Amp question

[tmurnin]

I’m considering adding an amp to my 2 ch system, currently powering Salk Song Towers with an NAD T758. I’ve never been thrilled with the sound out of this setup - always thought it sounded a bit “thin” if that makes sense. I emailed Jim Salk and he suggested that the NAD may be a bit underpowered for the speakers and suggested adding an amp.

A local store has an open box special on a Rotel RB 1572 for $500. That’s a class D amp, but I don’t know if that should concern me or not. Couple questions:
1. Do people think adding an amp would help with the overall performance of the system?
2. Thoughts on the Rotel? I’m not looking to spend a ton of money here so open to alternatives but want to keep the budget under $1k for an amp

 

[mazersteven]

The Rotel seems like a nice Amp.

Also the Outlaw Audio 2220 Monoblocks are solid

Model 2220

Mono? Mini? Micro? Magnificent? Whatever that M is, this is one UNREAL little single-channel amp. 200 Watts (conservatively!) into a 3-inch chassis with balanced input stage to offer Common Mode Rejection! MANUAL See Front Panel Huge See Rear Panel Huge

outlawaudio.com

 

[ryanosaur]

Maz took the words right outa my typing fingers.
I love the Outlaw Monoblocks. An insanely great value for the amplification. Not much comes close.
I use mine with other Dennis Murphy designed speakers, too.

Depending on your goals, some Class D amplification is pushing the bounds of performance quite nicely. If you want to consider it, look at anything built around Hypex N-Core or Purifi modules. The ATI Class D amps use Hypex, for example. Also, Nord, Apollon, KJF... all build various Amps using these modules.
For example, here is a dual-mono amp from Nord:

Nord One NC500DM Dual Mono | nordacoustics

Our entry level stereo power amplifier with twin Hypex NCore NC500’s, twin Hypex SMPS1200A700 PSU’s and cut down (no Sparkos discrete Voltage regulators) REV C buffers with OPA1612 Op-Amp in a true Dual Mono design incorporated in a single stereo case. Same sound quality as the Mono Blocks.

www.nordacoustics.co.uk

And an upgraded version that includes an additional OP Amp stage:

Nord One NC500DM MKII Dual Mono Stereo Amp | nordacoustics

True Dual Mono Amplifier with 2 x Hypex NCore NC500, 2 x Hypex SMPS1200A700 PSU's and 2 x Nord UP REV D Input Buffer Boards Board with choice of OP Amps in a Stereo Case. Rev D will also accept previous 8 pin Sparkos and Sonic Imagery OP Amps.

www.nordacoustics.co.uk

You can also DIY Hypex and Purifi Amps. I think the Hypex NC400 is the most direct and simple construction to work with here as you need 1 each Amp Module per channel, and 1 or 2 SMPS modules like the SMPS 600N400 depending on whether you want a Stereo Amp or Dual Mono construction. Chassis options are available from Ghent Audio like this one here:

ghentaudio --- NCORE-SE(200W) Hypex & NCore NC400 NC1200 Stereo Case-kit

Or complete monoblock kits straight from Hypex:

DIYclassd.com

Quickstart Datasheet Topview

www.diyclassd.com

These units are pretty much plug-and-play and you get everything you need pretty much between the Modules and Chassis. I am working slowly on a 5-channel Monoblock construction using the NC400 and SMPS600N400 modules.

 

[lovinthehd]

What spl and at what distance are we talking about?

 

[VMPS-TIII]

Don't expect much difference in sound with any of these amps. Most quality amps are designed to be transparent. If you are looking for a fat sound that's probably a different receiver, EQ changes or a different DAC.

I have a Monolith 7x200 that seems a little more crisp than the Denon 4700 internal amps. And I have a March Audio P452 Purifi design Stereo amp that sounds a lot like the Monolith but weighs 84 pounds less.

Most likely you will do better changing your sound with EQ and a UMIK using REW software to analyze the room and then tweak it to your personal preference. If that doesn't work look at different speakers.

My Hegel H90 has a better sound than my Denon 4700 in stereo mode to my ears. But I can get the 4700 to sound a little closer with EQ changes. You might want to decide what your real goal is? More power or a fatter sound.

 

[mazersteven]

So what you're saying is the designer of the speakers designs a flat frequency response on purpose and your suggestion is the EQ them. What's the sense of having them speakers? When a speaker that's designed to give us exactly what the sound engineer has intended us to hear and you say to EQ them.

Maybe I'm absolutely totally wrong but I just have to shake my head

 

[VMPS-TIII]

So what you're saying is the designer of the speakers designs a flat frequency response on purpose and your suggestion is the EQ them. What's the sense of having them speakers? When a speaker that's designed to give us exactly what the sound engineer has intended us to hear and you say to EQ them.

