What audio system do you have, or plan on getting?

[drogulus]

Nice! I don't care much for the color, but I bet it's a smoker.

     The amp dates from 1972. They were produced throughout the '70s and the brand went through several changes of ownership after. Nothing made after the '80s has any relation to the original designs.

     

[Mirror Image]

     The amp dates from 1972. They were produced throughout the '70s and the brand went through several changes of ownership after. Nothing made after the '80s has any relation to the original designs.

   

Ah, very interesting. Thanks for the information. I don't know much about the company, but I love the amp I own.

[greg]

Thought I'd update.

The advice given by DavidW was very helpful for some starter tips.

Ultimately, figured out what works the best for my situation, what I wanted, and feel pretty satisfied. My budget ended up actually being much larger for this (nearly $5k in total).

Rotel A14 MKII - amplifier
Rotel CD14 MKII - Cd player
Kef LS50 Meta - bookshelf speakers (w/stand)

Was initially going to go with Cambridge stuff, researched pretty hard into their product line, but many smaller reasons why I decided against it. Also, just a preference to get new stuff was a factor in the decision.



Oh, I also mentioned earlier about the Mesa Boogie Dual Rectifier Amp- got that, too, finally. Paired with my EVH 5150 6L6 and my crazy double pedal board. And of course, the ability to finally actually play it now that I'm out of the apartment life. Sounds perfect.

[staxomega]

Kef LS50 Meta - bookshelf speakers (w/stand)

Nice, I'm interested in hearing good coaxial speakers, Genelec "The Ones" series are on my to hear list.

[staxomega]

This is part of the Quad mythology. 

No. The Quads were invented decades before something like a Klippel or things like constant directivity research existed. I would trust a single frequency measurement at the listening position to tell me something about room nulls and a rudimentary frequency response beyond that. I would apply this to every single speaker.

Loudspeakers cannot reproduce the midrange of piano played at forte or fortissimo accurately without enormous amounts of power, and many drivers do not have the physical capacity to reproduce the piano accurately.  So we are indeed left with anecdotes.

This is also wrong. Something like a K402 waveguide at 105 db/w when used active isn't going to need "enormous amounts of power" to play fortissimo. Combined with the room gain one can get by with any reasonable amplifier that doesn't need to be an arc welder. Or just running an active box speaker system a tweeter (vs a bass driver) is not going to need enormous amounts of power either, it will need a protection circuit or you risk frying it, hence why you'd do the rational thing and just use a lower power amplifier.

Out of curiosity, were Quad ESL 57s among the speakers tested? 

They weren't, but it's easy to buy speakers that were designed around principles that Toole's research points to, which is where my current interest is, not in some product of the past.

Beyond that, the emphasis on flatter frequency response is more or less a given for good sound for many speakers, though some designers pursue other objectives.

Old fashioned thinking. There is far more to it than just flat frequency response which is an obvious one. Moreover your rather vague "flat frequency" response doesn't address how this was measured; flat in an anechoic chamber great. Flat in a listening room, no. Assuming the former this should be the absolute bare minimum for high fidelity, constant directivity should be prioritized just as much. We need the reflected sound to be timbrally similar to the direct sound.

Also, active crossovers have been used for decades, especially in studio gear, and they typically sound better than passive crossovers.  DSP may or may not represent an improvement.  That would require comparative measurements and listening. 

Agree, though the companies I know of still using active electronic crossovers with no DSP solutions, ie ATC are stuck in the past building speakers around old fashioned principles and ignoring other very important areas; hence my interest in DSP with the likes of D&D, Kii, and Genelec. Correct that DSP in itself is not the end all be all.

In other words, you don't know.

If you're not going to point out specifically what I posted that was incorrect, I'm going to assume this is further deflection from someone that just learned about Toole yesterday.

The comb filtering is there, but you don't really have two point sources interfering at the listener's location. In addition to the primary sources you have multiple reflections arriving at your ear from various surfaces in the room, which will never be symmetric, so at no frequency will you have two waves out of phase producing complete cancelation.

This is basically "the room is going to mess things up anyway" which can be true, but that doesn't mean we should throw everything out. The radiation pattern at midrange and treble frequencies is going to be somewhat spherical which includes the vertical axis (obviously narrowing the higher you go) where cancellations will occur. There are measurements with ribbon super tweeters causing deep nulls/cancellations that I would hope would be audible to people, but you know I'm more likely to read about how this expensive box "opened things up" and made everything so much better.

I have some of these saved from another forum, let me see if I can find the measurements.

[Todd]

No. The Quads were invented decades before something like a Klippel or things like constant directivity research existed. I would trust a single frequency measurement at the listening position to tell me something about room nulls and a rudimentary frequency response beyond that. I would apply this to every single speaker.

Yes, it is part of the mythology.  Audiophilia is filled with mythology and people who defend said mythology.

This is also wrong. Something like a K402 waveguide at 105 db/w when used active isn't going to need "enormous amounts of power" to play fortissimo.

You are correct, exotic, high sensitivity horns can produce high volumes with less power.  I always forget about those and will happily continue to do so. 

Flat in a listening room, no.

I guess this represents new fashioned thinking.

