In another thread, it was suggested I consider a new amplifier to drive my speakers, and more specifically, to drive my subs. However, I'm not sure what to look or listen for in order to really evaluate my amplifier. Is there something I can hear or measure to indicate it's not sufficient? I tend to evaluate on what sounds good, and the problem with that is I don't really know what is possible. My set-up is the best I've heard, but that's a statement on my limited experience and not a statement about the quality of my set-up.
Short of bringing home new amplifiers to test, is there something I can do to save time and money as I figure out what I need and compare options?
My set-up is below. The power amp is a four channel I'm currently running in bridge mode. The speakers are a non-standard set-up in that it's a pair bookshelf/satellite speakers (can be bought separately), each of which is paired with a matching sub.
Speakers: Usher S-520/SW-520 6moons audio reviews: Usher S & SW-520
Power Amp: NAD C-245BEE https://nadelectronics.com/wp-conten...ish-Manual.pdf
Pre-Amp: Antique Sound Lab Line one DT Antique Sound Lab Wave Line One tube preamp For Sale - US Audio Mart
DAC: Cambridge DACMagic Cambridge Audio Azur DacMagic D/A converter | Stereophile.com (I also have a PeachTree DAC IT that needs to be repaired. I don't really hear a difference in the two but convinced myself the DAC IT was better at one point in time.)
Short of bringing home new amplifiers to test, is there something I can do to save time and money as I figure out what I need and compare options?
My set-up is below. The power amp is a four channel I'm currently running in bridge mode. The speakers are a non-standard set-up in that it's a pair bookshelf/satellite speakers (can be bought separately), each of which is paired with a matching sub.
Speakers: Usher S-520/SW-520 6moons audio reviews: Usher S & SW-520
Power Amp: NAD C-245BEE https://nadelectronics.com/wp-conten...ish-Manual.pdf
Pre-Amp: Antique Sound Lab Line one DT Antique Sound Lab Wave Line One tube preamp For Sale - US Audio Mart
DAC: Cambridge DACMagic Cambridge Audio Azur DacMagic D/A converter | Stereophile.com (I also have a PeachTree DAC IT that needs to be repaired. I don't really hear a difference in the two but convinced myself the DAC IT was better at one point in time.)
What do you need to know about your amp? Frequency response? Distortion? Headroom? Output impedance?
I can help with headroom. Try my test here. Caveat: Of the NAD doesn't have enough headroom already, the test will be limited.
A Test. How much Voltage (power) do your speakers need?
I can help with headroom. Try my test here. Caveat: Of the NAD doesn't have enough headroom already, the test will be limited.
A Test. How much Voltage (power) do your speakers need?
In the bass only range, under damped response can be heard on tight bass drum tracks like ZZ Top Afterburner. Hits that go on too long, or different frequencies coming out at different times, are problems.
In the difficult treble area, really bad setups can make the voice letter S hiss like a jet plane.
To really discriminate on high frequency intermodulation distortion, I find top octave solo grand piano and high frequency bells can make a setup sound fuzzy. I use Peter Nero "Young & Warm & Wonderful When I Fall In love for the piano and Martin Denny Hawaii for the bells.
If your ears have the top octave cilia broken off by excessive noise over your life, you may not hear a difference.
Also listening to difficult tracks on headphones versus speakers can show wattage and clipping limits. Clipping makes things sound like a cheap transistor radio.
Have fun.
In the difficult treble area, really bad setups can make the voice letter S hiss like a jet plane.
To really discriminate on high frequency intermodulation distortion, I find top octave solo grand piano and high frequency bells can make a setup sound fuzzy. I use Peter Nero "Young & Warm & Wonderful When I Fall In love for the piano and Martin Denny Hawaii for the bells.
If your ears have the top octave cilia broken off by excessive noise over your life, you may not hear a difference.
Also listening to difficult tracks on headphones versus speakers can show wattage and clipping limits. Clipping makes things sound like a cheap transistor radio.
Have fun.
Listen to as many amps as you can in-home and in audio shops. I imagine being a transplant makes listening to other people's systems difficult. I'd say join a local audio club, but that could take a long time to develop a result. Point is, the only way to know is exposure. There really is no short cut. Specs only tell you so much and sometimes they are not even true.
Aside from that advice, I would say be really honest with yourself when listening to and auditioning gear. Keep asking yourself, does this fool me into thinking it's a real, living generated sound source, not just a recreated sound. Can this amp or sub-amp be tweaked to get me where I want to go?
