Looking for feedback/advice on a preamp/processor/receiver choice.

[Zero Snake Oil]

I'm sold for now on giving up XLR and getting more cost effective yet sonically high(er) performing AVR instead of pre/pro. I just ordered a 3700 and should have it in a few days.

Thanks again for everyone's participation. I would still like to explorer remedying my ground loops though. So I will be unhooking the FM antenna and seeing what shakes out and report back what I learn.

 

[Pogre]

I'm sold for now on giving up XLR and getting more cost effective yet sonically high(er) performing AVR instead of pre/pro. I just ordered a 3700 and should have it in a few days.

Thanks again for everyone's participation. I would still like to explorer remedying my ground loops though. So I will be unhooking the FM antenna and seeing what shakes out and report back what I learn.

The 3700 is a great choice. It has excellent measured performance and imo, strikes a good balance between cost, features, power and connectivity. I think you'll be very happy with it.

Good luck with your ground loop. Those can be a bugger to get sorted, but I have a feeling you'll get it licked.

 

[PENG]

I'm sold for now on giving up XLR and getting more cost effective yet sonically high(er) performing AVR instead of pre/pro. I just ordered a 3700 and should have it in a few days.

Thanks again for everyone's participation. I would still like to explorer remedying my ground loops though. So I will be unhooking the FM antenna and seeing what shakes out and report back what I learn.

Okay, but let me at least finish comparing another important distortions, the intermodulation distortions:
Keep in mind two units of the AV7705 were tested, the other (the first sample) did do better in IMD, not quite as good as the 3700, but much closer.

 

[PENG]

I'm sold for now on giving up XLR and getting more cost effective yet sonically high(er) performing AVR instead of pre/pro. I just ordered a 3700 and should have it in a few days.

Thanks again for everyone's participation. I would still like to explorer remedying my ground loops though. So I will be unhooking the FM antenna and seeing what shakes out and report back what I learn.

So it seems that you have seen enough and ordered the 3700, if you ordered your local BB it would be easy to return if it doesn't work out for some reasons.

On the ground loop thing, I would ask you to please read up on the topic and you will see that even using XLR may not totally resolve your current issue.

Slight Buzz RCA to XLR | Audio Science Review (ASR) Forum
AN Dealing with legacy pin 1 problems (hypex.nl)
AN Amplifier signal input wiring (hypex.nl)

NC400 Definitive performance class D amp for DIY - Bing

Intelligent search from Bing makes it easier to quickly find what you’re looking for and rewards you.

www.bing.com

Please download the document and read page 17 through 19.

Once thing you can try quickly is, by using a pair of RCA to XLR cables and use it with the Monolith power amp.
There are at least two or three that are wired correctly and should have the best chance of fixing or at least lowering the hum you are getting. I have used a pair from Monoprice with the balanced inputs of a QSC pro amp and it worked fine too but I would feel more comfortable with the Benchmark cable.

Benchmark RCA to XLRM Adapter Cable for Analog Audio - pin 3 to RCA sh - Benchmark Media Systems
Interconnect Cables | March Audio | Australia
ghentaudio --- A15 Canare L-4E6S RCA to XLR Interconnect Audio Cable

 

[Zero Snake Oil]

So I just read that the AVR-X3700H has become a split model (internally within Denon), meaning some of the components inside have been changed out. Apparently any with serial numbers whose last 5 digits are 70000 or greater have a new formulation that started around May 2021. Evidently this fixes the HDMI 2.1 bug(s) which is great, but it obviously brings forth the possibility that performance may be impacted (or not) compared to earlier designs. It's an open question at this point. Hopefully there is nothing which has changed for the worse, but I read that DAC chips may be different which suggest to me that measured performance would likely be different. It could be insignificantly different or significantly different and for the better or worse.

It appears that most all the independent evaluations and reviews for gear like this tend to be early on after a products introduction; which gets me pondering. Who's to say that mid model changes like this don't happen more often, but go unnoticed because there isn't some noteworthy bug that's addressed or the like? A hard core cynic might wonder if manufacturers would ever stuff higher end parts early on, and then quietly substitute some of them for functionally equivalent but lesser quality ones after the review season is over. For example 1% vs 5% resistors, heat resistance etc. Let's hope not.

 

[PENG]

Zero snake oil, let's just reviewed one more/last graph from the ASR review as this is the one that should put you at ease on the output voltage concern.

The blue and red curves are from the test in preamp mode, and that's the mode you will be using with the Monolith power amp.

You can see that at 2 Vrms output, SINAD is still at about 97 dB, that is 0.0014125 THD+N. Based on the one for the X6700H, even at 4 V, SINAD would still be at around 90 to 92 dB, or 0.0025% THD+N.

