Home theater amp advice...

[everettT]

I have to agree. I love that they utilize SB Acoustics beryllium domes. These have some of the best sound characteristics I have ever seen. In fact the whole Satori line looks awesome. This would have to be one to have on the short list. Since I have all speakers with ribbons I am also drawn to the Salk with RAAL ribbons which may closely match my Ascend Acoustics Horizon center with RAAL 70-20. Yes, this sends me down a bad path. I may have to hate you for enticing me with these. I have spoken with Jim once in the recent past on these and yeah, he seems so real to deal with. It is tough to decide between the beryllium domes and RAAL ribbons. As I am looking to have great sound with very solid output, I am looking at the higher sensitivity units. The SS8's draw me in like a moth to a flame. Really like the passive use to assist the output of 8's while not having a boomy sound and port issues. How are he mids? I'll bet they are fantastic. Nevermind, I know the answer. Everything about this speaker is righteous.

The midrange is a delightful and as you are probably aware, the Be and Raal can be interchanged upon request.

 

[AcuDefTechGuy]

Before I opt for new speakers I would require two things. 1. The new ones should sound better than these. I have looked around a lot and this first prerequisite has been very difficult to obtain. The only ones that have come close are the Revel's and the Focal's that I listened to. The Focals are quite bright but am intrigued with the sound. I am quite curious of the Legacy Aeris I think this would perform quite well but have not heard these. I have found B&W to be too bright and fatiguing. 2. This is the more difficult one to achieve. The very slight improvement in sound has come at a price that is objectionable to me. I do not wish to part with these for the 1000-1500 that I may receive for used only to pay 25-30,000 or more to replace. I would rather just drive these properly.

Yeah, you're right. Big difference between deserving new speakers vs actually paying for them.

The Yamaha CX-A5200 is awesome, so congrats on that!

I absolutely love my CX-A5100 and MX-A5000 (500W x 2 Ch into 2 ohms Dynamic Power).

As for amps, I think ATI (or one of their many clones) would be my choice.

I remember The Audio Critic reviewing the ATI 60WPC amp, and it was cranking out plenty of power even down to 1 ohm.

So I bet an ATI 300WPC (or one of their clones) could power just about anything down to 1 ohm.

I think the ATI 200WPC amp could too (or one of their many clones).

 

[AcuDefTechGuy]

Let me finish by saying that I also agree that I deserve new speakers. I will need a GoFundMe account to make this happen. Will you be the first to pitch in?

As for funding your HT, I have a personal HT fund for MYSELF.

I think we all deserve a personal HT fund. I put $250 per month into my HT fund.

If you had put $100 per month into your HT fund x 30 years = $36,000.

But I see your point completely regarding diminishing returns.

Even if you had $36,000 in your personal HT fund, why spend $20-$30K if the speakers don't sound any better than your speakers?

 

[PENG]

Before I opt for new speakers I would require two things. 1. The new ones should sound better than these. I have looked around a lot and this first prerequisite has been very difficult to obtain. The only ones that have come close are the Revel's and the Focal's that I listened to. The Focals are quite bright but am intrigued with the sound. I am quite curious of the Legacy Aeris I think this would perform quite well but have not heard these. I have found B&W to be too bright and fatiguing. 2. This is the more difficult one to achieve. The very slight improvement in sound has come at a price that is objectionable to me. I do not wish to part with these for the 1000-1500 that I may receive for used only to pay 25-30,000 or more to replace. I would rather just drive these properly.

So for me, I would really prefer for now to run these and enjoy them while powering up the rest of the system with a suitable power supply. As always I appreciate the advise. I am hoping that I will get some input to my original question. Let me finish by saying that I also agree that I deserve new speakers. I will need a GoFundMe account to make this happen. Will you be the first to pitch in?

Going by the impedance graph, if you are going to keep those amp killer speakers, a more affordable way to do it instead of spending thousands on the JC1 that may barely adequate, is to get a good subwoofer and set the crossover to 80 Hz. Then you can simply drive the speakers with a proamp such as the following:

QSC DCA1622
Crown XLS 1502

I have no experienced with them but @lovinthehd and @Verdinut, will tell you how well those amps perform in the real world, and based on specs and their reputations, I believe they are designed for transparency, that is, no build in predetermined sound signatures.

Or you can go with some relatively low cost regular amps such as the Anthem MCA 325, ATI 4002, Monolith 2X200 etc. @AcuDefTechGuy can tell you about the ATI amp and I can tell you the Anthem is as good as anything money can buy in terms of transparency/accuracy.

The JC1s are nice, with superior specs on paper and excellent build quality for sure, but audible sound quality difference? I don't think so as I can see no reasons for that to happen, but if you believe it then good for you.

 

[PENG]

Another error in the original literature was the sensitivity was listed at 102 db which is clearly wrong but some have suggested that they are at a more normal 88-89 db sensitivity. The seated position is 15 feet from speakers. The rated power handling is 60-340 rms.

Thank you for the feedback, now this is getting interesting when you mentioned "Another error.....".

If it is the RS9 Kappa:

Then according to the spec sheet:



If the information is accurate then the speaker should not be too hard to drive, but obviously can still be an amp killer if you pair them with an average 200/300 W 8/4 ohm amp especially if it has poor phase angle vs frequency response, that we cannot comment without seeing the graph.

Also, if the schematic diagram (found online) of the crossover is accurate, then the impedance graph you posted is showing something quite different. For example, the calculated impedance should be at least 2.6 to 4 ohms, not 0.8 ohms as shown by the graph. Would you mind sharing the source of that impedance graph?

 

[AcuDefTechGuy]

if you are going to keep those amp killer speakers

LOL.

What's amazing to me is that he's been using a YAMAHA AVR to power these 1-ohm (min Impedance) speakers for the last 30 YEARS!!!!!!

Go YAMAHA!!!

I knew Yamaha AVRs are rated for Dynamic Power of 2 ohms, but hey, 1 ohm also works!

Maybe the Yamaha MX-A5000 (clearance sale) or MX-A5200 or Yamaha PX3 amps will work.

The Yamaha MX amps actually has a feature that allows bi-amping without the need of Y-Cables (not that I recommend any passive bi-amp ).

 

[snakeeyes]

LOL.

What's amazing to me is that he's been using a YAMAHA AVR to power these 1-ohm (min Impedance) speakers for the last 30 YEARS!!!!!!

Go YAMAHA!!!

I knew Yamaha AVRs are rated for Dynamic Power of 2 ohms, but hey, 1 ohm also works!

Maybe the Yamaha MX-A5000 (clearance sale) or MX-A5200 or Yamaha PX3 amps will work.

The Yamaha MX amps actually has a feature that allows bi-amping without the need of Y-Cables (not that I recommend any passive bi-amp ).

Curious if MX-A5000 and MX-A5200 specs are identical?

 

[PENG]

LOL.

What's amazing to me is that he's been using a YAMAHA AVR to power these 1-ohm (min Impedance) speakers for the last 30 YEARS!!!!!!

Go YAMAHA!!!

I knew Yamaha AVRs are rated for Dynamic Power of 2 ohms, but hey, 1 ohm also works!

Maybe the Yamaha MX-A5000 (clearance sale) or MX-A5200 or Yamaha PX3 amps will work.

The Yamaha MX amps actually has a feature that allows bi-amping without the need of Y-Cables (not that I recommend any passive bi-amp ).

I bet it will work too, as long as the volume turned to the right places.

 

[AcuDefTechGuy]

Curious if MX-A5000 and MX-A5200 specs are identical?

The Power output specs look the same. For example, both have a Dynamic Power output of 500 Watts x 2Ch into 2 ohms. For both, the 20Hz-20kHz 0.06% THD power is 150W x 2Ch into 8 ohms.

I think the biggest difference is that you can Bridge four of the Channels in the MX-A5200. The 20Hz-20kHz 0.06% THD power goes from 150W x 2Ch to 200W x 2Ch into 8 ohms when Bridged.

I don't know how much the Dynamic Power goes up to.

On the MX-A5000, you cannot Bridge any Channels.

 

[03kbredfire]

Thank you for the feedback, now this is getting interesting when you mentioned "Another error.....".

If it is the RS9 Kappa:

Then according to the spec sheet:

View attachment 28129

If the information is accurate then the speaker should not be too hard to drive, but obviously can still be an amp killer if you pair them with an average 200/300 W 8/4 ohm amp especially if it has poor phase angle vs frequency response, that we cannot comment without seeing the graph.

Also, if the schematic diagram (found online) of the crossover is accurate, then the impedance graph you posted is showing something quite different. For example, the calculated impedance should be at least 2.6 to 4 ohms, not 0.8 ohms as shown by the graph. Would you mind sharing the source of that impedance graph?

The other error is in response to someone mentioning that this was a terrible design speaker. If it is an error to design with this low of an impedance it is also wrong to have misguided SPL specs. 4-6 ohm is nominal as all speakers are generally rated in nominal impedance. The dips and the dynamics from music are what drive tremendous current demands and can kill amps. These were the last year of build and on such, a switch was installed to mitigate the impedance dip at the expense of sonic purity. I am thankful that the switch exists as it has allowed me to enjoy speakers for years. The graph was one I had found years ago when investigating the speakers. I have found others which are quite similar. I chose this as it shows complete resistance dips. The other more commonly found graph shows a clipped response and slightly different area of frequency response as to where the dip happens. I have mentioned the switch on several posts so I will share the schematic for those interested. This shows the variable crossover for the fine tuning at all crossover points as well as the 1 ohm 50watt resistor. I feel it was a great design for 30 years ago. I have toyed with variable setpoints but felt it unnecessary to alter greatly from nominal factory set. It has he look and function of Genesis audio speaker, as it should since both companies were founded by the same individual.

 

[03kbredfire]

As for funding your HT, I have a personal HT fund for MYSELF.

I think we all deserve a personal HT fund. I put $250 per month into my HT fund.

If you had put $100 per month into your HT fund x 30 years = $36,000.

But I see your point completely regarding diminishing returns.

Even if you had $36,000 in your personal HT fund, why spend $20-$30K if the speakers don't sound any better than your speakers?

To be clear, I was not saying that speakers now do not sound better, I am just saying that the difference in sound quality is either, they do not sound better or the difference is so slight as to not be worth any additional expenditure. I have too many hobbies and not enough money to continually have the upgrade bug. But it has been 30 years with these and it is much easier nowadays to sell used good gear than it used to be. So I always consider my options.

 

[PENG]

The other error is in response to someone mentioning that this was a terrible design speaker. If it is an error to design with this low of an impedance it is also wrong to have misguided SPL specs. 4-6 ohm is nominal as all speakers are generally rated in nominal impedance. The dips and the dynamics from music are what drive tremendous current demands and can kill amps. These were the last year of build and on such, a switch was installed to mitigate the impedance dip at the expense of sonic purity. I am thankful that the switch exists as it has allowed me to enjoy speakers for years. The graph was one I had found years ago when investigating the speakers. I have found others which are quite similar. I chose this as it shows complete resistance dips. The other more commonly found graph shows a clipped response and slightly different area of frequency response as to where the dip happens. I have mentioned the switch on several posts so I will share the schematic for those interested. This shows the variable crossover for the fine tuning at all crossover points as well as the 1 ohm 50watt resistor. I feel it was a great design for 30 years ago. I have toyed with variable setpoints but felt it unnecessary to alter greatly from nominal factory set. It has he look and function of Genesis audio speaker, as it should since both companies were founded by the same individual.
View attachment 28130

That's the schematic diagram I referred to. You can clearing see that the minimum impedance of the LF input is determined by the 2000 uF capacitor. That's why I said the impedance would be 2.6 to 4 ohms, because even if you ignore the impedance of the inductors and resistors, that series capacitor C19 at 30/32 ohm will give you more than 2.6 ohms. You can calculate it yourself using the linked calculator if you don't know the formula. (https://www.allaboutcircuits.com/tools/capacitor-impedance-calculator/)

Given the information in the schematic, It is impossible for the speaker to dip to 0.8 ohm at any frequency if the crossover is included in the measurements. Please note that at the very low frequencies, the impedance of the mid/high freq branches are very high so at such frequencies the impedance of the LF inputs are practically the overall impedance of the speaker, and again, will be at least 2.6-2.7 ohms even if you ignore the impedance of the inductor/resistor branch and the voice coil. That actually happens to be consistent with the specified nominal impedance of 4-6 ohm. There are various claim of what nominal impedance is, one being (ref source: wiki) 1.15 X the minimum impedance.

So one of the following may be the reason(S) for the seemingly contradictory information:

- The schematic diagram is not accurate, or
- Whoever made the measurements and plotted that graph did not do it right or it not accurately, or
- The measurement was done with the crossover bypassed, or
- The speaker was modified, or
- Any combinations of the above.

 

[03kbredfire]

LOL.

What's amazing to me is that he's been using a YAMAHA AVR to power these 1-ohm (min Impedance) speakers for the last 30 YEARS!!!!!!

Go YAMAHA!!!

I knew Yamaha AVRs are rated for Dynamic Power of 2 ohms, but hey, 1 ohm also works!

Maybe the Yamaha MX-A5000 (clearance sale) or MX-A5200 or Yamaha PX3 amps will work.

The Yamaha MX amps actually has a feature that allows bi-amping without the need of Y-Cables (not that I recommend any passive bi-amp ).

I feel the greatest part of the Yamaha gear has been its protection circuitry. I have tested the limits of all gear through these speakers and have had them shut down on many occasions. At one point I pulled the cover off the receiver and placed a box fan on top to eliminate the heating as a source of protection circuitry tripping. They still tripped. I do incorporate bi-amping currently and agree that this is a great feature on the Yamaha gear. The amp was tested at 144 into 8 and 272 into 4 ohm.

 

[03kbredfire]

That's the schematic diagram I referred to. You can clearing see that the minimum impedance of the LF input is determined by the 2000 uF capacitor. That's why I said the impedance would be 2.6 to 4 ohms, because even if you ignore the impedance of the inductors and resistors, that series capacitor C19 at 30/32 ohm will give you more than 2.6 ohms. You can calculate it yourself using the linked calculator if you don't know the formula. (https://www.allaboutcircuits.com/tools/capacitor-impedance-calculator/)

Given the information in the schematic, It is impossible for the speaker to dip to 0.8 ohm at any frequency if the crossover is included in the measurements. Please note that at the very low frequencies, the impedance of the mid/high freq branches are very high so at such frequencies the impedance of the LF inputs are practically the overall impedance of the speaker, and again, will be at least 2.6-2.7 ohms even if you ignore the impedance of the inductor/resistor branch and the voice coil. That actually happens to be consistent with the specified nominal impedance of 4-6 ohm. There are various claim of what nominal impedance is, one being (ref source: wiki) 1.15 X the minimum impedance.

So one of the following may be the reason(S) for the seemingly contradictory information:

- The schematic diagram is not accurate, or
- Whoever made the measurements and plotted that graph did not do it right or it not accurately, or
- The measurement was done with the crossover bypassed, or
- The speaker was modified, or
- Any combinations of the above.

This is the kind of info I was hoping to find when joining this forum. I have enjoyed watching from a distance but it is time to take part. Thanks to Gene and staff for all of their solid reviews and detailed analysis of audio gear. It is the kind of nut and bolts information that most of us tech inspired folks are striving to achieve. The following is the other graph which shows a clipped region in low freq. and not as low of a dip in the higher region. I have to believe that two different tests from different sources with similar results validate the overall impedance characteristics. Slightly different but very close. Thank you for detailed response and consideration of post.

 

[03kbredfire]

I bet it will work too, as long as the volume turned to the right places.

… and the 1 ohm series switch is engaged. If bypassed, it shuts down quickly.

 

[PENG]

… and the 1 ohm series switch is engaged. If bypassed, it shuts down quickly.

I did the calculations for with and without the 1 ohm resistor, results are as follow.

Resistor in circuit:
Total impedance = 4.108 ohms

Resistor bypassed, i.e. switch closed:
Total impedance = 3.935 ohms

That's based on 30 Hz, as frequency increases, the impedance of the series cap would decrease, but the equivalent 12.5 mH and voice coil series and parallel with the 15 mH impedance would increase so at some point, say above 100 Hz, the overall impedance of the LF section will be dominated by the inductance series/parallel circuit.

If it shuts down quickly with that 1 ohm resistor switched out, that means your Yamaha is operating pretty close it's limit for your application. All else remains equal, the JC1 should have no trouble without the resistor in the circuit. Please note that the resistor simply limits the current draw by the woofer so you lose some LF spl, there should be no effects on the mid and high drivers.

Would you not consider using a subwoofer with XO set to 80 Hz? That would allow you to avoid the most serious dip between 20 and 80 Hz. In addition, you can bi-amp at the same time, so the mid/high section will be isolated from the influence of the big woofer. Again, if you do that, there are all kinds of amplifiers that can do a good job for you. I bet those speakers will sound significantly nicer that way.

 

[PENG]

This is the kind of info I was hoping to find when joining this forum. I have enjoyed watching from a distance but it is time to take part. Thanks to Gene and staff for all of their solid reviews and detailed analysis of audio gear. It is the kind of nut and bolts information that most of us tech inspired folks are striving to achieve. The following is the other graph which shows a clipped region in low freq. and not as low of a dip in the higher region. I have to believe that two different tests from different sources with similar results validate the overall impedance characteristics. Slightly different but very close. Thank you for detailed response and consideration of post.
View attachment 28131

I think it came from the same source and someone just play with the scales and magnification. I would trust the first one you posted as that one at least look a little more complete and more professionally presented. The only issue is, not knowing why the low dip, that defies electrical circuit theory.

 

[03kbredfire]

I did the calculations for with and without the 1 ohm resistor, results are as follow.

Resistor in circuit:
Total impedance = 4.108 ohms

Resistor bypassed, i.e. switch closed:
Total impedance = 3.935 ohms

That's based on 30 Hz, as frequency increases, the impedance of the series cap would decrease, but the equivalent 12.5 mH and voice coil series and parallel with the 15 mH impedance would increase so at some point, say above 100 Hz, the overall impedance of the LF section will be dominated by the inductance series/parallel circuit.

If it shuts down quickly with that 1 ohm resistor switched out, that means your Yamaha is operating pretty close it's limit for your application. All else remains equal, the JC1 should have no trouble without the resistor in the circuit. Please note that the resistor simply limits the current draw by the woofer so you lose some LF spl, there should be no effects on the mid and high drivers.

All true. I notice all benefits in the lower range with switch and is quite apparent by crossover as to why that is so. I think you meant to say with the resistor out of the circuit? As the resistor is in series to add load and reduce current demands.

Would you not consider using a subwoofer with XO set to 80 Hz? That would allow you to avoid the most serious dip between 20 and 80 Hz. In addition, you can bi-amp at the same time, so the mid/high section will be isolated from the influence of the big woofer. Again, if you do that, there are all kinds of amplifiers that can do a good job for you. I bet those speakers will sound significantly nicer that way.

Fair question. The crossover for the woofers are reportedly at 80Hz. So if I crossed at 80 then I would essentially be shutting off 4 12" drivers. At that point I should not have these speakers and just get bookshelves. With the new Yamaha pre/pro, I can adjust crossover between speakers. I do not remember what the lowest crossover point is but I could try that. I have currently bypassed the crossover function and just let it eat so to speak. I listen to songs like Boz Scaggs "Thanks to you" or Chris Jones "Long after you're gone" to get a sense of overall tonality. Love the sound with mains running full range. I feel like I would be neutering the speakers by utilizing a XO.

 

[lovinthehd]

Maybe he should have his speakers measured!

 

[03kbredfire]

Maybe he should have his speakers measured!

Really