Does it have the functionality I need? It's all about controlling that woofer.
Look for the lowest dip in impedance for the woofer cab and find an amp that can handle it and more.
Take advice from sales guys or gals sparingly. Try to weed through the BS.
Don't let them get you on an emotional trip and sell you something you don't want. It's very much like car shopping. 🙂
If money is no object, then you have a wide open field to pick from.
If money is no object, I feel sorry for you (in the nicest way possible. 🙂)
I think it's a tricky area when you get into really high end gear because of diminishing returns.
I have heard this sub amp (see link) myself and I know several audio guys that have used it. It's not pretty but it gets the job done well for the price. Has some serious specs. Parts-express has a 45-day return policy. I'm sure they'll take it back if you don't like it, if it's in good shape. Ask to be sure.
This amp can't do 2 ohms. It will shutdown.
Dayton Audio SA1000 Subwoofer Amplifier Rack Mountable
BTW- your Ushers are very nice. I have heard other models and they don't disappoint.
Good luck and I hope this helps in some way.
Vince
Aside from that advice, I would say be really honest with yourself when listening to and auditioning gear. Keep asking yourself, does this fool me into thinking it's a real, living generated sound source, not just a recreated sound. Can this amp or sub-amp be tweaked to get me where I want to go?
Does it have the functionality I need? It's all about controlling that woofer.
Look for the lowest dip in impedance for the woofer cab and find an amp that can handle it and more.
Take advice from sales guys or gals sparingly. Try to weed through the BS.
Don't let them get you on an emotional trip and sell you something you don't want. It's very much like car shopping. 🙂
If money is no object, then you have a wide open field to pick from.
If money is no object, I feel sorry for you (in the nicest way possible. 🙂)
I think it's a tricky area when you get into really high end gear because of diminishing returns.
I have heard this sub amp (see link) myself and I know several audio guys that have used it. It's not pretty but it gets the job done well for the price. Has some serious specs. Parts-express has a 45-day return policy. I'm sure they'll take it back if you don't like it, if it's in good shape. Ask to be sure.
This amp can't do 2 ohms. It will shutdown.
Dayton Audio SA1000 Subwoofer Amplifier Rack Mountable
BTW- your Ushers are very nice. I have heard other models and they don't disappoint.
Good luck and I hope this helps in some way.
Vince
First, I'm honestly not sure what sort of information I'm looking for because I'm not sure where to even start. I did run the test and measured 4.5 volts for the 220Hz tone.
In terms of going out and listening, how do you separate the amplifier from everything else? For example, at home, when I'm listening to a relatively sparse passage, it sounds really great, but as the music gets more intricate, I can almost feel some sort of distorting sound and can really hear the stereo imaging fall apart. This seems most pronounced in the mid to low ranges, but I'm not certain on that. I also notice a lot of grating highs, but I'm generally sensitive to those kinds of noises (hate tile floors for that reason). What I can't tell you, though, is how much of that is the result of my room (that's in the planning stages), my speakers, amp or other components.
And I'm not fortunate enough to say money is no object, but even if it were, just going out and buying top of the line stuff would take most of the fun out of it. I'll have to check out that amp, though...
In terms of going out and listening, how do you separate the amplifier from everything else? For example, at home, when I'm listening to a relatively sparse passage, it sounds really great, but as the music gets more intricate, I can almost feel some sort of distorting sound and can really hear the stereo imaging fall apart. This seems most pronounced in the mid to low ranges, but I'm not certain on that. I also notice a lot of grating highs, but I'm generally sensitive to those kinds of noises (hate tile floors for that reason). What I can't tell you, though, is how much of that is the result of my room (that's in the planning stages), my speakers, amp or other components.
And I'm not fortunate enough to say money is no object, but even if it were, just going out and buying top of the line stuff would take most of the fun out of it. I'll have to check out that amp, though...
How can you tell the amp from everything else? A lot of times you can't unless you have a base system you know and understand. You can't know until you have it in your home.
Maybe you just need to find a speaker forum that uses your speakers and subs and get an amp recommendation list going. You can start here on diyaudio.com.
One thing to be aware of with subs is the want to feel the sub sound. You have to feather it in there and not make it be prominent. Also, people have told me and have experienced it myself is when you get your highs and mids just right, as soon as you throw in the bass, it messes with the upper ranges. You then need to tweak all over again.
