[Chief Bonehead Class Spring 2024 - New Iterations of the La Scala and Klipschorn Coming]

So, if I'm understanding right, if one wanted to go the DSP route, it will absolutely be required to have three separate stereo power amps, one for each frequency range? (e.g. one amp driving left hf and right hf, one amp driving left mids and right mids, and one amp driving left lf and right lf)? Can't get away with, say, two amps?

 

Even if you don't factor in the cost of tri-amping, it sounds like the inclusion of the DSP electronics will mean that these new versions will likely cost significantly more than the AL5 and AK6, which are already very expensive. Exciting but kind of terrifying in that sense.

 

Also, will AL5/AK6 owners be able to upgrade the active DSP xover, or only be able to upgrade the horns and drivers?

[Will Kilpschorn AK6 work well in my room? (thinking of upgrading from La Scala)]

2 hours ago, Shakeydeal said:

Good on ya for moving the tv out of the room. You’ll definitely notice an improvement on that for sure.

 

Yeah it's the change I'm most excited for tbh lol.

[Will Kilpschorn AK6 work well in my room? (thinking of upgrading from La Scala)]

One thing I'm curious about: although the La Scala AL5s are rated down to 53 Hz, I have found from REW measurement using a calibrated microphone that below ~90 Hz, the bass response drops like a stone. No change in placement (moving them around in the corners that they are in) seems to be able to change this. Hence the absolute necessity of having the REL 212s, which are crossed over at about 90 Hz which is very high.

 

The KHorns are rated down to 33 Hz. Given my LS only made it down to 90 Hz instead of 53 Hz, I'm wondering what to realistically expect from the KHorns in room? I'm really hoping that they can get down to at least 40 Hz before losing SPL so that subs don't have to be covering such a large frequency range. I know that nobody can say for sure how they'll perform in my room, but if anyone has anecdotes about measured bass response of LS vs KH in their rooms I would be interested to hear it!

[Will Kilpschorn AK6 work well in my room? (thinking of upgrading from La Scala)]

3 hours ago, Peter P. said:

Sometimes you have to ignore the acoustic ramifications and meet your other needs.

 

You're right; LaScalas and two huge subs take up way to much space along that short wall, and in the room in general. Placing a pair of Klipschorns in the corners

is the right solution.

 

Few people have the ideal setup for a pair of Klipschorns yet they enjoy them just the same.

 

I say go for it with one caveat; since you've got the TV screen I assume you watch movies. You'll want to use one sub for movie effects as you have mentioned so you'll

have to find space for it. Sounds like you have a plan for that.

 

I would say that the acoustic ramifications are about equal to the other needs here. I don't want to be taking a downgrade from how things sound now, but yeah I really would like to clean up the arrangement of the room and footprint of what I currently have. As for the TV, I'm actually moving it to another room. I rarely use it and I have a nice atmos soundbar system with its own sub that I can use on the rare occasion that I do. Doesn't sound as good as my hifi system but that's fine. I don't want this room to be TV centric and would rather it just be a nice hang out space where seating doesn't need to be oriented towards a screen. Anyway, for subwoofer, my plan would be to either keep one of my 212s, or drop in my REL HT1510, either of which should be able cover the KHorns well up to 40 Hz where I suspect they'll start losing steam.

 

4 hours ago, Flevoman said:

I don't know if my experience is the right one to use, but I still want to share it.

 

I own the AL5 myself and, like you, was hesitant about acquiring someone else's AK6. I went to listen to his speakers twice, and both times I had the same experience. I found the AK6 to have a much tamer, maybe even somewhat dull, sound. The AL5, as it sounds in my home, has much more dynamics and punch. Also, I found the placement at my home better than at his. I'm not sure if this is due to the speakers, the setup, or the acoustics, but this is what I noticed. The bass went a little deeper, but I didn't find the difference, with the tracks I listened to, noticeably large. If I had to describe it briefly, I would say the AL5 (as I know it) is dynamic and lively, while the AK6 (as it sounded there) is more laid-back and grander.

