Midrange Increasingly Harsh


Lately I've noticed some harshness in the mid-range, especially with violins, clarinets and female voice.  I recently bought a CD of female plainchant, and she hits the un-sweet spot so frequently I can't listen to it.  I don't listen at high volumes, rarely over nine o'clock on the volume knob.  The sound is not anything unnatural, just a less musical presentation and an unpleasant harshness.

 

I have twenty year old Forest Totems with their original cones, a Prima Luna Dialogue One amp which got new tubes about five years ago and an Arcam CD-73 which got a factory rebuild about three years ago.  I have neither the money nor inclination to just start arbitrarily replacing parts, but would appreciate some insight and guidance on likely culprits. 

Thanks,

John Cotner

New Ulm, MN

jrcotner

Do the tweeters have ferro fluid?  That can need to be replaced after many years, as it turns into sludge.

You may also have some capacitors in the crossover that are drifting from original values.  

Tubes are a consumable, and should be checked now and then.  How's the bias on the output tubes?

Potential sign of tubes needing replacement?

Also not fun to think about, but as we (and our ears) age, harshness can start to become increasingly worse, especially with speakers that tip towards being more on the detailed side.

Source; Pre/Amp; Speakers: Isolate the Problem.

Other speakers you can put in the system?

IF you have, or a friend has a fairly portable pre/amp setup, even an old receiver or AVR, you could try using that, it will isolate the problem: speakers or amp.

btw, this happens on more sources than your CD player, correct? If only CD, try a different one temporarily. Buy some cheap thingy from Amazon that is returnable.

Live near me, New Jersey 07062, I've got lots of stuff to help isolate this and/or that.

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Maybe the cheapest/easiest option would be to do some tube rolling in the PL amp.  That’s where I’d start, and best of luck. 

Has this happened on both speakers or just one?

Have  you moved things around in your listening area which could affect acoustics, or moved the speakers further into the room?

Try switching the output taps on the speaker connections -

If you are using the 8-ohm taps try the 4-ohm and 2-ohm.  

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Probably need new tubes as noted above. 

If that doesn't do the trick, I believe your tweeter is a Seas 25TAF/G which appears to use ferrofluid.  Depending on the ease of tweeter partial disassembly, you may be able to change the fluid yourself.  Some are simple to do, others not simple at all and your risk damaging the tweeter.

If it was my tweeters, I would not hesitate to send to Millersound who only does speaker repair.  He is excellent and if past performance is indicative he will turn them around in a day or two.  Price will be very very minimal. 

The ferrofluid being bad is definitely a secondary possibility to needing new tubes.

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Thanks for the info.  I get the harshness with CDs as well as records.  I've changed around the speaker output taps and no change.

I apologize if I offended anyone with my modest problems.  I settled on the Audiogon forum since it looked like it had the most knowledgeable and experienced members around.  If it is strictly for much higher-end participants than myself, please let me know and I will move off.    

@jrcotner 

Your question and equipment fit into this website perfectly and you are equally perfectly welcome.  Don't think twice about it.  In fact, your question is more relevant than many discussions here. 

Call Upscale and ask them if the PL behaves like this when power tubes need replacing.

You can buy 2 matched pairs on Amazon for $89 a pair. 5 years is worth a replacement set.

"I apologize if I offended anyone with my modest problems.  I settled on the Audiogon forum since it looked like it had the most knowledgeable and experienced members around.  If it is strictly for much higher-end participants than myself, please let me know and I will move off."

 

Not at all. This site would be better if people like steakster moved off.    

I concur that tubes are the place to start looking, 5 years is a fairly long time for power tubes if you're listening with any frequency.

The cause of your issue can be anything in the chain from start to finish, including the source material, cables, seating location and the room itself. All you can do is replace one item at a time and listen to see if the problem has gone away. Do you have friends or a friendly dealer, that can loan you gear to eliminate each piece in your system?

I would start with the speakers, but I wouldn’t be shocked if it turned out to be the room.

I had the same problem with the same source material and it took replacing my speakers to fix it. Even with trim pots on my speakers, I couldn't correctly tone down the shrillness and etch without adversely effecting the adjoining frequency ranges. Good luck with what you try.