One of the most ignored aspect of an audio system is the room. The room is part of the system. There is also the placement of speakers in a room. Check out the Cardas web site. They have a diagram and easy calculation for speaker placement. There are others, but this might be a good starting point.
Always check out the first reflection points. Easiest way is to get one of those 3/4 length mirrors and place it on the side wall. When you see the speaker in the mirror from your seat, that's the first reflection point. Treat those areas with something that will absorb some of the reflection and just listen with and without it. Get a feel for the changes. Do you, like it or not? Try the same with the back and front walls.
when you make changes like that to the room, it could flush out other problems, but you start to get a feel of what the room is doing, so then you can map it out.
Maybe you just need to find a speaker forum that uses your speakers and subs and get an amp recommendation list going. You can start here on diyaudio.com.
One thing to be aware of with subs is the want to feel the sub sound. You have to feather it in there and not make it be prominent. Also, people have told me and have experienced it myself is when you get your highs and mids just right, as soon as you throw in the bass, it messes with the upper ranges. You then need to tweak all over again.
One of the most ignored aspect of an audio system is the room. The room is part of the system. There is also the placement of speakers in a room. Check out the Cardas web site. They have a diagram and easy calculation for speaker placement. There are others, but this might be a good starting point.
Always check out the first reflection points. Easiest way is to get one of those 3/4 length mirrors and place it on the side wall. When you see the speaker in the mirror from your seat, that's the first reflection point. Treat those areas with something that will absorb some of the reflection and just listen with and without it. Get a feel for the changes. Do you, like it or not? Try the same with the back and front walls.
when you make changes like that to the room, it could flush out other problems, but you start to get a feel of what the room is doing, so then you can map it out.
I have got caught out with amps with poor headroom.
For home use I would suggest at least+/- 45 volts DC power supply.
I have used +/-30VDC and it wasn't good enough.
Music can have very high transients.
This is an interesting question.
I don't think someone can say "What a great DA converter!" unless he really knows the other equipments associated with. Speakers and power amplifiers are somewhat easier to evaluate in unknown circumstances, but we really have to consider the synergy between amp and speaker. How to become an expert at the synergy between amplifier and speaker is a profound subject...
Step one, listen to setup with speakers, then with headphones. You can't check the subs that way but it will tell you what is possible on the low distortion front. Use 8 ohm headphones.
Difficult program material described above is key. When I was shopping in 1976, the Klipshorn dealer was using light jazz to demonstrate, ie trumpet, string bass, snare drum. Not difficult material. The AR dealer was using Simon & Garfunkle Wednesday 3AM album. Plunka plunka, words, not difficult material. I didn't buy any of those. I bought LWEIII because it had more bass, but didn't know enough to check high freq accuracy then. The tweeter blew up in a LWEIII before I learned the piano/bell checks.
What impressed me 1967-76 was Altec Lansing Voice of the Theater, which my band director spotted at a local movie theater. Those were great! no way I could afford them and the nearest dealer was Dallas 260 miles away.
My 1% HD tube amp was not a limitation until I bought some Peavey SP2-XT speakers about 2010. (Except when the e-caps or tubes were worn out, then the ST70 sounded "polite" because it had no power peaks. That could be measured on the output with an analog VOM. Not enough watts.) Before 2010 the speakers were always the limitation on distortion, as proved by the $35 headphones.
With the SP2-XT speakers I could really hear the difference between the 1% HD ST70 tube amp, and the .01% HD CS800s amp. My dynaco ST120 after serious mods (idle bias current control, more heat sink) approaches the CS800s in accuracy, but the side that has an AX6 board with 2 MHz Ft drivers (TIP41/42C) is a little less accurate on the highest sources. I picked the SP2-XT to drive 60 miles to test with a piano CD & Afterburner, because they looked like Voice of the Theaters. But were only $600 the pair.
Go to acoustic concerts and listen to some real instruments that should be reproduced accurately by your hifi. Steinway 9' grand piano, Yamaha grand, Kawai, Bechstein, all sound more alike than any two speaker series. Electronic instruments there is no standard sound, voice there is no standard. Voice, I heard Allison Kraus talking from 3' away walking from food booths to artist parking lot at a festival. She sounds a lot better on stage and CD; processed I suppose.
Have fun training yourself.
Difficult program material described above is key. When I was shopping in 1976, the Klipshorn dealer was using light jazz to demonstrate, ie trumpet, string bass, snare drum. Not difficult material. The AR dealer was using Simon & Garfunkle Wednesday 3AM album. Plunka plunka, words, not difficult material. I didn't buy any of those. I bought LWEIII because it had more bass, but didn't know enough to check high freq accuracy then. The tweeter blew up in a LWEIII before I learned the piano/bell checks.