 

Note: he had his Khorns placed against the long wall, not in the corners. And this person likes a laid-back sound. It is likely that he has tailored his setup to this preference. I personally prefer a dynamic and lively sound. By the way, this person is in a position to listen to different Khorns daily, which are placed well in the corners, and according to him, the audible difference between the set tightly placed in the corners and his set is minimal.

 

Thanks for sharing your experience! It does give me pause. I read your thread from when you were trying to decide, and I (perhaps naively) feel like you did in that I would expect the Khorn and La Scala to sound the same except for the bass, given that the tweeter horn and mid horn + drivers appear to be identical? Although that seems not to be the case.

 

3 hours ago, Frzninvt said:

Too narrow not wide enough for them to image correctly.  You should have at least 4ft of wall on either side once they are in a corner.  You are better off with the La Scala's.

 

 

Thanks for the input! If I could dig in a little more into what you mean: when you say 4ft of wall on either side, you mean flat wall extending out from either side of each Khorn from where the khorn ends? I agree that the windows hurt this on 3 out of 4 sides. But for what it's worth, the windows only impeded ~half of the height of the bass bin. I wonder if that'll help.

 

Re: not being wide enough to image properly, are you talking purely about tweeter/mid horn angle due to corner placement (which could be, to some degree, aided by toe out) or are you implying that the windowframes compromising the bass horn extension will hurt imaging?

 

Thanks again for your thoughts!!

 

 

General question: this isn't a dealbreaker if not, but I'm wondering if there are any comprehensive professional reviews of the new AK6 model from any publication that are positive? The vast amount of what I've found written about KHorns on the internet (and on this forum) are not about the AK6 (which is understandable given their super high cost), but I would like to read as many impressions as I can as I mull things over.

[Will Kilpschorn AK6 work well in my room? (thinking of upgrading from La Scala)]

18 minutes ago, Khornukopia said:

 

This is a perfect opportunity to answer all the nagging questions about your amp. (or the electricity source it is plugged into)

 

Sure is, but I can't disingenuously show up to someone's home to try their speakers unless I want to buy them. Hence I hope to get answers to the questions I'm asking about how well the bass extension will work in my corners, and how well they'll compare to my AL5s in my room  

[Will Kilpschorn AK6 work well in my room? (thinking of upgrading from La Scala)]

19 minutes ago, Khornukopia said:

 

I also was thinking about the earlier K-horns, like mine. Yes, the AK-6 with the enclosed backs can be turned towards your desired position. But then they start to have a bigger footprint than the La Scala.

 

Pulled out to where they sound best, my La Scala have an effective foot print of 3.5' x 3.25' measured from the corner. Even in an extreme case where I have the Klipschorns facing with the tweeter horizontally along the room, their footprint would be 2.3' x 2.6' ish feet. So I think no matter what I'm winning with the KHorns. But also, part of why I want to do this is to eliminate the need for my pair of REL 212/SX subs to add bass to the La Scalas. The 212s need to be out in the room to sound good and have a huge foot print themselves. I'm hoping that the bass extension of KHorn in my room would allow me to replace them with one smaller single-driver sub (like a REL HT 1510).

 

So maybe a better way of rephrasing this question is: will AK6s placed in these corners be able to use the corner loading effectively enough to give me good bass response? Higher freq stuff is important too obviously, but again I assume I can fix that with toe.

 

In reading people's analysis of Stereophile's poor review of the AK6, I saw a lot of people saying that he just doesn't have a good room for KHorns. He also had his on a 12' wall if I recall, although the length of his room was much shorter than mine (17'?).

 

13 minutes ago, Khornukopia said:

@ThomBoh , Take your Decware amp to audition the local AK-6. 

 

That's definitely the plan if I decide I'm serious about them

[Will Kilpschorn AK6 work well in my room? (thinking of upgrading from La Scala)]

3 minutes ago, Shakeydeal said:

Kind of a narrow room for khorns. You will be sitting way off axis with the speakers crossing well in front of the listening position.

 

 

 

Just my opinon.

 

 

I appreciate that. Can I not just fix that with toe-out? They're AK6 so they don't have to be snugly sealed to the corner because the backs are sealed. At least Klipsch makes it sound like you can.