Maybe I'm absolutely totally wrong but I just have to shake my head

Did you read his response? "I’ve never been thrilled with the sound out of this setup - always thought it sounded a bit “thin” if that makes sense."

I understand Jim told him to add an amp.... but my experience is an amp change doesn't suddenly make a speaker not sound thin?

Maybe your experience is different?

When I encounter a speaker that sounds thin I typically try a new house curve rather than add an amp. Rooms can change the sound significantly even for a flat speaker. UMIK and REW will tell the story.

And in some cases, I find the user's ear is looking for something different than flat FR. Everyone is different.

 

[ryanosaur]

I will agree that good electronics should not change the Sound Quality. The electronics should be free from any coloration.
I know Dennis and Jim will both discuss the importance of delivering Clean Power to the speakers. In shopping for your Amp, the most important things to consider then, are matching the impedance of the speaker to what the Amp can deliver, and that you Amp be capable of delivering enough power that you have ample Headroom to perform given the potential for Dynamic Peaks in both Music and Movie content.
If you need 1 watt to produce 88dB, then you will want about 128w of clean power to clear 105dB at your LP (a few assumptions aside).
Again, will your speakers sound different? Probably not. But knowing you have the headroom available and a good stable amp behind them is part of building a competent system.

I did not get the impression that OP is expecting a change in sound quality (ie. chocolately mids) so much as he is looking to make certain his speakers have adequate [power overall.

 

[ryanosaur]

Did you read his response? "I’ve never been thrilled with the sound out of this setup - always thought it sounded a bit “thin” if that makes sense."

I understand Jim told him to add an amp.... but my experience is an amp change doesn't suddenly make a speaker not sound thin?

Maybe your experience is different?

When I encounter a speaker that sounds thin I typically try a new house curve rather than add an amp. Rooms can change the sound significantly even for a flat speaker.

And in some cases, I find the user's ear is looking for something different than flat FR. Everyone is different.

Now this... I can get behind most of what you are saying here.

 

[highfigh]

I’m considering adding an amp to my 2 ch system, currently powering Salk Song Towers with an NAD T758. I’ve never been thrilled with the sound out of this setup - always thought it sounded a bit “thin” if that makes sense. I emailed Jim Salk and he suggested that the NAD may be a bit underpowered for the speakers and suggested adding an amp.

A local store has an open box special on a Rotel RB 1572 for $500. That’s a class D amp, but I don’t know if that should concern me or not. Couple questions:
1. Do people think adding an amp would help with the overall performance of the system?
2. Thoughts on the Rotel? I’m not looking to spend a ton of money here so open to alternatives but want to keep the budget under $1k for an amp

Move around the room and if you hear variations in the bass response, fix the actual problem, which wouldn't be the speakers if this occurs. Also, turn the balance control to either side- if the bass becomes stronger, one speaker's wiring is wrong. If you placed one speaker next to a wall and the other next to a door opening, that can really screw up the sound.

 

[mazersteven]

I agree that placement and the room would have a bigger impact I would try that before any EQ. And if I had a EQ my speakers it's time for new ones

 

[Mikado463]

not sure there is a 'wrong' answer here but 'giving up on your speakers' I would not. I agree with room analyzation for I have listened to many setups utilizing first rate components that did not live up to expectations because of poor room interaction

 

[VMPS-TIII]

I agree that placement and the room would have a bigger impact I would try that before any EQ. And if I had a EQ my speakers it's time for new ones

If you own a Denon the entire premise of the product is Audyssey. Rooms typically change the frequency response and most users can only move the speakers so much.

There is nothing wrong with EQ. In fact, Denon automatically EQ's midrange unless you go in and turn it off. lol

Most don't even know it's happening.

 

[ski2xblack]

So what you're saying is the designer of the speakers designs a flat frequency response on purpose and your suggestion is the EQ them. What's the sense of having them speakers? When a speaker that's designed to give us exactly what the sound engineer has intended us to hear and you say to EQ them.

A harsh reality: whether or not a passive speaker's respone is a perfect match for a particular location in a specific room is a roll of the dice. Consider that the highest performing rigs, from commercial JBL Synthesis systems to Doc Carter's diy system, final bsc and bass tuning is done in the actual room where the system resides. Fully active rigs.

While it's a bit of luck to get passive speakers that mesh perfectly, we do know what works, and Dennis' designs adhere to a proven formula. That doesn't ensure a perfect meshing with local acoustics in every possible room (and Dennis's designs are top notch in this regard).

So to the OP's question, it's fair to bring up eq as something to consider, as changing amps won't likely bring audible, qualitative changes. Eq is not a sin, except to cultists obsessed with marketing more than music.

 

[highfigh]

A harsh reality: whether or not a passive speaker's respone is a perfect match for a particular location in a specific room is a roll of the dice. Consider that the highest performing rigs, from commercial JBL Synthesis systems to Doc Carter's diy system, final bsc and bass tuning is done in the actual room where the system resides. Fully active rigs.

