RF-7II 's And Krell S-300i Integrated

[JefDC]

I have experienced a similar situation (lack of bass) with my RP-8060FA speakers.

 

They where powered by a Denon AVR4300 amplifier, this amplifier is rated 130 Watt @ 8 Ohm and 190 Watt @ 4 Ohm. At first glance these figures appear more than enough, but as the older speaker model (RP-280FA) had an impedance which dipped below 3 Ohm I suspect the RP-8060's are similar and it seems the Denon cannot supply enough current at these low impedances.

 

I connected a class D amplifier (XTZ Edge A2-300 based on an ICEpower 300AS1 module) this amplifier has a comparable power rating of 150Watt @ 8 Ohm's but can generate a lot of current (as indicated by a rating of 300 Watt @ 4 Ohm en 460 Watt @ 2.7 Ohm).

The difference is very evident - with the external amp the doors rattle in their frames with the Denon not.

 

 

 

 

[Codyred]

JefDC, the effect of a high current amp is overlooked frequently and sometimes dismissed by folks that post in audio forums. I saw in one thread where a guy stated that the idea of "high current" was audiophile pig slop, or something like that.  When speaker impedance dips below 4 ohms in the bass region, I firmly believe that's something to consider.

[Zen Traveler]

58 minutes ago, Codyred said:

JefDC, the effect of a high current amp is overlooked frequently and sometimes dismissed by folks that post in audio forums. I saw in one thread where a guy stated that the idea of "high current" was audiophile pig slop, or something like that. 

You can find pretty much anything on the internet including folks telling you that you need an external amp to get the most out of your speakers, while others seem perfectly happy not using one.

58 minutes ago, Codyred said:

 

When speaker impedance dips below 4 ohms in the bass region, I firmly believe that's something to consider.

Sure. If you are worried about it purchase either an AVR or Power Amp that is rated to drive 4 Ohm speakers. There is a cost-to-value ratio to consider and at some point you will have diminishing returns or are just wanting to spend money--Nothing wrong with that either if you have it to burn.  

[Zen Traveler]

I posted on the first page a link specifically for the RF-7IIs and here is one regarding external amplification with my setup: https://www.avsforum.com/forum/91-audio-theory-setup-chat/1532635-would-i-benefit-external-amp.html

[JefDC]

 

It is certainly no 'audiophile pig slop' but physics - an amplifier must (be able to) deliver what is requested by the load. 

As a loudspeaker presents a reactive load (inductive and/or capacitive - meaning current has to be delivered out of phase with the voltage) the situation is actually even worse as the amplifiers are measured with a resistive load.

 

But I see arguments arise which cannot be solved through the keyboard, the easiest solution is to borrow an amplifier and see whether it makes a difference in a particular situation.

 

With subwoofers the discussion changes completely off course as dedicated amplifiers are used and the main amplifier is released from the burden.

 

 

 

 

 

 

Edited March 18, 2019 by JefDC
Grammar

[pzannucci]

15 minutes ago, JefDC said:

 

It is certainly no 'audiophile pig slop' but physics - an amplifier must (be able to) deliver what is requested by the load. 

As a loudspeaker presents a reactive load (inductive and/or capacitive - meaning current has to be delivered out of phase with the voltage) the situation is actually even worse as the amplifiers are measured with a resistive load.

 

But I see arguments arise which cannot be solved through the keyboard, the easiest solution is to borrow an amplifier and see whether it makes a difference in a particular situation.

 

With subwoofers the discussion changes completely off course as dedicated amplifiers are used and the main amplifier is released from the burden.

 

 

 

 

 

 

If I have a speaker that is rated to 30hz with 2 10" woofers each, they should be able to produce prodigious bass when needed.  I know I had tuned 2 klf-20 10" woofers in 5cf tuned to 33hz boxes and they were capable of shaking the cement foundation.  I am assuming the RF7's should two if balanced with the highs appropriately and driven with enough damping/current.

[robert_kc]

I think there’s been good discussion in this thread.  I’ll be interested in hearing the OP’s results if he tries a different amp.

 

FWIW, following are my thoughts.

 

OP:  You say that you listen to “classic jazz from the 50's”.  It seems to me that this is one of the least demanding music genres for a hi-fi system to recreate.

 

Is your goal to feel your body being assaulted by low frequencies (i.e., “kick your chest”), or recreate in your home a live performance of 1950s era jazz?  