What impressed me 1967-76 was Altec Lansing Voice of the Theater, which my band director spotted at a local movie theater. Those were great! no way I could afford them and the nearest dealer was Dallas 260 miles away.
My 1% HD tube amp was not a limitation until I bought some Peavey SP2-XT speakers about 2010. (Except when the e-caps or tubes were worn out, then the ST70 sounded "polite" because it had no power peaks. That could be measured on the output with an analog VOM. Not enough watts.) Before 2010 the speakers were always the limitation on distortion, as proved by the $35 headphones.
With the SP2-XT speakers I could really hear the difference between the 1% HD ST70 tube amp, and the .01% HD CS800s amp. My dynaco ST120 after serious mods (idle bias current control, more heat sink) approaches the CS800s in accuracy, but the side that has an AX6 board with 2 MHz Ft drivers (TIP41/42C) is a little less accurate on the highest sources. I picked the SP2-XT to drive 60 miles to test with a piano CD & Afterburner, because they looked like Voice of the Theaters. But were only $600 the pair.
Go to acoustic concerts and listen to some real instruments that should be reproduced accurately by your hifi. Steinway 9' grand piano, Yamaha grand, Kawai, Bechstein, all sound more alike than any two speaker series. Electronic instruments there is no standard sound, voice there is no standard. Voice, I heard Allison Kraus talking from 3' away walking from food booths to artist parking lot at a festival. She sounds a lot better on stage and CD; processed I suppose.
Have fun training yourself.
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For recordings that most people listen to, the voltage peaks are 16 to 18 decibels higher than the average music level. Classical is more, a lot of modern loud recordings are much less. To put that in power terms - peaks are generally 40X - 65X higher than average levels. In voltage, 6 to 8 times higher than average.
Lots of helpful advice. I'll definitely look at a pair of headphones. Any recommendations? I really don't want to spend much on that since I will only use it for these purposes. As discussed in the last paragraph, do I need 8 or 16 ohm headphones?
It seems it may be best, though, to start with the room. I've followed some of the guides mentioned here and believe I have them in a pretty optimal location according to those recommendations. However, I'm not accounting for my rather oddly shaped room with rather unique ceilings and other factors. I'll open a thread elsewhere on to see where I can make improvements.
Being a mathematician, I don't know why I find the power aspect so confusing. For example, I mentioned I ran Pano's test and measured 4.5 volts for the 220 Hz signal, but I really don't know what that tells me. I'm also wondering if my load is 8 ohms since my speaker configuration is rather odd. Each sub (8 ohm) receives power directly from the amp but are in a separate enclosure from the woofer/tweeter (8 ohm) which is powered by a jumper from a terminal on the sub to the rest of the speaker. What I don't know is if the sub to woofer/tweeter is series or parallel. Based on the woofer/tweeter, I'm guessing it's a series connection. Is there a way to check without having to open up the speaker cabinet?
It seems it may be best, though, to start with the room. I've followed some of the guides mentioned here and believe I have them in a pretty optimal location according to those recommendations. However, I'm not accounting for my rather oddly shaped room with rather unique ceilings and other factors. I'll open a thread elsewhere on to see where I can make improvements.
Being a mathematician, I don't know why I find the power aspect so confusing. For example, I mentioned I ran Pano's test and measured 4.5 volts for the 220 Hz signal, but I really don't know what that tells me. I'm also wondering if my load is 8 ohms since my speaker configuration is rather odd. Each sub (8 ohm) receives power directly from the amp but are in a separate enclosure from the woofer/tweeter (8 ohm) which is powered by a jumper from a terminal on the sub to the rest of the speaker. What I don't know is if the sub to woofer/tweeter is series or parallel. Based on the woofer/tweeter, I'm guessing it's a series connection. Is there a way to check without having to open up the speaker cabinet?
Sometimes moving the speakers an inch or two makes a difference. I've seen guys who build rooms and consult on sound systems use lasers to pinpoint toe-in to the listening position.
It tells you that at the volume setting you used for the test, the sine wave at 12dB below peak results in 4.5V at your speaker. From that you can know that the loudest sine signal will be 9dB higher. 9dB because the loudest sine wave in digital is 3dB RMS below peak. 12-3=9.
