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Fortelover
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4 hours ago, Fortelover said:

Considering decware se341.5. Using forte 1 speakers. I figure Miles Davis and London Philharmonic sound good, but what about Joe Satriani and Slayer. Tube amp with heavy music. Any thoughts?

I'm listening to the reissued self-titled Metallica album (the black album) on an Elekit TU-8200 in ultralinear mode right now right after finishing the HDTracks 96/24 release of Dark Side of the Moon.  No problem with tubes per se, and Decware has a great reputation. Go for it.

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I stay as far away from any company that states using cryo treated beeswax caps as a performance part. Coupling capacitors are of such low impedance compared to the circuit you don't encounter phase shift unless they are undersized and suffer low frequency roll-off and at those frequencies you will encounter phase shift. Coupling caps low impedance means there really is no signal ACROSS them, which means they really are not doing anything to the signal at all. Since there is no signal across them they do not add any distortion. I have tested so many coupling capacitors and overlaid the results and there is no difference between electrolytic and any boutique capacitor you can find me. In fact, the only different with these extremely large beeswax capacitors is they will actually increase noise which was the only thing I saw different. Our local audio group did blind listening tests and nobody yet has been able to reliably tell the difference between any coupling capacitors. I know this is a heavily debated topic but there are other capacitors in the signal path that actually make a difference. People believe because the coupling capacitor is in series that the signal has to pass through it like a water through a filter which just is not correct. It is when a capacitor has the whole signal across it's terminals, like a capacitive load, the capacitor qualities then come into play. I do not expect non-engineers to understand exactly how capacitors function as it is very complex but cryo treated snake oil capacitors are just not needed, sorry.

 

The decware amp you are looking at is 6 watts. The forte is a 98db speaker at 1 watt. To have enough dynamic headroom you need 20db, will this be enough for you? Depends on average listening levels. The 6 watt amp will roughly bring you to 106db at 1 meter away, this puts your average listening requirements down to 86db. If you average 86db or less then it should be fine for you. Unless you are running a class A2 amplifier you never want to run it near max output so to be safe maybe say 84db average. You can download an app that will tell you the db level of your average listening volumes, I suggest you figure this out before looking at amplifiers so you can at least find out how much power you will need to have adequate headroom.

 

Decware does not state any distortion specifications. It does state that it uses zero negative feedback. I will go ahead and say that this may not be the amp for you if you want to listen to complex music at even moderate sound levels. It will just have too much distortion for complex music and without any negative feedback the damping factor will not be great, you will get what they call "one note" boomy bass most likely with this setup so bass heavy and complex music tones will not be great.

 

This particular amp is marketed to people that think feedback is bad, there is a myth that "no feedback' amps are superior but in this case I do not get the warm fuzzy feeling that no feedback is a good idea. Well, unless you listen to very simple music like vocals, chamber, simple acoustic, piano, etc.... Start cranking Metallica after a few beers and it just will not hold up to well.

 

I say figure out your average listening levels and report back. Download the app and let us know, then we can roughly give you a power rating you want to shop for and go from there.

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6 hours ago, captainbeefheart said:

Our local audio group did blind listening tests and nobody yet has been able to reliably tell the difference between any coupling capacitors.

 

Any quality electrolytic that meets the design spec is fine.  Agree

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That method used in that video about how much power is needed is grossly inaccurate. He is using a digital multimeter that is not fast enough to display any reasonable information, with actual program material like he played it will just bounce around readings.

 

The best way is to use a digital source while listening to music and make note of where the volume control is at. This should be the loudest you will ever listen to music. Next record a 240Hz sine wave at -20db and play it through the system with the same digital source used for the listening test. Take your measurement at speaker terminal. We know the loudest a digital source can get is 0db, since you are measuring a constant sine wave at 240Hz the digital meter will be accurate. We also know that -20db is a gain of 10x. So say you measured 700mV, you know that the largest transient in the recording you were listening to while doing the listening test will be .7*10=7v. That is 6.125 watts into 8 ohms. This method is going to be the closest way to measure your power needs and have it be accurate.

 

Jim I agree, a Fisher 400 would be great!!

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Considering decware se341.5. Using forte 1 speakers. I figure Miles Davis and London Philharmonic sound good, but what about Joe Satriani and Slayer. Tube amp with heavy music. Any thoughts?
I use a restored HH Scott 222c for all my mellow stuff. I agree.....big time sweetness. It does great with the heavy stuff as well but when it comes to Slayer, Metallica, Pantera etc......I much prefer high powered solid state. It brings out the aggressive qualities of that type of music that low a powered tube amp just cannot. Think live concert.