The green curves are from the test in non preamp mode, and you can see that at 1.4 V, SINAD is about 100 dB and that is 0.001% THD+N. When it exceeds 1.4 V, SINAD starts to drop and Amir referred to it as "clips" that to me he must have meant the power amplifiers would be clipping at that point, but not the preamp/pre out. For the pre out, yes you can see how the green curve shows SINAD decreasing, but at 2 V SINAD for both channels are still at about 76 dB, that's almost 1 dB better than the AV7705 that is a preamp/processor!! 76 dB SINAD is 0.0158489% THD+N, that is hardly clipping. In fact you can see that the rate of decrease has slowed down when output exceeds about 1.6 V and by the time it hits 2 V, the down slope becomes very gentle. It would probably not decrease much more from 2 V to 4 V. Again, that would be for non preamp mode, that is, the internal power amps will be fully functional, along with the pre outs.

 

[Zero Snake Oil]

So it seems that you have seen enough and ordered the 3700, if you ordered your local BB it would be easy to return if it doesn't work out for some reasons.

On the ground loop thing, I would ask you to please read up on the topic and you will see that even using XLR may not totally resolve your current issue.

Slight Buzz RCA to XLR | Audio Science Review (ASR) Forum
AN Dealing with legacy pin 1 problems (hypex.nl)
AN Amplifier signal input wiring (hypex.nl)

NC400 Definitive performance class D amp for DIY - Bing

Intelligent search from Bing makes it easier to quickly find what you’re looking for and rewards you.

www.bing.com

Please download the document and read page 17 through 19.

Once thing you can try quickly is, by using a pair of RCA to XLR cables and use it with the Monolith power amp.
There are at least two or three that are wired correctly and should have the best chance of fixing or at least lowering the hum you are getting. I have used a pair from Monoprice with the balanced inputs of a QSC pro amp and it worked fine too but I would feel more comfortable with the Benchmark cable.

Benchmark RCA to XLRM Adapter Cable for Analog Audio - pin 3 to RCA sh - Benchmark Media Systems
Interconnect Cables | March Audio | Australia
ghentaudio --- A15 Canare L-4E6S RCA to XLR Interconnect Audio Cable

I really appreciate your willingness to help like this. I see there are lots of references here with web results or PDF targets. Can you point me to which one which the pp.17-19 refers? I plan to peruse all of what is provided but it could take some time, and I want to read the 17-19 you particularly stressed 1st.

 

[PENG]

I really appreciate your willingness to help like this. I see there are lots of references here with web results or PDF targets. Can you point me to which one which the pp.17-19 refers? I plan to peruse all of what is provided but it could take some time, and I want to read the 17-19 you particularly stressed 1st.

Let me know if it works.

 

[Zero Snake Oil]

Gotcha. The NC400 amp document. Already have it loaded in Okular.

 

[Golfx]

Regarding Denon and the split production. I have been quite proud of how Denon has handled the HDMI 2.1 buggy chip from Panasonic. If you look at how they responded they produced an external box to fix, for free, the Xbox gamer disconnect (small fraction of customers) for those early adopters who bought the first production of the buggy chips. Then they “placed” into production an internal fix in the second part of production for the “split” manufacture. All of this cost them profits—probably lost money to maintain customer respect. You don’t spend all that time planning, designing and preparing production contracts for an initial manufacture and then switch to cheaper less capable parts. This huge change order at the build factory would quickly wind up costing them much much more than any savings gained by substituting lesser capable parts. Denon has a reputation for reliable AVRs and quickly addressing unforeseen bugs. I have great sympathy for the early purchasers of Anthem’s and Arcam’s new line of AVPs/AVRs fraught with bugs and bad customer relation decisions. You lose trust—kind of like a new car stopping in the middle of an intersection.


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[Zero Snake Oil]

Regarding Denon and the split production. I have been quite proud of how Denon has handled the HDMI 2.1 buggy chip from Panasonic. If you look at how they responded they produced an external box to fix, for free, the Xbox gamer disconnect (small fraction of customers) for those early adopters who bought the first production of the buggy chips. Then they “placed” into production an internal fix in the second part of production for the “split” manufacture. All of this cost them profits—probably lost money to maintain customer respect. You don’t spend all that time planning, designing and preparing production contracts for an initial manufacture and then switch to cheaper less capable parts. This huge change order at the build factory would quickly wind up costing them much much more than any savings gained by substituting lesser capable parts. Denon has a reputation for reliable AVRs and quickly addressing unforeseen bugs. I have great sympathy for the early purchasers of Anthem’s and Arcam’s new line of AVPs/AVRs fraught with bugs and bad customer relation decisions. You lose trust—kind of like a new car stopping in the middle of an intersection.


