Power Hungry SDA 2B's ???

Summerwind2

So I connected my SDAs to my Pioneer Elite VSX 05 switched to 6ohm.
Its a solid 100wpc into 8ohms but man I had to crank it up to 50% volume for the SDAs to wake-up but still was lacking mid bass.
I've placed them 10' apart and 6" from the wall and I found the sweet spot dead center @ 8 to 9' from the SDAs.
I'm thinking I need more power to get that mid bass punch.
Thoughts?

Nightfall

I believe they're like the RTA-12's in that they can take 500 watts? Everyone recommends a lot of power to get them to wake up.

Mystery

I have studio 2B's and if I go near 1/2 on my Pioneer Elite VSX-07TX Receiver, I have to put palms over my ears.
May be your input level is too low or the room is huge.

Nightfall

Mystery wrote: »

I have studio 2B's and if I go near 1/2 on my Pioneer Elite VSX-07TX Receiver, I have to put palms over my ears.
May be your input level is too low or the room is huge.

I thought I remember a Marantz?

bigaltx24

Make sure they're not hooked up out of phase. If they are in phase you might want to consider a higher power amp.

polrbehr

I think something is amiss here. I run my 2Bs with an Adcom GFA535 @ 60wpc, and at -10 you can feel every note.

It almost sounds like the SDA cable isn't hooked up (I know that's not likely, but it's worth checking IMO)

TennMan

I have an Adcom gfa-555 (200wpc) but the Adcom gfa-545 (100wpc) use to have powered my 2Bs without problems. When comparing them I never had to set the volume higher for the lower powered amp. With either amp the sound was/is best with the volume set on my preamp at about 35-40%. 50% will run you out of the room (14'x20'). With 100 watts you should have plenty of power unless you still have a disco ball hanging from your ceiling. lol I would check all the connections to be sure the polarity is correct. Having the polarity wrong can have a big effect on the bass and the SDA effect of the 2Bs.

Summerwind2

It's a large room. 16' wide and 24' long with a vaulted ceiling on thick rugs
I'm sure it's in phase but will check again and report back.
It's loud, clean, great staging but it's lacking depth.
And the ball stays :cool:

Nightfall

MCACC didn't do anything weird did it? Like set a real high crossover point?

Summerwind2

Nightfall wrote: »

MCACC didn't do anything weird did it? Like set a real high crossover point?

ll

All settings are flat. I can play with the crossover via GUI.

gudnoyez

I also have run my 2B's off my Adcom gfa-545II and my gfa-555II and agree both do I fine job, at 50% on either one would run you out of the room and piss the neighbors off, all while sounding fantastic.

zingo

I know with the 400wpc that I feed my SDAs, they sound fine but flat with the volume at 9 o'clock. Once I get passed there, the sound stage gets much deeper and full, the music is more dynamic and punchy, and overall has more weight.

Nightfall

Is it appropriate to compare a dedicated amp to an AVR? I'm in no way saying you guys are wrong, don't take it the wrong way. I've heard nothing but good things about Pioneers D Class AVR's and it's on my list to replace my Yamaha but I'm still curious if it's a fair comparison, as good as they are.

Summerwind2

Nightfall wrote: »

Is it appropriate to compare a dedicated amp to an AVR? I'm in no way saying you guys are wrong, don't take it the wrong way. I've heard nothing but good things about Pioneers D Class AVR's and it's on my list to replace my Yamaha but I'm still curious if it's a fair comparison, as good as they are.

I think its fair in 2 channel mode with no effects. (DSP) AVR is only powering the SDA

Nightfall

Also, don't quote me, but I remember reading something saying the ICE amps don't handle low impedance as well as the newer SC's.

zingo

ICEpower amps are usually pretty good at low impedance/heavy loads, which is why they are often used for subwoofer duty.

F1nut

Switch back to 8 ohms as all you're doing with the 6 ohm setting is limiting current.

Thick carpet means you must spike the speakers otherwise you'll never get any kind of bass punch.

Are they on the short or long wall? How far from the side walls? 10 feet apart is pretty far, try 6 to 8 feet.

Nightfall

I'm not sharing this as fact, just passing it along. Could be BS?

Audioholics member wrote:

This receiver uses class D ICE (Intelligent Compact Efficient) amps.

This highly efficient, almost 100%, topology of class D amps was developed by Karsten Nielsen for his PhD thesis he defended in 1999. This technology has been developed by B & O who bought out Nielsen's share in July of this year.

B & O have licensed this technology to among others, Samsung for mobile phones and Sanyo for the development of dual channel output MOSFET switching amp chips, which appeared in 2004.

B & O have produced high end amps for among others ROTEL and Jeff Rowland.

The Sanyo chip has been embraced by the car audio amp manufacturers. Obviously amp efficiency is a big concern to them.

Now one of the problems with class D amps has been a very narrow optimal impedance range over which they work optimally. So the use of this technology has been very attractive for speakers with active crossovers and the amp connected to the drive units directly. In this way the impedance is a known quantity. Car audio manufacturers and enthusiasts have for a long time embraced active crossovers and bi and triamping.

Now we have long suspected that the next wave of A/V receivers would embrace this technology and the Sanyo chips in particular. These produce virtually no heat, are very cheap, small and minimize power requirements and ancillary circuit components.

I think I would be correct to assume that this Pioneer receiver uses the Sanyo dual MOSFET chips.

Now this post has caused me to study the details of these dual channel chips.

The following chips are available, 100 watts X 2, 150 watts X 2 and 200 watts X2

I assume that this receiver uses the 150 watt per channel chips.