All the best,
Nonoise

There’s your answer , I recently finished upgrading a pair of older Klipsch

 

the capacitors get dryed out  and start loosing their harmonics it just gets worse 

I replace the resistor so with much better quality then the old cement typeresistors which are gritty , and the stock capacitors in most speakers under $15k is nothing special.  I learned upgrades when I owned a Audio store 

go to Humble homemade hifi capacitor test, you should pul a bass driver out and take a picture, if you are lucky the wires from the Xover are just slide on terminals 

where you can remove the Xover ,if not it’s soldered-in place . If you like them and plan on keeping them that’s what I would do first ,upgraded Xovers sound much better then stock parts ,it’s Like going from a stock engine to a Hot rod. 

Thanks for all of the information, as well as confirmation that I'm in the right place.  I got this tube set from Upscale Audio, so I'll check with them regarding tube behavior.  Room acoustics is an interesting idea, but I've been here for four years and this is a recent phenomenon.  I plan on replacing speakers next year, and would like to get a new amp as well, but my CD player is at the end of its life and needs to get replaced first.  I'll report back when any repairs or replacements are performed. 

With tubes it all depends on how many hours you have on them ,if used often it may be well overdo for tubes to be replaced , and if you have these new modern tube even more so ,I buy only NOS tubes night and day better quality on many levels ,and the small input tubes you can even voice your tone .

speakers that old the capacitors on Anything are drying out gor sure 

I have been modding o for over 20 years and capacitor technologies has greatly advanced. I still see people using electrolytic capacitors in speakers ,why for its cheap and sound like crap very gritty , I just rebuilt a so called crites upgrade 

A electrolytic on the bass $4  i I use poly caps ,or Foil  capacitor depending on budget ,if you have to go cheap and use a electrolytic cap at least put in a 2uf poly or mylar cap on a 100 uf bass cap to filter the highs ,electrolytics belong in power supplies,even they filter with a poly cap if done right , most mfg under $10 k use cheap Xover parts Solen good enough and cheaper ceramic resistors . I refuse to go to their standards ,it’s a petpeave with me , you get what you pay for .

@jrcotner 

 

Good luck, JR.  Some good advice here ... definitely let us know what you find!!

@jrcotner 

As others have said, tubes are consumable.  So there’s that and also different tubes have different sounds.  After five years,  I’d replace at least the output tubes and if you liked the tubes five years ago, then buy more of the same.  But if you didn’t, try another company.  And don’t go cheap!  You get what you pay for.

Another thought.  What time of day do you listen?  I have had the exact same problem later in the evening, but not in the morning. Electric guitars, saxophone’s and women’s voices would hurt!

All the best.

 

jrcotner OP

First: Switch equipment: Isolate the Problem: preamp?/amp?/speakers?

Don't jump around changing tubes before you know if it is the speakers themselves or your amp or your preamp.

go from there

You might have tinnitus!

What is tinnitus?

Tinnitus (pronounced tih-NITE-us or TIN-uh-tus) is the perception of sound that does not have an external source, so other people cannot hear it.

Tinnitus is commonly described as a ringing sound, but some people hear other types of sounds, such as roaring or buzzing. Tinnitus is common, with surveys estimating that 10 to 25% of adults have it. Children can also have tinnitus. For children and adults, tinnitus may improve or even go away over time, but in some cases, it worsens with time. When tinnitus lasts for three months or longer, it is considered chronic.

The causes of tinnitus are unclear, but most people who have it have some degree of hearing loss. Tinnitus is only rarely associated with a serious medical problem and is usually not severe enough to interfere with daily life. However, some people find that it affects their mood and their ability to sleep or concentrate. In severe cases, tinnitus can lead to anxiety or depression.

Currently, there is no cure for tinnitus, but there are ways to reduce symptoms. Common approaches include the use of sound therapy devices (including hearing aids), behavioral therapies, and medications.

What are the symptoms of tinnitus?

The symptoms of tinnitus can vary significantly from person to person. You may hear phantom sounds in one ear, in both ears, and in your head. The phantom sound may ring, buzz, roar, whistle, hum, click, hiss, or squeal. The sound may be soft or loud and may be low or high pitched. It may come and go or be present all the time. Sometimes, moving your head, neck, or eyes, or touching certain parts of your body may produce tinnitus symptoms or temporarily change the quality of the perceived sound. This is called somatosensory (pronounced so-ma-toe-SENSE-uh-ree) tinnitus.