 

FWIW, I’ve never experienced “natural music” (i.e., classical, chamber music, jazz, big band) “kicking me in the chest”.  I attend more than 20 live classical music performances each year, including large-scale orchestral music - and I’m in awe of the power of large-scale orchestral music.  However, large scale orchestral music doesn’t involve “kicking me in the chest” – even though a bass drum (and six double bass) in the symphony hall can be very powerful.  As a point of reference, I’ve heard live performances in a world-class symphony hall of Mahler Symphony 2, Saint-Saëns Symphony No. 3 (Organ Symphony), Beethoven Symphony 9, Brahms German Requiem, and many other large-scale powerful works that greatly exceed the power of a jazz quartet.    I suggest that if you want to challenge your hi-fi system with powerful music, get a hi-res recording (e.g., 24bit/192kHz FLAC download) of Bach’s Toccata and Fugue in D minor and crank it up to the volume level of a live performance from a large pipe organ (e.g., the Wanamaker organ).   In terms of demand on a hi-fi system, “classic jazz from the 50's” is far less demanding in comparison.   (No disrespect intended towards you by calling your music wimpy.  😊    )

 

$64k question:  Do you attend live performances of the music you like?  Does this form your benchmark for music reproduced via your home hi-fi system?   How does your RF-7II perform in comparison to your recollection of live jazz?  FWIW, this is how I think you should judge the sound from your home hi-fi system.

 

FYI, there are people on this forum who use Klipschorn with 3wpc SET amps to listen to jazz.   RF-7II are 4dB less sensitive, so – painting in broad brush strokes - double the power required.   In an average size room at sane listening volumes, I’d say that the RF-7II can deliver a realistic simulacrum of a live jazz performance with a tube amp rated at 10wpc, because there’s little dynamic range to jazz.   (I don’t listen to jazz, but my RF-7II can successfully recreate big-band music with an 8wpc single-ended-pentode tube amp.  For large-scale orchestral music (which has far greater dynamic range), a 30wpc tube amp works well.)

 

If you’re dissatisfied with the bass from RF-7II for jazz, then something seems amiss with your hi-fi system, or you have a problem with room modes (try moving your listening position backwards or forwards), or … candidly … perhaps the problem is with your expectations.   (No offense intended.)  In light of the fact that RF-7II are – relatively speaking - “big boy” speakers, they should provide ample acoustic power in an average size room for 1950s era jazz without worrying about a “high current” amp.  My advice:  get a 6L6GC based PP tube amp with tone controls, and you can enjoy natural timbre, and tailor the frequency balance to your liking.

 

OTOH, a subwoofer is useful for hi-res recordings of large-scale orchestral music, and pipe organ, particularly in a large room, and/or if you listen at “ear-bleed” listening volumes.   And, multiple subwoofers are indicated if you want to “feel” the concussion of explosions in a Blu-ray movie “slamming against your body” - or feel the room shake during a buffalo stampede or earthquake scene in a movie.

 

Where do you live?  Perhaps it would be useful for you to hear your music on someone else’s RF-7IIs that are “dialed in”.

 

Bottom line:  If you’re happy with your RF-7II with a subwoofer, why not just “crank up” your sub?

 

Your thoughts?

 

P.S.    In my basement system I have no problems with dynamics or deep bass, for any music.  

 

Front, center, and left speakers are Klipsch RF-7 II.  A single rear speaker is a Klipsch RF-7.   Subwoofers:  SVS SB16-Ultra, Klipsch R-115SW.  Source:  Oppo UDP-205. 

 

I have multiple tube amps in this system.   If I use a Scott 296 to drive the left and right channels, and a Fisher KX-200 (or Scott 272) to drive the center and (single) rear channel, there is dynamic range and frequency range approaching symphony hall experience.    No problems with dynamics, or deep bass, for any genre of music.  As I mentioned above, the subwoofers are useful for hi-res recordings of large-scale orchestral music, and pipe organ.

[Codyred]

The Anthem 225 I've been trying out has started to come around!  Had it here for a week and its been powered on most of the time. Now the sound of the RF 7II's has begun to fill in along with some bass. In fact, it's more fullness from the RF7II's than I've heard from them in the 5 years I've owned them. I purchased the Anthem used and the previous owner had a set of Mundorf AG caps installed to replace the stock Nichicon caps.  In discussions with the previous owner, apparently those Mundorf caps only had about 75 hours on them, so it seems that may have not been enough time for them to fully form and settle. All I know, is that between yesterday and today, suddenly a new weight to the sound has appeared from the RF7II's that I never heard before.  And I've had a lot of different and integrateds in front of those speakers before.  NAD M2, Yamaha AS2000, HK 990, NAD C375BEE. But this Anthem has the most power and current.  The control it has is there. Now I'm experiencing some listener fatigue from the horn-- geez! there's always something!

 

By the way Zen, I looked at the link you posted, and you have a beautiful home and fabulous speakers!  

[Codyred]

 

1 hour ago, robert_kc said:

I think there’s been good discussion in this thread.  I’ll be interested in hearing the OP’s results if he tries a different amp.

 

FWIW, following are my thoughts.

 

OP:  You say that you listen to “classic jazz from the 50's”.  It seems to me that this is one of the least demanding music genres for a hi-fi system to recreate.

 

Is your goal to feel your body being assaulted by low frequencies (i.e., “kick your chest”), or recreate in your home a live performance of 1950s era jazz?  