[Will Kilpschorn AK6 work well in my room? (thinking of upgrading from La Scala)]

3 minutes ago, Khornukopia said:

I would put Klipschorns on the long wall of your 12'x30' room, even if you need to add a free-standing corner at one end. That places your listening position on axis with the tweeters. The dimensions may seem counter-intuitive at first, but it often works good. Try it with your La Scalas before buying the K-horns.

 

Unfortunately, speakers on the long wall is just not an option for this room, especially not with speakers this large. The length of the room is awkwardly broken up by doorways, inset bookcase, etc and the only way to have a liveable furniture setup that makes sense in this room while being able to also use it as a listening room is to have the speakers in the corners on the short wall.

 

So, do you see issues with putting the KHorns in the corners shown?

 

I'm not sure I understand what you're saying about tweeter axis. In the corners shown I can toe in/out to get whatever relationship between tweeter axis and preferred listening position I would want? Can you be more specific about what you mean?

 

Thanks for the advice!!

[Will Kilpschorn AK6 work well in my room? (thinking of upgrading from La Scala)]

Similarly, would putting a couch on the left sidewall next to where the left KHorn would be hurt anything? I guess a better question is: what on your sidewalls DOES hurt the bass performance of a Khorn?

[Will Kilpschorn AK6 work well in my room? (thinking of upgrading from La Scala)]

There's a local pair of Klipschorn AK6 for sale, and I'm considering them.

 

I currently have La Scala AL5s, and while I love them, I think the AK6 could do my room a lot of logistical favors. My AL5s together with my pair of REL 212/SX subs take up a pretty large footprint in my room. The LS sound better pulled out of the corners, and the subs end up with a dip from 60-90 Hz unless I pull them out into the room and have them against the sidewalls. They're big and really act as obstacles to layout of my room.

 

My thought in getting KHorns is that the speakers themselves would effectively have a way smaller footprint than the La Scalas as they would be tucked right into the corners, and the fact that they have much deeper bass extension than the LS would mean that I could probably get away with one smaller sub (like a REL 1510) sitting between the KHorns on the front wall, eliminating the annoying footprint of my REL 212s. I also would hope that since all of the bass from 40 Hz up will be coming from the KHorns, I'll have a much smoother and more even bass response in my room overall. My hope is that this would not only make my room much nicer, but also sound better (or at least as good). Also, I might save money in the long run by going with the KHorns because I could sell the REL 212s, which themselves are very pricey.

 

My biggest concern is that in reading threads from people considering KHorns vs La Scalas, it has seemed like people for the most part prefer the La Scalas, and the KHorns could only be as good if I have the right corners for a KHorn to really work properly. Also, the very few professional reviews of the AK6 that I've been able to find don't actually read very favorably. I would hope that this is due to limitations of the reviewer's rooms. Any candid opinions of the AK6s as a speaker, and compared to the AL5s would be appreciated!

 

So I'd like to ask.. do I have the right kinds of corners? My room is 12' x 30', here's a photo of the corners where the KHorns would go (forgive the mess of speakers, I'm doing some testing right now). You can see where one of my REL 212s is on the right -- there's another one on the left side a little further back. It's super annoying even though it sounds great.

 

That front wall is 12' wide, and the distance from corner to window frame on either side is 4'. The distance from corner to window frame along the right side wall is 3.5'. Would these window frames have a significant impact on the ability for the folded bass horns to work as well as they should in these corners?

 

Thanks for any thoughts people might have on going from LSAL5 to KHAK6 in this space! I'm hoping I can pull it off and reclaim more of my room layout without giving up sound quality in the process!

[Need Help: Decware + La Scala or KHorns]

51 minutes ago, mark1101 said:

I bought a pair of SE84UFO.  I bought these on 4-10-22.  At that time I was around number 1200 on the real time build sheet.  Today I am at around number 380.  Doing the math Decware builds around 400 to 450 amps per year (all types included).  It will be close to another year for me.  So around a 3 year wait.

 

Right now I see over 2400 on the list.  That would be over a 5 year wait (closer to 6) the way things are presently going.  Enjoy fellas.

 

I feel like if I eventually don't want these amps I could double my money in about an hour.

 

By the way I can use them on any of the Heritage in my signature.  I had planned on the lascalas.

 

I require near silent equipment.  Anything else and it won't be in my house.