While it's a bit of luck to get passive speakers that mesh perfectly, we do know what works, and Dennis' designs adhere to a proven formula. That doesn't ensure a perfect meshing with local acoustics in every possible room (and Dennis's designs are top notch in this regard).

So to the OP's question, it's fair to bring up eq as something to consider, as changing amps won't likely bring audible, qualitative changes. Eq is not a sin, except to cultists obsessed with marketing more than music.

A position might not be the best, but that's why speakers need to be moved.

 

[ski2xblack]

A position might not be the best, but that's why speakers need to be moved.

Passive means are the cheapest!

Also effective, as in producing audible changes. The OP may be able to fix his "thin" response simply by moving the speakers a few inches closer to the wall.

 

[Swerd]

I’m considering adding an amp to my 2 ch system, currently powering Salk Song Towers with an NAD T758. I’ve never been thrilled with the sound out of this setup - always thought it sounded a bit “thin” if that makes sense. I emailed Jim Salk and he suggested that the NAD may be a bit underpowered for the speakers and suggested adding an amp.

A local store has an open box special on a Rotel RB 1572 for $500. That’s a class D amp, but I don’t know if that should concern me or not. Couple questions:
1. Do people think adding an amp would help with the overall performance of the system?
2. Thoughts on the Rotel? I’m not looking to spend a ton of money here so open to alternatives but want to keep the budget under $1k for an amp

I owned SongTowers for 9 years. I drove them with either a 70 wpc Denon AVR-1800 (bought in 2000), or with an external 200 wpc 2-channel amp, a B&K EX4420 I bought used for $400 ($1/watt), with the Denon AVR as a preamp. I owned that amp before getting the STs, but I listened to them driven both ways, just to see what difference I could notice, if any.

In my opinion, the difference was not major, but it was noticeable, and it was most noticeable in the bass. It wasn't louder or heavier sounding with more power, but it was more potent and cleaner sounding, with less 'strain' or 'effort'. Was that caused by less distortion at equivalent loudness levels? I can't say for certain. But I am confident in saying that going from 70 to 200 watts (both at 8 ohms), roughly triple the power, made a noticeable difference.

Jim Salk and Dennis Murphy both say to drive STs with 100 watts, but admit than any amp or receiver that delivers an honest 50 watts should be enough. That certainly is what I experienced. But I would add that the ST benefits from more power, can easily handle it, but doesn't require it.

I looked up the NAD T758 and was confused about it's rated power. Is it 60 or 110 watts? Two Outlaw 2220 mono amps, rated at 200 W at 8 ohms, $400 each, would be a great solution. So would the Rotel RB-1572 rated at 250 wpc at 8 ohms, but only if it is also rated at 4 ohms. I didn't see that mentioned on Rotel's RB-1572 web page.

Why did I emphasize the words triple the power? I often heard people say doubling amplifier power makes little difference in sound. If you want to make a real difference, increase power by 10-fold, a whole order of magnitude, or 1 log increase. In reality, that isn't often possible or practical. So, I chose a half a log, the square root of 10, or roughly 3-fold.

 

[William Lemmerhirt]

Passive means are the cheapest!

Also effective, as in producing audible changes. The OP may be able to fix his "thin" response simply by moving the speakers a few inches closer to the wall.

Yep absolutely. I like the term positional eq lol. Not sure where that came from but it fits. A bad room can destroy great speakers if you let it.

 

[stalag2005]

My Hegel H90 has a better sound than my Denon 4700 in stereo mode to my ears. But I can get the 4700 to sound a little closer with EQ changes. You might want to decide what your real goal is? More power or a fatter sound.

I did not know that sound needed to be fat. Does it need donations? I can undergo lipo if you need 20 or so pounds now!........

 

[tmurnin]

Thanks for the response(s)! Trying to answer a bunch of questions here:

the T758 is 60w, so the Rotel would increase power quite a bit.

the room is a finished basement area with hard surface floors (vinyl plank laminate) with an area rug between the speakers and the listing position (roughly 10’ away). I have hung some acoustic wall treatments on the wall opposite the speakers (roughly 2’ away) but the rest of the walls are pretty hard surface, so that isn’t ideal but it is what it is.

I’m not interested in giving up on the speakers. These are well reviewed and well thought of speakers by almost everyone who has experienced Salk, so I believe the issue is in my setup. I also have a Hsu subwoofer connected for some of the lower end bass.

EQ - I did run Dirac on the NAD a couple months after I got everything set up. That improved things a bit and perhaps compensated for some of the room issues but still not exactly what I want.

room size - roughly 18 x 30 x 7.5. System is set up on one of the shorter walls.

I will try moving the towers closer to the wall and see if that helps anything