This amp a good match for my speakers? - AVS | Home Theater Discussions And Reviews
Forum Jump: 
 
Thread Tools
post #1 of 10 Old 01-28-2012, 12:10 AM - Thread Starter
Newbie
 
XxiPiratexX's Avatar
 
Join Date: Jan 2012
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Hey Guys! Name's Brandon... LONG time reader, FIRST time poster.
<3 this website btw


I currently have a pretty random stereo system pieced together right now. Marantz Model 1515 hooked up to a pair of JBL Northridge 310's, and a Yamaha surround reciever I use as a pre-amp for my Cerwin Vega LW-15 subwoofer.

The Marantz is WAY under-powered for my JBL towers (rated 15wpc but it HAS to be higher than that), but will still make the mids pop for some reason ( clipping probably? ) Max recommended power for the towers is 250w apiece so they are not being pushed to hard at all. I was wanting to look into a receiver with less total harmonic distortion because I have read these towers need very clean power and almost no total harmonic distortion to not clip.

I have a possible chance to pick up a Rotel RB-985 for probably under $100, maybe under $50... then I would look for the matching pre-amp on ebay. I have read good reviews about the reciever and it seems to be a solid made amp with clean power. Would this amp be a good choice for my towers?

Any input would be awesome as I really respect your guy's knowledge on the subject.
XxiPiratexX is offline  
Sponsored Links
Advertisement
 
post #2 of 10 Old 01-28-2012, 07:13 AM - Thread Starter
Newbie
 
XxiPiratexX's Avatar
 
Join Date: Jan 2012
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
bump
XxiPiratexX is offline  
post #3 of 10 Old 01-28-2012, 07:49 AM
AVS Special Member
 
commsysman's Avatar
 
Join Date: Dec 2007
Location: Southern California
Posts: 5,372
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 178 Post(s)
Liked: 267
If your speakers are rated to handle 250W, you probably should have an amplifier or receiver that is rated for 60W to 150W to drive them.

Your 15 watt amplifier is no doubt clipping if you try to play it loud at all.

The RB-985 would be a great amplifier to have, but the price seems way to good to be true; I would expect it to sell for $500-800 used. Are you sure it isn't broken?


Quote:
Originally Posted by XxiPiratexX View Post

Hey Guys! Name's Brandon... LONG time reader, FIRST time poster.
<3 this website btw


I currently have a pretty random stereo system pieced together right now. Marantz Model 1515 hooked up to a pair of JBL Northridge 310's, and a Yamaha surround reciever I use as a pre-amp for my Cerwin Vega LW-15 subwoofer.

The Marantz is WAY under-powered for my JBL towers (rated 15wpc but it HAS to be higher than that), but will still make the mids pop for some reason ( clipping probably? ) Max recommended power for the towers is 250w apiece so they are not being pushed to hard at all. I was wanting to look into a receiver with less total harmonic distortion because I have read these towers need very clean power and almost no total harmonic distortion to not clip.

I have a possible chance to pick up a Rotel RB-985 for probably under $100, maybe under $50... then I would look for the matching pre-amp on ebay. I have read good reviews about the reciever and it seems to be a solid made amp with clean power. Would this amp be a good choice for my towers?

Any input would be awesome as I really respect your guy's knowledge on the subject.

commsysman is online now  
post #4 of 10 Old 01-28-2012, 07:53 AM
AVS Special Member
 
eljaycanuck's Avatar
 
Join Date: Oct 2007
Location: Ottawa, Canada
Posts: 5,642
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 232 Post(s)
Liked: 612
According to specs I was able to find on-line, the JBLs are fairly sensitive (91dB) 8Ω speakers. Max amp power is 250, but there's no indication of what min amp power should be.

I agree that your Marantz - which is rated at 15W/ch. @ 8Ω and 17W/ch @ 4Ω - is insufficiently powerful to drive the speakers properly. The Rotel you're eyeing - which is rated at 100W/ch @ 8Ω - would be a very good replacement.

If the level of the 1515's tape output is variable - and I can't find any information on-line to indicate whether or not it is - you could use the the 1515 as a pre-amp until such time as you find a proper replacement.
eljaycanuck is offline  
post #5 of 10 Old 01-28-2012, 08:00 AM
AVS Special Member
 
YeuEmMaiMai's Avatar
 
Join Date: Apr 2002
Posts: 1,076
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
I had an old sony mini bookself system that was 18wpc and it had no problems driving a pair of NS-6490's that were rated 10w min 140w max (original NS-6490's not the newer ones) to the point where it was reasonably loud without distorting... it takes the most power to drive the woofer in the speakers not the mid and tweet.

Strong or weak in the end we are all dead
YeuEmMaiMai is offline  
post #6 of 10 Old 01-28-2012, 08:37 AM - Thread Starter
Newbie
 
XxiPiratexX's Avatar
 
Join Date: Jan 2012
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by commsysman View Post

If your speakers are rated to handle 250W, you probably should have an amplifier or receiver that is rated for 60W to 150W to drive them.

Your 15 watt amplifier is no doubt clipping if you try to play it loud at all.

The RB-985 would be a great amplifier to have, but the price seems way to good to be true; I would expect it to sell for $500-800 used. Are you sure it isn't broken?

It's at a second hand electronics store and they don't know what the stereo stuff is really worth... They have lots of Rotel, Marantz, Denon, Adcom, Nakimichi... All high end, vintage stuff that has been donated.

It's insane people donate this high quality equipment. Must be rich folk I guess lol
XxiPiratexX is offline  
post #7 of 10 Old 01-28-2012, 10:22 AM - Thread Starter
Newbie
 
XxiPiratexX's Avatar
 
Join Date: Jan 2012
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
So, you think that this Rotel RB-985 will be all the power I would ever need for these JBL ND310's?

I have one more question. I know very little about pre-amps and was wondering how important is quality in a pre-amp? Does it have a lot of effect of the final sound produced by the actual power receiver OR is it simply volume control?

Also, I use a Technics 8 band equalizer and have most of the treble at +6 threw +9 DB. This is safe, correct? Can equalizers cause clipping to happen before it would without one?
XxiPiratexX is offline  
post #8 of 10 Old 01-28-2012, 12:36 PM - Thread Starter
Newbie
 
XxiPiratexX's Avatar
 
Join Date: Jan 2012
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
^^^
XxiPiratexX is offline  
post #9 of 10 Old 01-28-2012, 12:48 PM
AVS Special Member
 
Secret Squirrel's Avatar
 
Join Date: Mar 2009
Location: Midwest U.S.A.
Posts: 2,264
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Liked: 19
There is really no need to go expensive on a pre amp. Especially when they all basically do the same thing. An AVR with a pre amp section will do the same job as a dedicated pre amp. The AVR will be cheaper. You might be able to get a deal on a used AVR with a pre amp built in. Boosting frequencies with an EQ can cause clipping to happen sooner. Especially with a 15 watt amplifier. In my opinion you're boosting a little to much.
Secret Squirrel is offline  
post #10 of 10 Old 01-28-2012, 04:27 PM - Thread Starter
Newbie
 
XxiPiratexX's Avatar
 
Join Date: Jan 2012
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Cool, Thank's Squirrel! Ill turn down the EQ
XxiPiratexX is offline  
Sponsored Links
Advertisement
 
Reply Speakers

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