Sent from my SM-G991U using Tapatalk


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20 hours ago, captainbeefheart said:

I stay as far away from any company that states using cryo treated beeswax caps as a performance part. Coupling capacitors are of such low impedance compared to the circuit you don't encounter phase shift unless they are undersized and suffer low frequency roll-off and at those frequencies you will encounter phase shift. Coupling caps low impedance means there really is no signal ACROSS them, which means they really are not doing anything to the signal at all. Since there is no signal across them they do not add any distortion. I have tested so many coupling capacitors and overlaid the results and there is no difference between electrolytic and any boutique capacitor you can find me. In fact, the only different with these extremely large beeswax capacitors is they will actually increase noise which was the only thing I saw different. Our local audio group did blind listening tests and nobody yet has been able to reliably tell the difference between any coupling capacitors. I know this is a heavily debated topic but there are other capacitors in the signal path that actually make a difference. People believe because the coupling capacitor is in series that the signal has to pass through it like a water through a filter which just is not correct. It is when a capacitor has the whole signal across it's terminals, like a capacitive load, the capacitor qualities then come into play. I do not expect non-engineers to understand exactly how capacitors function as it is very complex but cryo treated snake oil capacitors are just not needed, sorry.

 

 

A discussion about Economics in a tube amplifier inquiry thread seems problematic and inappropriate.

 

Your post actually makes the argument for the beauty of hand made boutique items... If I wanted furniture that functions, I might shop at Ikea... If I wanted a piece of furniture that is unique that also functions, I certainly would not go to Ikea.

 

If there is NO DECLARABLE difference in your personal tests, why not use boutique items... economics.

 

I have to roll my eyes every time someone makes your exact observations...

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21 hours ago, captainbeefheart said:

"I stay as far away from any company that states using cryo treated beeswax caps as a performance part"

 

It's marketing. If I were in the market for a tube amp, I would certainly entertain a Decware amp over amps made in other countries (China for example). Do I agree with all the buzz around Decware? No, but you can tell they are quality amps. Fortunately, I can design and make my own amps.

 

I agree from a technical point that you shouldn'r be able to hear any differences, but a lot of people claim to be able to hear what I can't. One thing I do believe is that we all hear differently and can hear different elements of music that equipment cannot measure.  

 

 

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21 hours ago, captainbeefheart said:

 

 

unless you listen to very simple music like vocals, chamber, simple acoustic, piano, etc.... Start cranking Metallica after a few beers and it just will not hold up too well.

Very simple...  and then compared to Metallica? Wow

 

21 hours ago, captainbeefheart said:

Coupling caps low impedance means there really is no signal ACROSS them, which means they really are not doing anything to the signal at all. Since there is no signal across them they do not add any distortion.

 

I am not an engineer, but if there is no signal, why are they there at all? But if there is a signal, something is happening across them.

 

 

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56 minutes ago, michaelwardjoines said:

I am not an engineer, but if there is no signal, why are they there at all? 

 

 

To block DC. In tube amplifiers there are large amounts of DC on the plates of tubes and they must not get to the grids of the next tube. Necessary evil. 

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3 hours ago, Schu said:

 

 

A discussion about Economics in a tube amplifier inquiry thread seems problematic and inappropriate.

 

Your post actually makes the argument for the beauty of hand made boutique items... If I wanted furniture that functions, I might shop at Ikea... If I wanted a piece of furniture that is unique that also functions, I certainly would not go to Ikea.

 

If there is NO DECLARABLE difference in your personal tests, why not use boutique items... economics.

 

I have to roll my eyes every time someone makes your exact observations...

 

You overlooked the part about the increased noise floor differences. The boutique capacitors especially the Jupiter ones mentioned are much larger in size compared to capacitors actual engineers chose to use and the physical size is what picks up more noise. It is not really just a economical issue, noise is certainly considered part of performance. The capacitors named by decware showed the higher noise floor when tested.

 

If it does only come down to price and performance is exactly the same, I completely agree with you. If you just want or like fancy expensive "boutique" things then that is totally cool also and I have zero problems with that. People strive for originality and want to be different from the pack. I guess my only gripe is that many of these companies that install these boutique components claim they have performance enhancing quality which in a coupling capacitor application is going to be BS 99% of the time, or worse they add more noise which I would think nobody would want.

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15 hours ago, captainbeefheart said:

 

You overlooked the part about the increased noise floor differences. The boutique capacitors especially the Jupiter ones mentioned are much larger in size compared to capacitors actual engineers chose to use and the physical size is what picks up more noise. It is not really just a economical issue, noise is certainly considered part of performance. The capacitors named by decware showed the higher noise floor when tested.

 

If it does only come down to price and performance is exactly the same, I completely agree with you. If you just want or like fancy expensive "boutique" things then that is totally cool also and I have zero problems with that. People strive for originality and want to be different from the pack. I guess my only gripe is that many of these companies that install these boutique components claim they have performance enhancing quality which in a coupling capacitor application is going to be BS 99% of the time, or worse they add more noise which I would think nobody would want.

Much like fishing lures. Many times they catch more fisherman then they do fish. Sure are pretty though. Klipsch now uses older technology polyester vs polypropylene caps because they are plenty good enough. Some even consider them better sounding. 

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4 hours ago, henry4841 said:

Much like fishing lures. Many times they catch more fisherman then they do fish. Sure are pretty though. Klipsch now uses older technology polyester vs polypropylene caps because they are plenty good enough. Some even consider them better sounding. 

 

I am going to have to steal that fishing lure quote from you!! So true.

 

 

We have been using Panasonic ECQE non-inductive metallized polyester capacitors for a while now. Very tight tolerances, low esr, low DF, no shock or audible noise or piezoelectric effects. Just fantastic capacitors really.

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