4 ohm: External Amp or Marantz 5009 - AVS Forum
Forum Jump: 
 1Likes
  • 1 Post By arnyk
 
Thread Tools
post #1 of 22 Old 08-22-2014, 07:18 AM - Thread Starter
Newbie
 
swampjelly's Avatar
 
Join Date: Jan 2013
Posts: 14
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
4 ohm: External Amp or Marantz 5009

I got on AVS this morning to ask for amp suggestions to drive my soon-to-be purchased Monitor Audio Silver 8's. I just purchased a Marantz 5008 after moving my 5007 to our bedroom.

Then I saw a thread about the 5009 adding 4 ohm output! It would be a lot simpler and easier to have a 4 ohm receiver. One less thing to plug into the wall, less cords, less heat.

SO shouldn't I just return my unopened 5008 & pick up a 5009 instead?
swampjelly is offline  
Sponsored Links
Advertisement
 
post #2 of 22 Old 08-22-2014, 07:45 AM
585-645-1006
 
jdsmoothie's Avatar
 
Join Date: Sep 2007
Location: Orlando, FL
Posts: 44,408
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 986 Post(s)
Liked: 1495
The 5009 simply adds a current limiting setting (p. 28 Owner's manual) which will cap the AVR at a lower maximum volume level than would be the case with the 5008. No difference in power specs between the two models. If you want to go to louder than moderate volume levels, external amplification would be required with either model.

---------------------------------
"JD" –
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
; shop.avscience.com ; 585-645-1006, AVScience - Authorized dealer for AV Gear 

Mon - Fri: 8am – 8pm EST (Sat/Sun too, will return call if I don't pick up)
Call for pricing on Denon, Marantz, Yamaha, Def Tech, Atlantic Tech, Parasound
** Think the AVR is defective?  Reset the microprocessor 4-5 times. 

Last edited by jdsmoothie; 08-22-2014 at 07:49 AM.
jdsmoothie is offline  
post #3 of 22 Old 08-22-2014, 07:59 AM - Thread Starter
Newbie
 
swampjelly's Avatar
 
Join Date: Jan 2013
Posts: 14
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
SO I should probably just try it without an external amp, knowing that the 5009 will shut off if I play it too loud?

Would I be able to tell much of a difference in the sound with an external amp?
swampjelly is offline  
post #4 of 22 Old 08-22-2014, 08:19 AM
585-645-1006
 
jdsmoothie's Avatar
 
Join Date: Sep 2007
Location: Orlando, FL
Posts: 44,408
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 986 Post(s)
Liked: 1495
Yes to the first and likely no to the second, rather it would allow the AVR to go to higher volume levels if using a more powerful amp (eg. Emotiva XPA-2).

---------------------------------
"JD" –
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
; shop.avscience.com ; 585-645-1006, AVScience - Authorized dealer for AV Gear 

Mon - Fri: 8am – 8pm EST (Sat/Sun too, will return call if I don't pick up)
Call for pricing on Denon, Marantz, Yamaha, Def Tech, Atlantic Tech, Parasound
** Think the AVR is defective?  Reset the microprocessor 4-5 times. 
jdsmoothie is offline  
post #5 of 22 Old 08-22-2014, 08:36 AM - Thread Starter
Newbie
 
swampjelly's Avatar
 
Join Date: Jan 2013
Posts: 14
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
MANY THANKS for your help!
swampjelly is offline  
post #6 of 22 Old 08-22-2014, 11:26 AM
AVS Special Member
 
fatbottom's Avatar
 
Join Date: May 2003
Location: UK
Posts: 3,771
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 404 Post(s)
Liked: 185
In my experience using 4 ohm speakers with AVR's sounds bad.

Krell Evolution 900e x 7

Bose Jewel speakers.

 

Jealous of my speakers?

fatbottom is online now  
post #7 of 22 Old 08-22-2014, 12:00 PM
AVS Special Member
 
DonH50's Avatar
 
Join Date: Feb 2010
Location: Monument CO
Posts: 6,087
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 159 Post(s)
Liked: 262
The 5008 is rated at 140 W into 6 ohms. Assuming it does that into 4 ohms (probably do a bit more), then 140 W into your 90 dB/W/m Monitor 8's will produce ~103 dB for the pair at 12 feet away. IOW, +1 to jdsmoothie. A 300 W amp would only slightly increase the max output (3 dB increase is not a very big increase in volume) and would exceed the power ratings of your speakers. I'd stick with the Marantz 5008 until proven otherwise.

