with your driver tubes.
I realize all this will be partially amp dependent. I have Rogue M180s with KT120 tubes, but it's too solid-state sounding for me. (Never thought I'd say that!) I tried some JJ KT88 but those have the "bloat."
I would work with the smaller tubes in the amp because that will help with a more influential change..If you can't get it with tubes,you may need to upgrade the coupling caps in your amps.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
I agree with Mike. It will be a lot cheaper to play with input tubes and capacitors than octets of tubes.
I have not tried the Treasure KT88's but the KT66z tubes are 'richer' than the GL KT66.
Frihed has made some excellent observations regarding 6550s which are very dynamic, hard hitting tubes which leave no time for bloat. To me they are not musical so I don't use them. I use the current standard - the Russian Gold Lion KT-88s. I remember the JJ's differently than Mike and thought they `were very clean sounding, but I could be wrong it has been a while.
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: