4.0 AVR and external amplifier

[Old new Guy audio]

I've been trying to get a little help I have the equipment already and I'm trying to get the best setup with what I have Harmon kardon AVR 3700 and a servo 260 2 channel pro studio amp I'm set on 4 full range towers for audio listening only I have 2 Polk Rtia7s 89db and Klipsch vf36 96 db and I know that the Klipsch require less wattage what I'm not sure of is if I run the servo on the front main channels witch set to run which set of towers the Harmon says it will produce 140 a channel in 2 channel stereo and 125 in 4.0 and the rates 130at 6 and 105 at 8 I'm trying to get a answer I am planning on running the rtis with the Harmon but not sure???

 

[PENG]

I've been trying to get a little help I have the equipment already and I'm trying to get the best setup with what I have Harmon kardon AVR 3700 and a servo 260 2 channel pro studio amp I'm set on 4 full range towers for audio listening only I have 2 Polk Rtia7s 89db and Klipsch vf36 96 db and I know that the Klipsch require less wattage what I'm not sure of is if I run the servo on the front main channels witch set to run which set of towers the Harmon says it will produce 140 a channel in 2 channel stereo and 125 in 4.0 and the rates 130at 6 and 105 at 8 I'm trying to get a answer I am planning on running the rtis with the Harmon but not sure???

From the AVR3700's spec sheet:

Audio Section • Stereo mode continuous average power: 125 watts/ch, 20Hz – 20kHz, <0.07% THD, both channels driven @ 8 ohms, 6-ohm certified • Multichannel power: 125 watts/ch, 20Hz – 20kHz, <0.07% THD, two channels driven @ 8 ohms, 6-ohm certified • Bandwidth @ 1W (+0dB/–3dB): 10Hz – 130kHz • Input sensitivity/impedance (line-in): 200mV/47k ohms • Signal-to-noise ratio (IHF-A): 100dB • Adjacent channel separation Dolby Pro Logic® I/II: 40dB Dolby Digital: 55dB DTS: 55dB High instantaneous current capability (HCC): ±45 amps Transient intermodulation distortion (TIM): Unmeasurable Slew rate: 40V/μsec

Such kind of manufacturer's specs are largely meaningless as many details are missing, in this case, it seems BS based... Not picking on HK, others do that kind of things too. If you can find some bench test measurements it may, or may not help that much either as it depends on how/what the reviewer did the measurements.

With such vague and seemingly bs style information, if you want to be on the conservative side, assuming this thing can power 8 ohm nominal speakers if based on you listening habit and environment you need less than 100 W, or 50 W if your speakers are 4 ohm nominal. That's based on the so called "continuous rating". For short term peak moments, it could do more and for very sort duration, a lot more for sure. So how it would perform with the RTia7 would depend a lot on the media contents you listen to as well.

To find out how much power you need, just roughly, use the following calculator:

Peak SPL Calculator (hometheaterengineering.com)

 

[Verdinut]

From the AVR3700's spec sheet:

Audio Section • Stereo mode continuous average power: 125 watts/ch, 20Hz – 20kHz, <0.07% THD, both channels driven @ 8 ohms, 6-ohm certified • Multichannel power: 125 watts/ch, 20Hz – 20kHz, <0.07% THD, two channels driven @ 8 ohms, 6-ohm certified • Bandwidth @ 1W (+0dB/–3dB): 10Hz – 130kHz • Input sensitivity/impedance (line-in): 200mV/47k ohms • Signal-to-noise ratio (IHF-A): 100dB • Adjacent channel separation Dolby Pro Logic® I/II: 40dB Dolby Digital: 55dB DTS: 55dB High instantaneous current capability (HCC): ±45 amps Transient intermodulation distortion (TIM): Unmeasurable Slew rate: 40V/μsec

Such kind of manufacturer's specs are largely meaningless as many details are missing, in this case, it seems BS based... Not picking on HK, others do that kind of things too. If you can find some bench test measurements it may, or may not help that much either as it depends on how/what the reviewer did the measurements.

With such vague and seemingly bs style information, if you want to be on the conservative side, assuming this thing can power 8 ohm nominal speakers if based on you listening habit and environment you need less than 100 W, or 50 W if your speakers are 4 ohm nominal. That's based on the so called "continuous rating". For short term peak moments, it could do more and for very sort duration, a lot more for sure. So how it would perform with the RTia7 would depend a lot on the media contents you listen to as well.

To find out how much power you need, just roughly, use the following calculator:

Peak SPL Calculator (hometheaterengineering.com)

Are you referring to Denon AVR-X3700H's audio specs? You seem to have more complete info than me. But in my owner's manual, it's only rated at 105 watts, 20 Hz -20kHz with 0.08% T.H.D. for an 8 ohm load for 2 channels driven.

 

[PENG]

Are you referring to Denon AVR-X3700H's audio specs? You seem to have more complete info than me. But in my owner's manual, it's only rated at 105 watts, 20 Hz -20kHz with 0.08% T.H.D. for an 8 ohm load for 2 channels driven.

No, the OP's the Harman Kardon AVR3700, not Denon.

 

[Verdinut]

No, the OP's the Harman Kardon AVR3700, not Denon.

Confusing! There are so many possibilities and different manufacturers don't have to use same model numbers. I guess most of them don't usually verify what the others have been using.

 

[lovinthehd]

From what I can see of the limited specifications for your avr and (Samson?) amp specs, the avr is perhaps slightly more powerful. Not in a particularly meaningful way, tho. Maybe use the power amp just to relieve the avr's power supply somewhat....maybe the more sensitive speakers on the avr's amps (keep in mind Klipsch sensitivity specs tend to be an "in-room" equivalent and often you need to adjust their sensitivity spec downward by about 5dB to get to what others are doing.

 

[PENG]

From what I can see of the limited specifications for your avr and (Samson?) amp specs, the avr is perhaps slightly more powerful. Not in a particularly meaningful way, tho. Maybe use the power amp just to relieve the avr's power supply somewhat....maybe the more sensitive speakers on the avr's amps (keep in mind Klipsch sensitivity specs tend to be an "in-room" equivalent and often you need to adjust their sensitivity spec downward by about 5dB to get to what others are doing.

You probably know I am not a fan of using the so called external power amps with the upper midrange AVR typically rated at least 100 WPC, 20-20,000 Hz at THD+N less than 0.1%. I do often suggest the use of real power amps rated at least 200 WPC 8 ohms and 300 WPC 4 ohms 20-20,000 Hz THD+N <0.05%. Such power amps would guarantee 3 dB more SPL under most use conditions, and their 4 ohm ratings are believable, and should be able to drive 4 ohm nominal, with dips to as low as 2.5 ohms as long as the users don't need to push their amps too close to their clipping point.

The Denon AVR-A1H, is probably the only AVR, since the time of those AVR-5803, 5805, 5308, Yamaha RX-Z9, RX-Z11, Onkyo TX-SR805, SR875, 876, NR5008, Integra DTR-8.8 that can be paired with 4 ohm nominal full range speakers configured in 2.1, even up to 5.1.

That being said, if the user (we don't know in this case as we don't know the OP's listening habits, distance and his speaker specs) has the need to push his fairly expensive A1H close to its clipping point, for another $1,000 to 1,500 he may still benefit from using a 2 or 3 channel power amp in terms of clean power during the peaks and at the minimum, potentially longevity as well.

So, like you, and ADTG, I am not one who would waste time and money on external amps when there is no need, no case for them. The Op may or may not benefit from further spending on electronics, but if there is, he would have plenty of good choices, as the A1H has excellent preamp/dac quality, and high enough voltage for just about any external power amps including those low cost Hypex, Purifi based modules that tend to have about 3 dB lower gain than the AVR internal amps.

 

[lovinthehd]

You probably know I am not a fan of using the so called external power amps with the upper midrange AVR typically rated at least 100 WPC, 20-20,000 Hz at THD+N less than 0.1%. I do often suggest the use of real power amps rated at least 200 WPC 8 ohms and 300 WPC 4 ohms 20-20,000 Hz THD+N <0.05%. Such power amps would guarantee 3 dB more SPL under most use conditions, and their 4 ohm ratings are believable, and should be able to drive 4 ohm nominal, with dips to as low as 2.5 ohms as long as the users don't need to push their amps too close to their clipping point.

The Denon AVR-A1H, is probably the only AVR, since the time of those AVR-5803, 5805, 5308, Yamaha RX-Z9, RX-Z11, Onkyo TX-SR805, SR875, 876, NR5008, Integra DTR-8.8 that can be paired with 4 ohm nominal full range speakers configured in 2.1, even up to 5.1.

That being said, if the user (we don't know in this case as we don't know the OP's listening habits, distance and his speaker specs) has the need to push his fairly expensive A1H close to its clipping point, for another $1,000 to 1,500 he may still benefit from using a 2 or 3 channel power amp in terms of clean power during the peaks and at the minimum, potentially longevity as well.

So, like you, and ADTG, I am not one who would waste time and money on external amps when there is no need, no case for them. The Op may or may not benefit from further spending on electronics, but if there is, he would have plenty of good choices, as the A1H has excellent preamp/dac quality, and high enough voltage for just about any external power amps including those low cost Hypex, Purifi based modules that tend to have about 3 dB lower gain than the AVR internal amps.

I think you got your threads mixed up a bit, the OP here doesn't have the A1H but rather the HK AVR3700. He apparently already has the power amp in this case, too (which I think is the Samson Servo 260).

 

[Tulonarinchu]

To make the best use of your equipment, you could consider running the Klipsch VF36 towers with your Harmon Kardon AVR 3700, as they require less wattage and have a higher sensitivity rating. This setup should provide you with good sound quality. The Polk RTiA7 towers can be used with the Servo 260 2-channel amp, taking advantage of its power and potentially enhancing your audio experience. Experiment with different configurations to see which combination suits your listening preferences best. Enjoy your audio setup!