 

FWIW, I’ve never experienced “natural music” (i.e., classical, chamber music, jazz, big band) “kicking me in the chest”.  I attend more than 20 live classical music performances each year, including large-scale orchestral music - and I’m in awe of the power of large-scale orchestral music.  However, large scale orchestral music doesn’t involve “kicking me in the chest” – even though a bass drum (and six double bass) in the symphony hall can be very powerful.  As a point of reference, I’ve heard live performances in a world-class symphony hall of Mahler Symphony 2, Saint-Saëns Symphony No. 3 (Organ Symphony), Beethoven Symphony 9, Brahms German Requiem, and many other large-scale powerful works that greatly exceed the power of a jazz quartet.    I suggest that if you want to challenge your hi-fi system with powerful music, get a hi-res recording (e.g., 24bit/192kHz FLAC download) of Bach’s Toccata and Fugue in D minor and crank it up to the volume level of a live performance from a large pipe organ (e.g., the Wanamaker organ).   In terms of demand on a hi-fi system, “classic jazz from the 50's” is wimpy in comparison.   (No disrespect intended towards you by calling your music wimpy.  😊    )

 

$64k question:  Do you attend live performances of the music you like?  Does this form your benchmark for music reproduced via your home hi-fi system?   How does your RF-7II perform in comparison to your recollection of live jazz?  FWIW, this is how I think you should judge the sound from your home hi-fi system.

 

FYI, there are people on this forum who use Klipschorn with 3wpc SET amps to listen to jazz.   RF-7II are 4dB less sensitive, so – painting in broad brush strokes - double the power required.   In an average size room at sane listening volumes, I’d say that the RF-7II can deliver a realistic simulacrum of a live jazz performance with a tube amp rated at 10wpc, because there’s little dynamic range to jazz.   (I don’t listen to jazz, but my RF-7II can successfully recreate big-band music with an 8wpc single-ended-pentode tube amp.  For large-scale orchestral music (which has far greater dynamic range), a 30wpc tube amp works well.)

 

If you’re dissatisfied with the bass from RF-7II for jazz, then something seems amiss with your hi-fi system, or you have a problem with room modes (try moving your listening position backwards or forwards), or … candidly … perhaps the problem is with your expectations.   (No offense intended.)  In light of the fact that RF-7II are – relatively speaking - “big boy” speakers, they should provide ample acoustic power in an average size room for 1950s era jazz without worrying about a “high current” amp.  My advice:  get a 6L6GC based PP tube amp with tone controls, and you can enjoy natural timbre, and tailor the frequency balance to your liking.

 

OTOH, a subwoofer is useful for hi-res recordings of large-scale orchestral music, and pipe organ, particularly in a large room, and/or if you listen at “ear-bleed” listening volumes.   And, multiple subwoofers are indicated if you want to “feel” the concussion of explosions in a Blu-ray movie “slamming against your body” - or feel the room shake during a buffalo stampede or earthquake scene in a movie.

 

Where do you live?  Perhaps it would be useful for you to hear your music on someone else’s RF-7IIs that are “dialed in”.

 

Bottom line:  If you’re happy with your RF-7II with a subwoofer, why not just “crank up” your sub?

 

Your thoughts?

 

P.S.    In my basement system I have no problems with dynamics or deep bass, for any music.  

 

Front, center, and left speakers are Klipsch RF-7 II.  A single rear speaker is a Klipsch RF-7.   Subwoofers:  SVS SB16-Ultra, Klipsch R-115SW.  Source:  Oppo UDP-205. 

 

I have multiple tube amps in this system.   If I use a Scott 296 to drive the left and right channels, and a Fisher KX-200 (or Scott 272) to drive the center and (single) rear channel, there is dynamic range and frequency range approaching symphony hall experience.    No problems with dynamics, or deep bass, for any genre of music.

Wow Robert, what a post! Thanks for taking the time!  No, I don't want bass that hits me in the chest. I have attended live jazz performances before, but not lately. I simply used a comment from another owner who made that statement as an example that the RF7II's can produce significant bass. I do want to hear the bass that happen in the music.  I never expect to hear hard hitting bass with the music I listen to.  Mostly I'm hearing an upright acoustic bass in my music.  But things with the Anthem 225 are improving.  Now I'm wondering if the aftermarket caps previously installed in the amp will continue to improve the bass and smooth things out in the highs from the horn.  I have been trying to hear what the bass will do sans sub with a new amp, but what others have said is true, they will produce more bass than I heard before! I will eventually connect my subwoofer.  

[Codyred]

 Going to start a new thread

[willland]

13 hours ago, Codyred said:

 Going to start a new thread

Well, where is it?

 

Bill

[Codyred]

Will, I just posted it. Thanks

[willland]

4 minutes ago, Codyred said:

Will, I just posted it. Thanks

I saw, if my patience could have have held on for 2 minutes longer.

 

Bill