Most cases of tinnitus are subjective, meaning that only you can hear the sounds. In rare cases, the sound pulsates rhythmically, often in time to your heartbeat. In these cases, a doctor may be able to hear the sounds with a stethoscope and, if so, it is considered to be objective tinnitus. Often, objective tinnitus has an identifiable cause and is treatable.

The first step is diagnostic—isolate the source of the problem before proceeding with random “solutions.”  I would start with figuring out if it is from both or one channel.  Preferably, use a mono recording where you hear a problem and, if you have a balance control, swing the balance from one side to the other and listen for a difference.  If you don’t have a balance control, try sitting much closer, and in the direct path of one speaker, then the other, to listen for differences.  The best approach would be to do switching at one end of the system until you find the culprit.  I suggest starting at the CD player.  When switching interconnects, it is best to have the system turned off or the volume all the way down.  Pull one channel and listen to just one channel.  Then do the same to listen to the other channel.  If the problem is in one channel, now switch the single channel left to right to see if the problem moves to a different channel; if it does, it is the CD player or its interconnect that is the source of the problem.  If it doesn’t it is something downstream.  If the problem is in both channels, it will be hard to definitely isolate the problem without trying other gear to see if the problem goes away.  If you have determined it is not the CD player, do the switching routine to determine if the problem is the amp or the speakers.  For this step, avoid playing with one speaker disconnected from the amp (tube amps don’t like this).  Hopefully you will hear any difference with both speakers playing,  If switching left and right speakers does cause the problem to switch channels, it is the speakers at fault.  

As Elliot recommended try an isolate the problem. Most likely its either the speakers or the tubes since you’ve replicated the problem with multiple sources. You’ll need either an alternative amplifier or alternative set of speakers and see if you can replicate the problem after replacing one of them. Also is this coming from both speakers or just one side?

When it comes to tubes its more about hours played then age, power tubes can last around 2500 hrs and preamp tubes about double that, but like any piece of electronic gear, they can fail at any time, if you have single tube or single driver fail the problem would more likely be in one side. If it’s gradual decay over time its would be on both sides. So first see if its the amp or the speakers, then go from there.

I listen at lunch and again in the evening with my adult beverage.  I have post-concussion phonophobia, which I suspected at first.  But my wife also noticed it so I can rule that out.  I don't have any sources for spare gear around here to swap in and out.  What I may try is plugging the CD player into other output taps from the amp, and fooling around with some different cables.  By my estimate I have over 5000 hours on these tubes, so they need to get replaced in any event.  I don't recall the brand but the were made in England and sounded wonderful for a long time.  Hopefully Upscale has my purchase history if I can't run down the receipt.

Yep, I’d do a full re-tube. Your power tubes are definitely shot and the pre-amp tubes are at the end of their life. Try to avoid using it until you get the power tubes replaced at minimum as the distortion from spent tubes can damage the speakers. Fortunately you don’t play at high volumes so hopefully the drivers are unscathed.

Congrats on averaging 1k hours a year of listening! That’s tremendous. I work from home and even then I doubt I’m half that.  I think I'll do some listening now and try and catch up lol. 

Even if it is not the tubes getting worn, it is helpful to have a full complement of replacement tubes.  Any time you suspect tubes are going bad, you can then do substitutions to see if that cures the deterioration.  Even when you don’t hear an obvious problem, performance can decline gradually and you may not notice this until you do substitutions.

OP mentioned the problem persists from BOTH CD and TT, sooo, that rules out source equipment.

It is unlikely both speakers would develop problem(s) at the same time. So, simply switching speaker wires, left to right, right to left, NO OTHER CHANGES: IF the problem moves to the other side, it's that speaker.

Tubes: get paper, make notes, easy to confuse yourself or forget. Swap all tubes L to R, problem move? Next: using tubes from the 'good side', swap l/r one at a time, any single tube swap make a difference?

Many tubes last 10,000 hours, so 5,000 hours is not a DEFINITE answer. Ask seller about the tubes you bought from him, what are the life expectancies of the tube types your unit uses?

...................................................

How many times have I advised a simple tube tester to give answers when problems occur????????????????????????? Blindly buying tubes is an expensive shot in the dark.