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
DonH50 is offline  
post #8 of 22 Old 08-22-2014, 02:04 PM
AVS Special Member
 
fatbottom's Avatar
 
Join Date: May 2003
Location: UK
Posts: 3,771
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 404 Post(s)
Liked: 185
Quote:
Originally Posted by DonH50 View Post
The 5008 is rated at 140 W into 6 ohms. Assuming it does that into 4 ohms (probably do a bit more), then 140 W into your 90 dB/W/m Monitor 8's will produce ~103 dB for the pair at 12 feet away. IOW, +1 to jdsmoothie. A 300 W amp would only slightly increase the max output (3 dB increase is not a very big increase in volume) and would exceed the power ratings of your speakers. I'd stick with the Marantz 5008 until proven otherwise.
There is simply more to it than power IMO. It's not the power it's the ability of the amp to drive 4ohm (or lower) speakers.

A 60W amp handled 4ohm speakers much better than a 70W amp (I know 10W isn't anything) However according to you, they should be the same. They weren't. The 60W amp had a much higher capacity power supply.

Krell Evolution 900e x 7

Bose Jewel speakers.

 

Jealous of my speakers?

fatbottom is online now  
post #9 of 22 Old 08-22-2014, 03:03 PM
AVS Special Member
 
DonH50's Avatar
 
Join Date: Feb 2010
Location: Monument CO
Posts: 6,087
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 159 Post(s)
Liked: 262
My post was to the OP not in response to your post. I think everyone knows your position. I did not say anything about all amplifiers being the same; that is not my position and you are reading too much into my response. I do have some knowledge of amplifier circuits and how various parameters relate in the design. I was not trying to debate your position; pretend there were other posts between ours and move on.

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
DonH50 is offline  
post #10 of 22 Old 08-23-2014, 07:25 AM
Senior Member
 
audio4life's Avatar
 
Join Date: Sep 2013
Posts: 422
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 11 Post(s)
Liked: 140
Quote:
Originally Posted by DonH50 View Post
The 5008 is rated at 140 W into 6 ohms. Assuming it does that into 4 ohms (probably do a bit more), then 140 W into your 90 dB/W/m Monitor 8's will produce ~103 dB for the pair at 12 feet away. IOW, +1 to jdsmoothie. A 300 W amp would only slightly increase the max output (3 dB increase is not a very big increase in volume) and would exceed the power ratings of your speakers. I'd stick with the Marantz 5008 until proven otherwise.
You should be aware that the power specs you are quoting is with 2 channels driven. A very different picture emerges when more than 2 channels are driven at once. The max power draw spec on the back of the unit bears this up. And it is telling that Marantz does not give a 4 ohm spec. You may suggest staying with the Marantz, but as of yet you have no idea the room measurements involved or the volume levels desired by the owner.
audio4life is offline  
post #11 of 22 Old 08-23-2014, 10:24 AM
AVS Special Member
 
DonH50's Avatar
 
Join Date: Feb 2010
Location: Monument CO
Posts: 6,087
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 159 Post(s)
Liked: 262
True, although IMO the need for full power on every channel is over rated. As for room and volume level (SPL), nor do you (I assume), and that is why I cited a specific example giving power, distance, and resulting SPL. The SPL calculator I used is at http://myhometheater.homestead.com/splcalculator.html and I assumed two speakers with no room gain ("away from walls").

For the same scenario, 100 dB is reached with 60 W, 90 dB with 6 W, and 80 dB with only 0.6 W. 80 dB average is usually too loud for me but you do need headroom for long peaks. I suspect 100 W is plenty enough the vast majority of the time, and if a gunshot or explosion (or even loud snare hit) gets clipped it's unlikely anybody would notice.

One other thing worth mentioning is that I have no idea the actual impedance curve of the Monitor 80's. If it has very low dips at low frequencies the Marantz could have problems if the listener is fairly far away and likes it loud. No way for me to tell, but my default answer is to try the AVR first before jumping on the amplifier bandwagon. There are usually lots of other things to spend money on.

IMO, IME, YMMV, my 0.000001 cents (microcent), etc. - Don

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
DonH50 is offline  
post #12 of 22 Old 08-23-2014, 12:19 PM
Senior Member
 
audio4life's Avatar
 
Join Date: Sep 2013
Posts: 422
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 11 Post(s)
Liked: 140
I'm not arguing on the need for all-channels-driven-power. What I said was, when more than 2 channels are driven a different picture emerges. I am not interested in getting into a debate on amps vs AVRs. I am simply saying one can not really make a suggestion that is helpful without getting some more details on the room and seating distance, for instance, and what volume levels the person is hoping to achieve at his seating area.
audio4life is offline  
post #13 of 22 Old 08-23-2014, 01:54 PM
AVS Special Member
 
DonH50's Avatar
 
Join Date: Feb 2010
Location: Monument CO
Posts: 6,087
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 159 Post(s)
Liked: 262
Then I suppose a better response than arguing the merits (or lack of) in my post and concluding it is unhelpful would be to address the OP:

swampjelly: How far away are you from your speakers, and how loud do you normally play them?