 

Well, the sorta-good news here is that the SE84UFO is a different design than the UFO25, and might have a different noise spec. As evidence in this direction, Andrew Robinson specifically mentioned in his La Scala review that the UFO2 was a fantastic match for the La Scalas, so that tells me that the UFO2 must have a lot less hum than the UFO25, and I'd expect the UFO to be similar to the UFO2 rather than the UFO25. But this is all "informed speculation" on my part.

 

If I come across a UFO or UFO2 on the used market I might grab it just to compare against the UFO25 and try and satisfy my curiosity on this.

 

Better news is that if you bought a pair of the UFOs with the intention of using them as differential balanced monoblocks, then you're in the clear. My UFO25s in balanced mono are humless and sound great on my La Scalas.

[Need Help: Decware + La Scala or KHorns]

3 minutes ago, mark1101 said:

Can we hear -68db?  Seriously, I am waiting on two of these amps.

 

That spec doesn't tell you what you will hear from your speakers in your room at listening position. For me and my speakers, this translated to a 58ish dB hum at listening position, which is very, very noticeable (for reference, with the amp off, ambient noise in the room is about 43 dB). Happy to send you a video if you would like.

 

Which amps did you order? I'm talking specifically about the SEWE300B, but the UFO25 gave 55-56 dB of hum which is also not bearable imo. Which speakers were you planning to pair them with?

[Need Help: Decware + La Scala or KHorns]

25 minutes ago, Khornukopia said:

In all fairness to the reputation of the amp builder, I think it would be considerate to prove that your house wiring, and/or your electric power source is not contributing to the hum. I have witnessed some strange things with electrical circuits over the years and am really curious about the cause of your hum. In the 2 weeks since posting to the public on this forum, have you carried your amp to a friend's house during this time to compare? Sometimes the process of elimination is the only way to realize what is or is not causing a problem.

 

 

 

 

I agree. I've had two electricians over, and consulted with a third, all of them have said that everything looks great. The wiring is much newer than the rest of the house and is modern. Ground examined and tested, as were all outlets. I also got my own outlet tester for my own gratification. I don't have any friends with passive speakers, unfortunately. I do plan to bring it to a hifi store that has La Scalas or KHorns set up at some point, but have not been able to yet. It seems unlikely at this point, though, that there is any issue with my house's wiring, and Steve has agreed that this is the case. Nonetheless, I will test the amp elsewhere whenever I get the chance, as I think I'll need this to satisfy my own curiosity. But bear in mind this test needs to be on highly efficient speakers to be meaningful here -- having a small amount of hum from normal-high efficiency speakers is within spec according to Decware.

[Need Help: Decware + La Scala or KHorns]

1 hour ago, jjptkd said:

 

 So is the hum coming through the speakers or from the amp itself? Forgive me if this has been asked already. 60db hum is obviously unacceptable. 

 

From the speakers. There is a very faint buzz from the amp's transformer itself, but that is very quiet and absolutely negligible here.

[Need Help: Decware + La Scala or KHorns]

15 hours ago, Silverfoxvtx1800 said:

I can personally tell you that the solid state Class A,Pass Labs XA25 and the Pass Preamp or the int-25 integrated Pass don’t hum and are dead silent in the Klipsch speakers…last time I looked there was a couple Pass Labs int-25 amps on USA audiomart…at a decent price….and no tube worries…

 

I don't doubt it! Pass makes great stuff, and of course solid state is immune to the type of hum we're discussing here. I might try them out one day, but right now I'm enjoying tubes (my UFO25s sound fantastic and humless configured as differential monoblocks).

 

14 hours ago, 83 LSIs said:

Anyone that worries about tubes probably shouldn't have a tube amplifier, hum or no hum. 😉

 

I find it odd that the UFO25 and 300B amplifiers need to hum to sound good?

Having owned or heard several not 25 versions of the SE84, an original Taboo, the SE34i, and even owned the original blue Torii (a different sort of p/p) without hum issues, not to mention other brands of single ended tube amplifiers that were quiet. 

Even my diy ~7 watt SET amplifier is silent.