4.5V X 9dB = 12.7V. You need an amp that can supply at least 12.7V RMS to your speakers. Call it 15 volts just to be on the safe side.
Your sub almost certainly has a low pass filter (we would hope). That means its impedance is very high above that low pass point. Above the crossover point it doesn't contribute much to the amp's load. However, if your woofer is not high pass filtered, it is in parallel with the sub thru the sub's operating range. Meaning the load is likely 4 ohm up to where the sub rolls off, then 8 ohm above that. Nothing a good solid state amp can't handle. But it does mean twice the current needed in the low end.
😱 Guilty
Unsurprisingly it didn't take long to drift away from the sound of the amp. This is the component that has the least effect on the sound of your set up. There is very little to choose between the sound of any decent amp, they pretty much do the job near as damn it perfectly
Best way to remove room effects is soft sound damping materials on the walls floor & ceiling. Standing waves are what messes up speaker response, and soft material on the walls floor & ceiling inhibits sonic reflections.
I use carpet, bookshelves & LP shelves, polyurethane stuffed furniture, since I'm a media packrat. A piano & organ are more reflective but irregularly shaped. Clean freaks can use polyurethane batting sold at music supplies and home stores. The Sound deadening material used for studios. Also drapes fabric wall hangings etc.
Also look at concert halls. My music/living room is 14' wide, 11' high, 33' long, like Wien Philharmonica hall. Speakers are at the narrow end spaced 6' apart. Listening position is a polyurethane stuffed chair 20' from narrow in. Also the kitchen table chair 30' away. Wedge shaped halls are known disasters after several notable failures like Lincoln Center first past. SBJHS Junior high auditorium, wedge shaped with brick walls and concrete floor, was a reflection disaster. My best friend had a heptagonal bedroom with Bose 9's on one side. I never liked the sound there.
I lucked out that the shotgun typed bungalo built all over Kentuckyana in the 1930's had this room arrangement. It was cheap, less than 2 years pay when I bought. The wall was knocked out between living room & dining room by previous owner, and the kitchen tacked on the back lets the horn speakers fire highs right at me when I'm eating, 30' away. SP2-XT are designed for crowds at that distance. I have them on stands near the ceiling, per the datasheet, as highs project slightly down - at my easy chair.
I bought Koss full cover headphones at K-mart 40 years ago for $35. The piano test says they are pretty good. I would guess sennheiser shure & audio-technica have as much investment in pleasing the customer. I've had other generic ones that had too much bass and or muddy treble. People are bass mad these days. I wouldn't go below about $30 the pair.
I use carpet, bookshelves & LP shelves, polyurethane stuffed furniture, since I'm a media packrat. A piano & organ are more reflective but irregularly shaped. Clean freaks can use polyurethane batting sold at music supplies and home stores. The Sound deadening material used for studios. Also drapes fabric wall hangings etc.
Also look at concert halls. My music/living room is 14' wide, 11' high, 33' long, like Wien Philharmonica hall. Speakers are at the narrow end spaced 6' apart. Listening position is a polyurethane stuffed chair 20' from narrow in. Also the kitchen table chair 30' away. Wedge shaped halls are known disasters after several notable failures like Lincoln Center first past. SBJHS Junior high auditorium, wedge shaped with brick walls and concrete floor, was a reflection disaster. My best friend had a heptagonal bedroom with Bose 9's on one side. I never liked the sound there.
I lucked out that the shotgun typed bungalo built all over Kentuckyana in the 1930's had this room arrangement. It was cheap, less than 2 years pay when I bought. The wall was knocked out between living room & dining room by previous owner, and the kitchen tacked on the back lets the horn speakers fire highs right at me when I'm eating, 30' away. SP2-XT are designed for crowds at that distance. I have them on stands near the ceiling, per the datasheet, as highs project slightly down - at my easy chair.
I bought Koss full cover headphones at K-mart 40 years ago for $35. The piano test says they are pretty good. I would guess sennheiser shure & audio-technica have as much investment in pleasing the customer. I've had other generic ones that had too much bass and or muddy treble. People are bass mad these days. I wouldn't go below about $30 the pair.
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How are you going to stuff all those worms back into that can you just opened? I don't envy you the task.
I thought most people knew this to be a fact.......I guess I mean if you want an amplifier to amplify that's pretty easy, if you want a sound effects box, now that's a different matter 😉🙂
That's the same old trope we hear over and over. Doesn't make it anymore believable.
And that "effects box" meme is wearing thin.
And that "effects box" meme is wearing thin.
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