If you're not going to point out specifically what I posted that was incorrect, I'm going to assume this is further deflection from someone that just learned about Toole yesterday.

It was specific to your assertion about needing elaborately expensive gear for measurements.

[staxomega]

You are correct, exotic, high sensitivity horns can produce high volumes with less power.  I always forget about those and will happily continue to do so. 

It's a constant directivity waveguide designed with sound science principles, most of their owners use Crown amps. Earl Geddes (free, no book purchase needed: http://www.gedlee.com/Papers/directivity.pdf) also uses waveguides and so does nearly every high fidelity design with the tweeter to match the radiation pattern of the mid or mid/woofer at that drivers upper crossover point. Alternatively you could do something more exotic like using two different sized midrange drivers with a tweeter so there are no directivity mismatches at any of the crossovers.

High, sensitivity exotic horns is something like Goto, Avant-garde, etc that people are pairing up with SET amps.

I guess this represents new fashioned thinking.

No, flat in an anechoic chamber would basically be -2-3 db at 20 Khz in a listening room. Hence why no one would actually want flat response in a listening room. It's good to design loudspeakers that measure flat on axis in an anechoic chamber.

It was specific to your assertion about needing elaborately expensive gear for measurements.

To design high fidelity loudspeakers, yes*. To design something an owner would be content with, no.

* if one wants to carry their speakers out to a quiet field, take dozens of measurements every certain number of degrees, adjust, measure, adjust, alright you can get by with a calibrated mic and reasonably priced software. Something tells me very few people or companies do this. Likely not people or companies that mention what type of drivers they're using.

[Todd]

most of their owners use Crown amps

How do you know?

I like the wordier description for a horn speaker.  It's good marketing.  Looks sciency.

[Holden]

My venerable old McLaren 150B Amp which I've had since 1988 is now showing signs of failure so it's time to get a new integrated amp. The A150B was quite advanced for it's time, even with only 50W per side but I'm sure that modern technology has come a long way since then and virtually anything I buy will be superior in sound quality.

With that in mind and no need to fill a large room with I'm going down the budget route. I also do a lot of headphone listening via my PC so the amp will not be (in deference to my neighbours) my main system but will still get quite a bit of use. There are two choices for me:



or



The Rotel makes sense as it doesn't have any extra bling that I would not need to use. All the money has been poured into getting the best sound and I also have a Rotel C11 CD player so synergy becomes a factor.

The NAD, at a similar price and specs is also a strong contender.

I also looked at Cambridge AXA35 , Pro-Ject S2 BT (both probably underpowered and I don't need BT as I have a wifi streamer) Marantz 6006, and Yamaha A-S301

I'm off on vacation tomorrow and will wait until I get back before pulling the pin.

[Todd]

Between the Rotel and the NAD, I'd go with the NAD.  I bought a C 372 about twenty years ago, and it is still going strong for my daughter.  Ultimately, either one would be fine.  It may be best to just buy the lowest price model.

[Holden]

Between the Rotel and the NAD, I'd go with the NAD.  I bought a C 372 about twenty years ago, and it is still going strong for my daughter.  Ultimately, either one would be fine.  It may be best to just buy the lowest price model.

The NAD and the Rotel are the same price with basically the same features so deciding will be hard.

[71 dB]

My venerable old McLaren 150B Amp which I've had since 1988 is now showing signs of failure so it's time to get a new integrated amp. The A150B was quite advanced for it's time, even with only 50W per side but I'm sure that modern technology has come a long way since then and virtually anything I buy will be superior in sound quality.

There wasn't been much improvement in sound quality in amps. They had very good sound in 1988 so there is not much to improve.

[Todd]

The NAD and the Rotel are the same price with basically the same features so deciding will be hard.

I'd go with aesthetics at that point.  Which do you prefer looking at?

[Fëanor]

There wasn't been much improvement in sound quality in amps. They had very good sound in 1988 so there is not much to improve.

On the contrary, there has been a large leap in amp quality with the advent of ultra-low distortion amps, notably class D amps from Hypex and Purifi.

FWIW, NAD has models that exploit one or the other.  For example the NAD C 399 integrated amp/streamer uses Hypex nCore models while the NAD M 33 integrated amp/streamer uses Purifi  "Eigentakt" modules.

However neither the pictured Rotel RA-10 nor the NAD C 316BEE use these technologies, (though they are likely decent amps in their own right).

[71 dB]

On the contrary, there has been a large leap in amp quality with the advent of ultra-low distortion amps, notably class D amps from Hypex and Purifi.

FWIW, NAD has models that exploit one or the other.  For example the NAD C 399 integrated amp/streamer uses Hypex nCore models while the NAD M 33 integrated amp/streamer uses Purifi  "Eigentakt" modules.

However neither the pictured Rotel RA-10 nor the NAD C 316BEE use these technologies, (though they are likely decent amps in their own right).

Yes, technically there has been, but audibility of those things is questionable. Once the distortion gets below the threshold of audiblity lowering it further doesn't make the sound any better for the ears. Only for analysers.