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
DonH50 is offline  
post #14 of 22 Old 08-23-2014, 02:06 PM
FMW
AVS Special Member
 
FMW's Avatar
 
Join Date: Jun 2007
Posts: 4,849
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 266 Post(s)
Liked: 710
Quote:
Originally Posted by fatbottom View Post
In my experience using 4 ohm speakers with AVR's sounds bad.
Only if played too loud. It is all about volume level.
FMW is offline  
post #15 of 22 Old 08-23-2014, 02:07 PM
FMW
AVS Special Member
 
FMW's Avatar
 
Join Date: Jun 2007
Posts: 4,849
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 266 Post(s)
Liked: 710
Quote:
Originally Posted by fatbottom View Post
There is simply more to it than power IMO. It's not the power it's the ability of the amp to drive 4ohm (or lower) speakers.

A 60W amp handled 4ohm speakers much better than a 70W amp (I know 10W isn't anything) However according to you, they should be the same. They weren't. The 60W amp had a much higher capacity power supply.
Any amp can drive 4 ohm speakers. It is just a matter of power dissipation. So actually, it is all about power.
FMW is offline  
post #16 of 22 Old 08-23-2014, 03:58 PM
Member
 
ohrbrcko's Avatar
 
Join Date: Oct 2003
Posts: 165
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Liked: 20
I have the MA Silver 10s powered by a Parasound A-21. Really a great combination. My AVR is a Yamaha RX-V1030. Parasound is worth a look. Does not get very warm at all.
ohrbrcko is offline  
post #17 of 22 Old 08-24-2014, 04:17 AM
Member
 
TomC1315's Avatar
 
Join Date: Oct 2013
Location: Lakewood, Ohio
Posts: 197
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Liked: 57
FWIW ... I've owned a Marantz SR5007 for the past 20 months, paired up with three 4ohm speakers (MartinLogan Motion 40s and a Motion 30 center) and a pair of 5 ohm surrounds (ML LX16s).

During the winter months, things seem fine (thermostat set around 64 degrees).

During the summer, however, the AVR can get pretty hot to the touch (we don't run the AC until temps reach the upper 80s) ... to manage the AVR's internal temp, I've run a small Cool Components dual fan at about 1/2 to 2/3 speed (full speed is too loud), and this helps keep the AVR from becoming too hot. If I'm in the adjacent dining/computer room (on a really warm day) I'll even point a floor fan towards the unit and this will keep things very well in check.

Additionally, I've designed a shelf that I can pull the AVR out about 4" from the armoire in which it is placed ... and finally, there is almost 3'' of space above the SR5007 ... all for as much breathing room as I can manage.

Nevertheless, I've become tired of trying to manage this situation - and worry that, because of the "hot to the touch" temp that result sometimes without the (noisy) fans involved, that I may be overworking the SR5007, resulting in a shorter life span for the unit.

Therefore, I decided to add an amplifier. I was all set to order an Emotiva UPA 500 (120watts per channel @ 4ohms) for $349 and provide my hard working Marantz AVR some (IMO) much needed and capable assistance.
I was really hoping that Emotiva had an offering somewhere between the (120wpc @ 4ohms) UPA 500 and the (330wpc @ 4ohm) XPA-3 / (300wpc @ 4ohm) XPA-5 ... something in the 200wpc range ... but they don't.
When I asked about b-stock inventory at Emotiva, I was told that the UPAs are already marked down as far as they can go, and that the XPA-3 was selling for $650 and the XPA-5 was at $800.
I ordered the XPA-3 and will use the Marantz to drive the surrounds.

I haven't received my RCA cables yet ... I'm looking forward to hearing how an amp will "open up" the sound coming from the ML Motion speakers ... and I expect that the AVR will be able to drive the surrounds without much difficulting, and therefore retire my Cool Components unit.