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I wasn't really criticizing Denon at all. Assuming their changes only help and not hurt anything; I completely agree they have handled things pretty well. It's more I just wanted to point out that it got me thinking about what could happen with any manufacturer. Personally I'm not a fan of changing parts or design of a model without also modifying the name of the model to differentiate it. Something as simple as adding a "v2", "A", or whatever, I think is helpful to keep confusion to a minimum.

 

[Golfx]

Ah that’s good. Confusion is definitely what resulted from faulty chips, Panasonic being sold to new owners, factory fires and Covid. I have sympathy for quality retail sellers like Crutchfield who is losing huge earnings from empty shelves. Hope things turn soon for the better.


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[Verdinut]

Ah that’s good. Confusion is definitely what resulted from faulty chips, Panasonic being sold to new owners, factory fires and Covid. I have sympathy for quality retail sellers like Crutchfield who is losing huge earnings from empty shelves. Hope things turn soon for the better.


Sent from my iPad using Tapatalk

Panasonic is not being sold. They only decided to outsource TV production for the 2022 sets to an external firm:

Panasonic confirms plan to outsource TV production to external partner

TV development will continue

www.flatpanelshd.com

 

[Golfx]

Oh that is a different Panasonic than the former chip manufacturer. Same name—different company.


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[Zero Snake Oil]

@PENG These also seem to have the correct wiring don't you agree?
MP version
If so, they are much more affordable. Or, I could buy some XLR-M ends and build my own. I already have everything I need but for the ends.

 

[Zero Snake Oil]

UPDATE: Disconnecting FM antenna had no effect on ground loop issues.

 

[PENG]

So I just read that the AVR-X3700H has become a split model (internally within Denon), meaning some of the components inside have been changed out. Apparently any with serial numbers whose last 5 digits are 70000 or greater have a new formulation that started around May 2021. Evidently this fixes the HDMI 2.1 bug(s) which is great, but it obviously brings forth the possibility that performance may be impacted (or not) compared to earlier designs. It's an open question at this point. Hopefully there is nothing which has changed for the worse, but I read that DAC chips may be different which suggest to me that measured performance would likely be different. It could be insignificantly different or significantly different and for the better or worse.

It appears that most all the independent evaluations and reviews for gear like this tend to be early on after a products introduction; which gets me pondering. Who's to say that mid model changes like this don't happen more often, but go unnoticed because there isn't some noteworthy bug that's addressed or the like? A hard core cynic might wonder if manufacturers would ever stuff higher end parts early on, and then quietly substitute some of them for functionally equivalent but lesser quality ones after the review season is over. For example 1% vs 5% resistors, heat resistance etc. Let's hope not.

I meant to caution you that but forgot, good thing you found out yourself. I apologize for the oversight. It is unlikely for performance to take much of a hit, but it is possible the new dac may cause THD+N to increase by a couple dB.

They likely have substituted the AK4458 with a comparable ES9006 but that's just my educated guess. That's another reason I think it is better to conserve cash by avoiding the more expensive models. Then save up for your next upgrade in 2023.

If you look at Denon/Marantz's track record in recent years, they have actually substituted parts with better ones, except in this case it is difficult to find a better dac than the AK4458 for the same cost. If I understand right, they have to substitute it because of the shortage resulted from the factory fire. There are conflicting stories too as a couple of ASR members were told by Denon customer support that the AK4458 are still used in the 4700 and 6700.

 

[PENG]

@PENG These also seem to have the correct wiring don't you agree?
MP version
If so, they are much more affordable. Or, I could buy some XLR-M ends and build my own. I already have everything I need but for the ends.

Agreed, I have a pair myself. The Benchmark one looks more impressive though if you can believe their marketing info.

 

[Zero Snake Oil]

Agreed, I have a pair myself. The Benchmark one looks more impressive though if you can believe their marketing info.

After I saw the Benchmark price, my "Snakey Sense" started to tingle. So I started looking at other options and found the MP ones. The MP ones have all the needed quality features such that I doubt that adding anything else would help much, if at all. Unfortunately MP is out of stock right now & Amazon is double the price (which is still cheap compared to the boutique stuff). I'm refering to the 3' lengths which is what would want.

I ordered a couple of Neutrik male XLR ends which I will wire up as depicted in the document you referenced. If they turn out to do the trick I'll probably just order the pre-made MP cables. No sense in me spending the time to do all that soldering if it doesn't somehow get me better quality or save serious money.

 

[Zero Snake Oil]

I want to say that learning about the method to leverage XLR balanced inputs even when using a single ended source, I consider to be one of the shiniest and valuable nuggets if information I've run across in some time. Thanks for that!