 

My understanding from my discussion with Steve is that the hum is certainly not required to sound good, but is required for the amp to sound exactly the way he wants on the types of speakers he is targeting. He said it would still sound good without the internal hum, just not special in the way that he wants. Yeah my SE34I.5 is nice and quiet on my La Scalas, very very little hum, and fine for everyday use. Doesn't sound as good as the UFO25 (in mono) though! Based on the testimonies I've gathered and reviews read, the non-25th anniversary UFOs seem to just have less internal hum than the 25th anniversary version. Not sure why. Steve has told me that different models of his amps indeed do have different levels on internal hum (e.g. 300B > UFO25 > SE34I in hum level).

[Need Help: Decware + La Scala or KHorns]

11 minutes ago, babadono said:

So @ThomBoh barring anything magical going on I think you have checked everything. The fact that manufacturer specs 120 HZ only down 68dBu and the 60 HZ only a little more this is why you are objecting to it. Now only you can decide if you can live with it. I could not..but hey that's just me..I relocated all my power amps to a remote utility room because I could  not stand the transformer hum.

Thanks for your thoughts. Oh I know for sure that I can not live with it. Personally, I do not think that anybody could. It is not subtle, it is loud. Notes fade into the hum, not silence, and that has a huge effect on how the music sounds and amount of detail and texture heard. It also rules out low volume background listening. If I had the amp on with no music playing, and other people were in the room talking/socializing etc, I would expect that they would all be pretty annoyed by it.

[Need Help: Decware + La Scala or KHorns]

27 minutes ago, Shakeydeal said:

That’s a shame because there are very few speakers that will be optimal with such amps. Notice I didn’t say “work with”.  Because there are many that will sound good, but those aren’t an ideal pairing and won’t give you the best performance of amp or speaker. So what Steve thinks is acceptable levels of hum limits the use of his amps with speakers that would make them sound the best.

 

Yeah, I think it's interesting that the conventional thought is that the lower powered an amp is, the higher efficiency the ideal matching speaker would be, but in the case of the SE84UFO25 (2.3 watts) and the SEWE300B (7 watts), that does not seem to be the case -- there is a limit on how efficient the speaker can be before hum becomes an issue. Nonetheless, I believe that Steve has given a lot of thought about how he wants his amps to sound, and what kind of speakers are ideal pairings with them (and he has written a huge amount about this on the decware forums).

[Need Help: Decware + La Scala or KHorns]

Hi everyone! Sorry to take so long to update, some urgent work stuff came up and I spent some time out camping.

 

Unfortunately, the issue persists!

 

On 2/21/2024 at 11:46 AM, Shakeydeal said:

 

That's a good suggestion. Also, you could take it to a friend's system. Even if they don't have high sens. speakers, if the amp has a hum, it'll still be present, just much lower in volume.

 

I actually have a pair of Zu Dirty Weekend 6s (~95dB) that I hauled over to my living room and hooked up to the 300B. There is a very low amount of hum, totally bearable. Makes it seem plausible that we're dealing with an intrinsic hum that is just going to be louder for higher efficiency speakers. That said I would really like to bring the amp somewhere that has La Scalas or Klipschorns set up just to see if we get the same hum -- hoping to do so in the next week or two if I can find a local hifi shop willing to oblige. I think this would give conclusive evidence of whether or not it's just the amp's inherent hum.

 

On 2/21/2024 at 12:07 PM, babadono said:

@ThomBoh sorry if I missed it...are you shorting the inputs when trying this hum test with just the amp and speakers? There is a SCIENTIFIC way to troubleshoot these types of problems. If with only the speakers connected to the amp and the inputs to the amp shorted and there is hum there is something wrong(or inherent) in the amp. Given another amp running off the same power outlet is fine.