 

I did some side-by-side testing yesterday and discovered that there is no difference between the left and right speaker.  I swapped cables and no change.  But when I changed from the eight ohm to four ohm output, the harshness decreased somewhat.  My bride couldn't tell the difference.  I got in touch with Upscale Audio and ordered a set of Tung-Sol EL34B power tubes.  We'll see how that goes then get some new 12AX7 and 12AU7 tubes.

 

Handy to have a decent small SS amp around.  :)

If Speakers,

If I remember the Totems used the XT-25 tweeter that is anything but harsh. So I will have to be on the tube guessing camp. Note the range you may be hearing may actually be woofer breakup. Also note, if I got my speakers correct, the Vifa is great above 4K, so that puts quite a strain on the woofer. Anyone who tries to use the Vifa much lower, well it's distortion skyrockets as it just does not have the surface area. 

Now, harshness is an issue. Due to the loudness wars, a lot of newer CDs are quite hot. Doe to how digital filtering works, there is rick of digital clipping in the DAC. This is why I set my JRiver to the default -1 dB and some suggest -3.  It helps on those female vocals, Judy Collins, Joni Mitchel etc.  I have also found differences in DACs to make this more or less sensitive. Some DACs, like the RME have this internally. I do not know if any CD player does. 

I replaced the Mullard  EL-34 tubes with Tung-Sol EL-34B tubes and after some run-in time I replay the Hildegard Von Bingren CD which started this.  The sound is much improved and not nearly as harsh.  The higher register soars rather than screeches.  I don't have back-up 12AX7 or 12AU7 tubes so need to get a set of them as well.  I'll roll them in to see how things change.

Is impossible to get good sound from low grade speakers, you can do anything but it does not help. 

FWIW, I've noticed some distortion in my PL amp. I changed out  the power tubes - different tone but distortion still there. Short version, I finally just put in new drivers because I had back up ones of the same type/brand, etc, because I like their sound. Bingo! Everything's fine now a the cost of just two 12AX7's. 

@jrcotner 

This is an extremely common problem call sibilance. The problem is that our ears are most sensitive at frequencies in the 3 kHz to 4 kHz region exactly the same frequencies reflections in most rooms are loudest. It is more common with dynamic speakers with broader radiation characteristics. Horns and planar dipoles are not so affected because they are directive.  The solutions are use an EQ curve with a Gundry dip in it. Or get down with some room treatment. You need to put absorption at all first reflection points walls ceilings and floors. Or you could get yourself a set of horn or planar speakers but you might still require some room treatment although it should be a lot less. I Use 8 foot tall ESLs 36" wide. The only room treatment I needed was three rows of 4" foam acoustic tile directly behind the speakers. Still the occasional recording will cause some sibilance due to the way they were mixed. 

It remains unclear as to what might be going on here.  First, the OP reported a developing problem—one that was not present at first, but came to be and has gotten worse.  If this is true, and is not a hearing problem, then it is something in the equipment that is going bad.  If it is equipment going bad, the prime suspects would be the tubes or the ferrofluid in the tweeters drying out.

But, it could also the case that the OP did not notice this issue at first, but now that he is aware of it, it seems to be getting worse because he is focused on it.  In that case, suggested cures by room treatment or equalization may make sense.  Again, I would suggest experimenting with nearfield listening to reduce the influence of the room on the sound to see if the room is the primary source of the problem.  If nearfield listening cures the problem, but is not otherwise practical, one would still be informed as to room problems that can be attacked with treatment or DSP compensation or equalization, change in speaker or listening chair position, etc.

The improvement when using the 4 ohm tap is an interesting clue.  That tap has a reduced source impedance (the output impedance of the amp) and this reduces the frequency response changes attributable to the interaction with the speaker’s changing impedance at different frequencies.  This, as mijostyn suggests, might be a problem associated with a boost at certain frequencies.  The “cure” might be equalization or even using a solid state amp because such amps inherently have low output impedance.

That you changed speaker wires to the 4 ohm taps on your amp b4 replacing the tubes and heard a slight improvement does show component issue between speakers and amp and replacing the tubes should return the sound to what you're used to. ferrofluid drying up in tweeters is also very real and likely to affect sound before xover components wearing out. Listen to me acting like I know what I'm talking about, lol. You've been given a good lead to get your tweeters serviced and it might be worth it to you to be without your stereo the week or two just to have them tip top. Either way, good luck.