Now these chips are 4 ohm rated, however there is a snag.

The line voltage of these chips is 33 volts. This gives 150 watts per channel into 8 ohms. The power into 6 ohms is 180 watts, and the power into four ohms is 150 watts, but THD rises to a whopping 10%

Now the THD into 8 ohms at 130 watts is an excellent 0.05%. At 140 watts it is 0.09%

At 180 watts into 6 ohms, the THD is 1%

Pioneer do not state THD figures below 6 ohms. However the Sanyo spec sheet quotes 10% THD at full power, 150 watts into four ohms. I can not find a power curve, but I suspect that at lower powers distortion drops.

http://forums.audioholics.com/forums/amps-pre-pros-receivers/47503-pioneer-sc-07-4-ohm-speakers.html

deronb1

Check for air leaks. A properly sealed cabinet will not have to be cranked to achieve good midbass depth on 2Bs. They are efficient 90db.

Summerwind2

F1nut wrote: »

Switch back to 8 ohms as all you're doing with the 6 ohm setting is limiting current.

Thick carpet means you must spike the speakers otherwise you'll never get any kind of bass punch.

Are they on the short or long wall? How far from the side walls? 10 feet apart is pretty far, try 6 to 8 feet.

I too was thinking about switching back to 8ohms and carpet spikes
They're on the short wall and 3' off the side walls.

Summerwind2

Nightfall wrote: »

I'm not sharing this as fact, just passing it along. Could be BS?



http://forums.audioholics.com/forums/amps-pre-pros-receivers/47503-pioneer-sc-07-4-ohm-speakers.html

Nightfall, great short meaningful read, thanks for doing the leg-work.

Easy Runnin

If your interested, I could stop by tonight with my NAD 2400.

Summerwind2

Easy Runnin wrote: »

If your interested, I could stop by tonight with my NAD 2400.

Hey thanks for the offer. I may take you up on this. I'm going to connect my Advent 1's to use as a control variable. I want to ensure all SDA connections are proper and the speaker are sealed.

Summerwind2

Easy Runnin wrote: »

If your interested, I could stop by tonight with my NAD 2400.

Hey thanks for the offer. I may take you up on this. I'm going to connect my Advent 1's to use as a control variable. I want to ensure all SDA connections are proper and the speaker are sealed.

smglbrth

F1nut wrote: »

Switch back to 8 ohms as all you're doing with the 6 ohm setting is limiting current.

Thick carpet means you must spike the speakers otherwise you'll never get any kind of bass punch.

Are they on the short or long wall? How far from the side walls? 10 feet apart is pretty far, try 6 to 8 feet.

This^^^ When I had my 2A's a little over 8ft apart it sounded a little "hollow". When I put them back to 7ft apart the warmth and fullness came back. For me, it didn't matter how many feet they were from the side walls (over 3ft that is, they are more than 7ft now). For reference mine are also about a foot away from the back wall...

Mystery

Marantz is for H/T (Deftech BP10, B&W 110i, MA 301) and the Pioneer is for music (2B, CRS+ and Boston A400). :cool:

When I play movies in blu-ray, the output level is so low that I have to increase volume by like 4 times more than from my computer.
DVD players are not that bad.
For example, my normal level is around 33 on the Marantz playing via computer.
DVD is around 25 and blu-ray I have to increase it to 15.
Less number volume is higher in this receiver.
If I play song at 15 from laptop, it'll bleed my ears.

Summerwind2

Question; Do input sources have any impact on sound quality? CD vs Tape vs DVD?

zingo

Nightfall wrote: »

Is it appropriate to compare a dedicated amp to an AVR?

Why not? He's asking about performance and if that correlates to power. As posted by a few other, there may be issues of spiking, placement, cabinet seal, but if someone has a more powerful amplifier and doesn't have mid-bass issues, wouldn't if be helpful for him to know that?

Nightfall wrote: »

I'm not sharing this as fact, just passing it along. Could be BS?

Not BS, and thanks for the read, but the specific implementation of ICEpower modules in Pioneer gear is very different than in other designs. I know that Wyred4Sound does not have any problems with low-impedance loads on their amps, but they have purpose built a customized the ICEpower modules with a matching power supply. Even an ICEpower amp that I built for my father-in-law with a stock pair of ASP modules to power his LSi15s have never had a problem or run out of steam. I like the Pioneer class-D receivers, but like any receiver, they have to make design sacrifices.

Polkie2009

Summerwind2 wrote: »

Question; Do input sources have any impact on sound quality? CD vs Tape vs DVD?

I know on my Yamaha 663, I can adjust each input sources db's + and -, are you having the same problem when you listen to a cd or tuner, mp3, or other dvd player etc.? +1 on Easy Runnin's offer to try the NAD , see how she runs with it.

BlueFox

Summerwind2 wrote: »

Question; Do input sources have any impact on sound quality? CD vs Tape vs DVD?

Of course they do. Nothing personal, but if you are asking that then you have a lot of learning to do. As others say, "Get your read on", and start researching.

And, cables (power, speaker, interconnects) also have a huge impact on sound quality, so it isn't only the source that matters.

Summerwind2

BlueFox wrote: »

Of course they do. Nothing personal, but if you are asking that then you have a lot of learning to do. As others say, "Get your read on", and start researching.

And, cables (power, speaker, interconnects) also have a huge impact on sound quality, so it isn't only the source that matters.

Blue Fox, I would like to think we all have much to learn, so maybe you can help by shedding some light on this issue for me if you don't mind.
What would one significant difference if I used a CD input source over a tape input source? Thanks!