 

Yes, I tried shorting the inputs, and the level hum I'm getting is actually independent of whether or not the inputs are shorted. Thanks for the suggestion, and would be happy to hear if there are any other things I'm missing here

 

On 2/22/2024 at 8:17 AM, sanblomo said:

Hi, I'm not a Klipsch owner, but I have open baffle speakers which are 100db efficient. Also, I have a pair of high sensitivity Audio Note AN-E. I waited for over two years to get my Decware amp. I switched my order to the 300B amp about eight months ago from the SE84UFO25. End of January I finally received the amp and plugged it in. To my disappointment, I heard the hum too. It pressurizes my room at 120Hz with about 50db at my listening position. We are talking amp system specific hum, not ground hum or transformer hum. I listen to classical music often, and in quiet passages the hum is intolerable. I also exchanged mails with Steve Deckert, but he couldn't offer me a remedy. I was able to sell the 300B in no time. I told the new owner all about the hum issue and said he should check the development forum on the issue. The reviewers never mentioned hum. I think that is strange, they certainly should have heard it. One of my goals for my rig has always been to reduce the noise level and increase dynamic range. Unfortunately, the Decware just didn't fit into my system. Oh well, that, I suppose, is just part of the hobby.

 

This sounds very consistent with my experience, and the ~50 dB of hum with your 100 dB speakers seems plausible given my ~58 dB of hum with 105 dB speakers?

 

On 2/22/2024 at 1:55 PM, Silverfoxvtx1800 said:

Never tried Aric amps but there is definitely great things said about his amps.i was really close to trying his gear but after burying a shorted out Primaluna tube in the backyard I decided to go SS with the Pass Labs  and very happy I did..the Primaluna EVO 400 I had was a constant problem after about 6 months of use and I use my gear more then the average bear being retired…the Decware I could hear the hum from my sitting position and being 70 that’s saying something…I took it to many friends systems and the same results…the Had amp had just a little hum that was bearable but my son could hear it so sold them and went to Primaluna…it had a slight hum but there was other noises too..after 4 hours of use it would make a noise like metal bending…weird..and you could hear weird little noises and tubes were shorting out. I am definitely happy with my Pass gear…I am sure we all have different experiences…for sure there are great tube amps out there…

 

FWIW, I used to have a primaluna evo integrated and got absolutely zero hum out of my La Scala AL5s!

 

On 2/22/2024 at 5:10 PM, mark1101 said:

Dumb question:  Have you tried a "cheater" plug (temporarily) just to see if lifting ground does anything?  Obviously, this is not safe and hopefully you are plugged into a GFI anyhow.

 

Another dumb question:  Have you tried shorting the inputs when you power up and have nothing connected on those inputs?

 

April 10, 2024 will be two years I have been waiting on a pair of SE84UFO.  I was around number 1250 when I purchased, and now I am around number 400.

 

How stupid.......I will never do anything like that again.  I hope I still have the same email and phone number when they finally build those things.  I hope I have the same address.  I hope I am still alive.  🙂

 

Yep, tried the cheater plug, and tried shorting the inputs. Neither changed the hum at all.

 

On 2/22/2024 at 7:56 PM, Edgar said:

 

Neither question is dumb; both are standard procedures in a case like this. Also check to see if the "hot" and "neutral" connections in the wall plug are reversed. One of these will do the job for you.

 

I have a (solid state) amplifier that only hums when the ground is lifted. I have another (solid state) amplifier that always hums unless I use one of these.

 

I got one of those outlet testers, and all my outlets are testing perfect  As for the second thing you linked, I think I have eliminated the possibility of any ground loop based on the fact that I get the same hum with nothing else plugged in except the amp, and nothing plugged into the inputs (other than a short).

 

Steve asked me to send him a video recording of a dB meter measuring the hum at listening position with the amp off (measuring ~41-43 dB of background noise in the room) and with the amp on (~57-58 dB of hum). Steve replied that he believes that there is no problem with anything, and that this is just the unfortunate consequence of pairing this amp with speakers of efficiency this high, possibly reinforced by placement and room effects. So far, this seems to be consistent with what I've heard with the few other experiences people have shared about me re: pairing this particular amp with super high efficiency speakers.

 

Nonetheless, if I'm missing anything and there is anything else I can try to bring the hum level down I am happy to hear it and try! I think that it's important to know whether or not we have conclusive knowledge that pairing this amp with 105 dB speakers doesn't work, as that is actionable information for other people on the Decware waiting list that may have already made such plans.

 

Thanks again for everyone's suggestions and input!

[Need Help: Decware + La Scala or KHorns]

17 hours ago, babadono said:

did we lose the OP @ThomBoh ?