The main benefit of new digital amp modules is their capability to produce a lot of power from small units because they waste do little power. So, powerful amps can be smaller, spend less electricity and run cooler, but for human ears the sound quality is pretty much the same as a few decades ago.

The main source of distortion is speakers. The distortion of the amp is insignificant (unless we are talking about e.g. tube amps).

[Fëanor]

Yes, technically there has been, but audibility of those things is questionable. Once the distortion gets below the threshold of audiblity lowering it further doesn't make the sound any better for the ears. Only for analysers.

The main benefit of new digital amp modules is their capability to produce a lot of power from small units because they waste do little power. So, powerful amps can be smaller, spend less electricity and run cooler, but for human ears the sound quality is pretty much the same as a few decades ago.

The main source of distortion is speakers. The distortion of the amp is insignificant (unless we are talking about e.g. tube amps).

There is still debate about what the threshold of audibility is -- I've hear -120 dB quote as the absolute threshold.  There has been even more debate how audible the different amplifiers actually are.

True, of course, that speakers produce much more distortion than typical amplifiers.  Notwithstanding, I've feel I heard differences between amplifiers.  For a number of years I used a Pass Labs X150.5;  it was certainly a pleasant sound amp.  However when I when to a Purifi 1ET400A-based amp I heard a distinct increase in transparency and dynamics.  My imagination?  Maybe but I think not.

[Valentino]

This is the frequency response of my left speaker with individual drivers plotted, measured in the listening position. Sounds right and everything you see is intended.

[71 dB]

There is still debate about what the threshold of audibility is -- I've hear -120 dB quote as the absolute threshold.  There has been even more debate how audible the different amplifiers actually are.

The threshold of hearing is one thing. It means how quiet sound are audible when a person has stayed a long time in an extremely quiet place (anechoic chamber). The threshold varies a lot with frequency, but hearing is at its most sensitive at about 3.5 kHz where the threshold of hearing can go a few decibels below zero of sound pressure level. However, any louder environment such a living room raises the threshold of hearing the more the higher the sound pressure level. When listening to music for example, auditory masking happens. Lossy formats such as mp3 take advantage of this. The idea is that the music information that is thrown away isn't noticeable, because of masking. Yes, people can hear things especially at lower bitrates, but then again at 128 kbps mp3 contains barely 10 % of the original information!

There is also a lot of debate whether the Earth is flat and whether vacciness contain nanotechnology to control and track people, but that doesn't mean those issues are "unsolved" for sane people. Audio is a business and as long as there are gullible snake oil believers, there will be snake oil seller to cash in, and purposedly generating doubt about subjects such as audibility of microscopic things is an effective way to keep the money flowing in.

If amps are so easy to tell apart, how on Earth is it always to difficult to demonstrate it in proper listening tests?

True, of course, that speakers produce much more distortion than typical amplifiers.  Notwithstanding, I've feel I heard differences between amplifiers.  For a number of years I used a Pass Labs X150.5;  it was certainly a pleasant sound amp.  However when I when to a Purifi 1ET400A-based amp I heard a distinct increase in transparency and dynamics.  My imagination?  Maybe but I think not.

A properly designed amp generates so little distortion (when driven at power levels it can easily handle) that nobody can hear it, while speakers can easily generate audible distortion when pushed a little bit, especially at low frequencies. The system of amp + cable + speaker can have an effect* on the sound if there is mismatch. It is possible you have heard something like this, but generally it is wise to assume most of the differences you think you hear are a product of placebo and are likely to vanish in proper listening tests.

* If the speaker impedance is very low at some frequencies and the cable is long/thin, there can be audible effects with frequency response and damping. Some amps can be unable to drive certain demanding speakers properly. In these cases it is not the amp, it is the mismatch between the amp and speakers. Demanding speaker require capable amps!

[staxomega]

How do you know?

I like the wordier description for a horn speaker.  It's good marketing.  Looks sciency.

This is once again wrong. These are designed for professional theater use, people just happen to use them in their home because they saw the superb directivity with them and the designer has also written about it as one of the goal's when it was being designed. As for why most people are using Crown amps it's because the electronic crossovers are set for the Crown amps via dampening down the sensitivity towards those amps' gain (since they are pro audio amps they might not be the exact 26 dB "norm") and EQ. I'm sure people are free to do what they please, but people using them tend to know audio.

This research with controlled directivity "horns" (more accurately waveguides since in the old days a horn was primarily to raise sensitivity with WW I era amps being able to put out barely a watt of power), started in the late 70s or early 80s (don't care enough to look through the patents) in pro audio use. We now know why constant directivity is desired via Toole's research but they were onto it before that.

Danley speakers are another example of these pro audio constant directivity horns, mostly used in stadium installs that people are now using in home theater setup because of the controlled directivity.

And you can even the waveguides on small speakers like JBL LSR 306: https://www.audiosciencereview.com/forum/index.php?threads/jbl-306p-mk-ii-review-studio-monitor.18505/

I have these in my office, given they were ~ $150 each and limited by what they could do at that price, the directivity match is not flawless at the crossover but the measurements punch above their price.

[Todd]

As for why most people are using Crown amps

Again, how do you know? 

It is always nice to see passionate audiophile types go on about things no one cares about, like horns.