Click image for larger version

Name:	IMG_0793.jpg
Views:	10
Size:	230.3 KB
ID:	226762

MartinLogan Motion 40s / 30 / LX16s
Marantz SR5007 / UD5007
Emotiva XPA-3
SVS PC13ultra

exercise room: MartinLogan LX16s / Dynamo700

Last edited by TomC1315; 08-24-2014 at 04:34 AM.
TomC1315 is online now  
post #18 of 22 Old 08-24-2014, 04:27 AM
AVS Special Member
 
fatbottom's Avatar
 
Join Date: May 2003
Location: UK
Posts: 3,771
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 404 Post(s)
Liked: 185
Can't see how you can complain about $650 for the Emotiva. If I convert the ATI 2003 back into $, it's $3200

Quote:
I haven't received my RCA cables yet ... I'm looking forward to hearing how an amp will "open up" the sound coming from the ML Motion speakers
Hearing bias. Will sound exactly the same

;-)

Krell Evolution 900e x 7

Bose Jewel speakers.

 

Jealous of my speakers?

fatbottom is online now  
post #19 of 22 Old 08-24-2014, 04:38 AM
Member
 
TomC1315's Avatar
 
Join Date: Oct 2013
Location: Lakewood, Ohio
Posts: 197
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Liked: 57
Thumbs up

I wasn't complaining :-)

I'm delighted that I could get my hands on this unit for that price.

MartinLogan Motion 40s / 30 / LX16s
Marantz SR5007 / UD5007
Emotiva XPA-3
SVS PC13ultra

exercise room: MartinLogan LX16s / Dynamo700
TomC1315 is online now  
post #20 of 22 Old 08-24-2014, 06:17 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,381
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 747 Post(s)
Liked: 1161
Quote:
Originally Posted by fatbottom View Post
There is simply more to it than power IMO. It's not the power it's the ability of the amp to drive 4ohm (or lower) speakers.
That is all very true. However AVRs as a rule do very well driving low impedance speakers with music. Usually their first mode of difficulty occurs if they shut down while playing very loudly. This affects very few people and can be avoided by improving ventilation, sometimes with extra cooling fans that can be very quiet, easy to set up, and cost very little.

Quote:
A 60W amp handled 4ohm speakers much better than a 70W amp (I know 10W isn't anything) However according to you, they should be the same. They weren't. The 60W amp had a much higher capacity power supply.
It is not about more or better, its all about adequate or inadequate. No doubt a 2 KW amp will deliver more power to a speaker than a 120 watt amp. However, that 2 KW amp if fully exploited will damage most speakers used for home audio. So more is not an advantage at all unless there is actually manifest purpose for it.
arnyk is offline  
post #21 of 22 Old 08-24-2014, 06:33 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,381
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 747 Post(s)
Liked: 1161
Quote:
Originally Posted by TomC1315 View Post
FWIW ... I've owned a Marantz SR5007 for the past 20 months, paired up with three 4ohm speakers (MartinLogan Motion 40s and a Motion 30 center) and a pair of 5 ohm surrounds (ML LX16s).

During the winter months, things seem fine (thermostat set around 64 degrees).

During the summer, however, the AVR can get pretty hot to the touch (we don't run the AC until temps reach the upper 80s) ... to manage the AVR's internal temp, I've run a small Cool Components dual fan at about 1/2 to 2/3 speed (full speed is too loud), and this helps keep the AVR from becoming too hot.

The Cool Components Dual Fan unit looks like a slick package, but I'm sorry to hear that it can be too noisy.

There are more effective approaches that are far quieter and move more air.

For example I pulled a couple of 120 mm quiet fans from stock, and powered them with a 12 volt wall wart.

These fans have a built in speed switch but are about 10 dB quieter in their high speed mode and a whopping 20 dB quieter in their low speed.

http://www.ebay.com/itm/Brand-New-An...-/320883392760



The 12 volt power supply I use is this one:

http://www.ebay.com/itm/HOT-12V-2A-P...-/261569926092



The wring is low voltage and can be spliced very neatly and safely connected with these:



which you can also get on the web or at home improvement stores (they are general purpose but designed for telephone and alarm wiring).

The fans have rubber mountings that will keep them steady and shake free when you sit them on top of your AVR's top cooling vents. You can also use them to exhaust hot air from an equipment cabinet.

Here is a temperature controller that you can use to shut them off when not needed:

http://www.ebay.com/itm/50-110-C-DC1...-/400677190587

TomC1315 likes this.
arnyk is offline  
post #22 of 22 Old 08-24-2014, 09:47 AM
Senior Member
 
audio4life's Avatar
 
Join Date: Sep 2013
Posts: 422
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 11 Post(s)
Liked: 140
Quote:
Originally Posted by FMW View Post
Only if played too loud. It is all about volume level.
And as Tomc has so clearly illustrated, heat, volume and stress on the component are all part of the equation.
audio4life is offline  
Reply Receivers, Amps, and Processors

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off