Had to go to work, will update this evening

[Need Help: Decware + La Scala or KHorns]

1 hour ago, Khornukopia said:

 

Everything you have stated seems to indicate an amplifier problem, but 3 different units with the same hum makes me continue to wonder about the house wiring or the power from the street transformer. It is only fair to Decware that you become certain that your house is not the problem.

 

While we all think about the possibilities, can you post some picture of your amps? (This forum has picture file size limits, so it is best to downsize the pic file.)

 

I agree that with everything you're saying here. And yes, I agree that with the degree to which Steve has helped me troubleshoot so far, I definitely should make sure that I'm ruling out anything that would waste his time. Will post pics when I can.

 

42 minutes ago, mikebse2a3 said:

 

Reading through this thread it sure seems apparent to me that it is the Decware amplifiers are the source of your Hum Issue.

 

The question then becomes why are you experiencing it at such a high SPL level at the listening chair.

 

This makes me ask how you experience the Hum when you walk around in the room.? Do you hear it as significantly louder and quieter as you move around and also as you measure it with your SPL Meter?

 

I could see in an unfortunate situation where a possibility that room modes at 60Hz/120Hz could be coupling very efficiently with the loudspeaker and listening positions that would exasperate the inherent by design hum of these amplifiers.

 

Just a thought anyway and I hope you find a solution to this problem… 🙂

 

miketn

 

 

 

Good thought! I do feel pretty confident that 60/120 aren't major room modes based on the geometry, and the hum is definitely consistent as I walk around the room. Have not SPL meter'd walking around.

 

11 minutes ago, Shakeydeal said:

What is everyone saying in Steve's forum? If this is commonplace it surely is being discussed.

 

 

Here's the thread if you want to see all the info: https://www.decware.com/cgi-bin/yabb22/YaBB.pl?num=1708290398

 

Nobody there seems to be using speakers as efficient as La Scalas with these particular amps. Plenty of people there seem have experienced hum problems with their decware amps in different scenarios, but it seems like for the most part it was found that the problem was usually a ground loop or a bad tube or something obvious.

[Need Help: Decware + La Scala or KHorns]

1 minute ago, Khornukopia said:

 

 

Have you swapped back to one of those other amps since this problem started, plugged into the same wall outlet?

Good question, and yes  have also tried multiple different outlets in the room

[Need Help: Decware + La Scala or KHorns]

6 minutes ago, ned said:

I'm running a UFO through KHorns without any issue or noise at all. Here is the stupidly obvious question - have you ruled out the preamp?  If so, I think I would approach this in two ways - 1) unplug or turn off everything you can in the house and/or 2) use an extension cord to put your amp and pre amp on different circuits. I agree with everyone who mentions dimmers, LEDs, neons, fluorescents or anything that is using a transformer. Good luck. You should be enjoying amazing sound. 

 

Thanks for the suggestion. Again, there's no pre-amp here, and the hum is the same regardless of whether or not there is or isn't an input plugged into the amps, and regardless of whether or not there is literally anything else in that part of the house plugged into any outlet at all aside from just the amp. Also the hum is independent of the gain/volume setting on the amps, just as loud at 0 volume as it is at max. Could try unplugging literally everything in the house.

 

May I ask which UFO model you have? Would be a helpful data point  (edit: ah, I see it's the UFO2!)

[Need Help: Decware + La Scala or KHorns]

1 minute ago, Shakeydeal said:

Maybe I missed it, but you have tried other amps in your system that do not hum? At all?

 

 

Yes! I dont think I mentioned it. I have a Primaluna EVO 400 integrated and Naim uniti atom. No hum. It's only the Decware amps that are humming.

[Need Help: Decware + La Scala or KHorns]

6 minutes ago, Shakeydeal said:

The problem is that if you have any level of inherent noise in your system, most tube amps will bring it to the surface with horns. Especially if you have excessive gain in your preamp.

 

I used to think some level of noise in tube amps (especially in SET amps) was normal, especially with high efficiency speakers. After owning three Aric Audio amps, I have a different opinion. All of them are as dead quiet as 3 am. I mean "put your ear next to the speaker and think the amp is off" quiet. If Aric Kimball can make excellent sounding amplifiers with such a low noise floor, why can't others?

 

 

 

Broadly speaking I agree. But there's no pre-amp here (the 300B amp is an integrated), and the hum is identical regardless of whether or not a source is connected. Steve definitely could have eliminated the hum from his amps, but he chose not to for what he thinks are good reasons.

 

1 minute ago, JMeader said:

I have La Scala's with all new Crites drivers and the A4500 cross overs ( 105 db ). I waited 18 months for my Torii Jr V2 and yes I have a slight hum. I called Steve and and he suggested some different Tubes, which I got and it made no difference as to the hum issue.

 

My hum is slightly noticeable but not annoying for me, so will keep my amp.

 

Our music systems are for enjoyment, and I would agree that there are many great amps that do not seem to have the hum issue, so you have options to get back to enjoyment. 

 

The good news is Your Decware amps have a great resale due to waiting lists.

 

Enjoy Your Music

 

Yes, I will certainly sell it if I can't figure out a solution that gets me to a bearable amount of hum. But every single account I've seen so far of using one of these amps has been overwhelmingly positive, so it's worth it to try and make it work.

[Need Help: Decware + La Scala or KHorns]

3 hours ago, Flevoman said:

I had already mentioned it to you, but I'll mention it here as well. Both my Decware Zen triode from 2014 and my Decware Taboo III were completely silent on my AL5. These two amplifiers belong to the group of the quietest tube amplifiers I've ever had.

 

3 hours ago, Shakeydeal said:

I had a Decware Torii II on a pair of klipschorns a few years ago. While it was not as quiet as my Aric amps, it was nothing like you describe. I think you have a system issue and not an amp issue.

 

 

 

Thanks, both, for your sharing your experiences! So, from talking to Steve, I've learned that all of his amp designs are different in terms of their design targets and how much "inherent" hum they will have on super high efficiency speakers. He said, for example, that his 300B amp will have louder hum than his current SE84UFO25 amp, which will have more hum than his SE34I.5 amp, and so on. I don't know where the taboo sits on that scale. But I will say that I have an SE34I.5 as well in another system, and I tried it out with the La Scalas -- it was very quiet. This, however, doesn't mean that there's necessarily anything wrong with my SEWE300B or SE84UFO25s -- they are both designed to have higher level than hum than the SE34I.5... the question I'm trying to figure out here is just how much. Flevoman, your data point with the triode amp from 2014 is compelling, as that amp probably shares a lot more with my SE84UFO25 than the taboo. But still, might be too different to say. I might ask Steve about that!

 

As for it being a "system" issue, if you're referring to other components being the problem, I think I have ruled that out. The hum I get from the amps is identical regardless of whether or not any input device is hooked up to the amps. It is independent of whether or not anything else in the room is plugged in at all besides the amp. Am I missing something?

 

3 hours ago, jjptkd said:

 

 This is the first I've read about this I almost put myself on that list a few years back when the wait time was 8 months I believe? I cannot image the upset I'd have felt had I waited all that time to receive a hum master. Two year wait time is unacceptable in my book- an 8 month wait was for me back then but to each their own I guess. 

 

I waited about 2 years for my amp. Wait list now seems to be at least 4 :')

 

 

20 minutes ago, Marvel said:

Here is the document from Peavey about a balanced electrical system. It's basically a 120 volt transformer with a center tap that the connects to the downstream ground. each of the hot wires are then 60 volts. This is worth reading.

 

 

PWRDIST.pdf 89.6 kB · 1 download

 

 

Are you in your own home or a in a building that has a 208 volt three phase system for the building? If so, the way the 120 line is derived could be the problem.

This is a compelling read, thank you! I live in a single detached home, and I do not own it so I don't think I can really change the electrical system that's in place. But if I were able to point out that something is wrong with it, I could get it fixed.

 

Overall, again, I haven't come across anyone who has had the trouble with these specific amps that I am having, but I also haven't come across anyone who has paired these specific amps with these specific speakers, so, at this stage, the best I can do is to try and find someone who has. Because at this point, the manufacturer is pointing at my electrician, my electrician is pointing at my amp, and I have ruled out almost every common suggestion.. but do keep them coming!