What is Floyd Toole saying about extra amplifier power and headroom?

@diamonddupree You should contact FT and ask him.

https://www.linkedin.com/search/results/all/?keywords=Floyd%20Toole%3A%20Acoustical%20consulting%2C%...

@diamonddupree Your post is such an appropriate post for what I was considering doing, that is get an amp with more power at 2 Ohms, the CODA #8 v1, v2, or v3 (600 - 1600 watts depending on version). I actually got some extra cash today for year end and would have been all over a new amp except for the results that happened yesterday. I no longer need a new amp.

I was reading a book on how to fix my issue. I ended up contacting the books author to remotely solve my acoustic issues. Take a look at my post here and to see what was done. Follow the links to see the graphs. This solution used a ROON Convolution file, microphone measurements of my room, and both REW and Audiolense software. Some very advanced stuff which I outsourced the to an expert. He has a business to do this type of work.

https://forum.audiogon.com/discussions/thiel-owners-2/post?postid=2066167#2066167

Send me a A'gon PM if you want to discuss any of this by email. 

@diamonddupree Get the miniDSP UMIK-1 microphone for $100. Then download on a Windows 10 computer REW software. I am not sure if it works on a MAC.

The free REW software will use the calibration file sent with the microphone and setup your mic. The nice thing about this combo is that the REW software has special integration with the miniDSP mic. A real breeze to get going and I had never done this before.

You also need a test signal (maybe called a sweep signal). I used ROON to play the LEFT and RIGHT sweeps, one at a time. Once the data is collected by REW you have a lot of reports available including the SPL report. There are things like mic positioning, where it is pointed, and other things to do. Just contact the guy I referenced in the links and he will have you sorted out very quickly. Idiot proof instructions.

I do not know the answer to your upsampling question but I did stay at a Holiday Inn Express last night and learned something interesting.

1) I received a new Matrix Mini-i-3 Pro DAC yesterday ($899 MSRP)
2) Hooked it up and tried to get ROON via RJ45. Did not work since the ROON Certification is still a few days away.
3) I then used a very bad connection. Toslink from my very noisy computer to the Matrix using the TIDAL and Amazon clients.
4) Played a few songs and I am thinking this is rather good. I get to the 1976 song StarGazer from Rainbow and I am wowed by the sound. The percussion is hitting harder with better decay and it seems like the drummer is in the room. Awesome sound.
5) I switch to my Benchmark DAC3B ($1700 MSRP) on the better input of my preamp. It is connected to ROON with a microRendu. My best setup.
6) The same tracks are not the same sounding, It sounds more mellow and boring in comparison.
7) Only difference I can tell is that I have UPSAMPLING to 192 turned on on ROON. I turn it off and now only have my Convolution filter enabled. Boom, the excitement factor in the music is turned on instantly. Sounds as good as the Matrix, better in fact because of the better connectivity I have used.

End result is that I am no longer upsampling on ROON. Maybe that upsampling is not very good or I just prefer no upsampling.

Just an FYI.

@diamonddupree I was referring to the MiniDSP UMIK-1 microphone and not any DAC. This mic is tightly integrated with the REW software.

@diamonddupree Get the miniDSP UMIK-1 microphone for $100. Then download on a Windows 10 computer REW software. I am not sure if it works on a MAC.

@diamonddupree Here is a post that is related to your original question.

https://www.whatsbestforum.com/threads/coda-no-16-amplifier.31078/page-2 (post #22).

I am interested in the same amp as this guy. It looks like this guy will have 2 amps to compare side-by-side in January. Here is what he is referring to on V1 and V3.

V1:
150 Watts x 2 into 8 Ohms
300 Watts x 2 into 4 Ohms
600 Watts x 2 into 2 Ohms
Class A ~18 Watts

V2:
250 Watts x 2 into 8 Ohms
500 Watts x 2 into 4 Ohms
1000 Watts x 2 into 2 Ohms
Class A ~12 Watts

V3:
400 Watts x 2 into 8 Ohms
800 Watts x 2 into 4 Ohms
1600 Watts x 2 into 2 Ohms
Class A ~8 Watts

Below is an email I just sent to the guy that did my ROON Convolution filter for my small room system.

Since you are sound guy I thought you would find this interesting.

I was curious how the Benchmark AHB2 in mono would sound with my Thiel CS3.7, which likes power at low impedance. So I took my single stereo AHB2 and switched it to mono and drove only 1 speaker. It sounded louder and with more details. It also was much more hard hitting. I listened to Soundgarden: A Sides completely on stereo. I then kept everything the same and played the CD again but in AHB2 mono and single speaker. Even with a single speaker I had more bass. In fact the bass was so much that I had to change filters to the first one you gave me where the bass was not enhanced. After I changed from filter 3 to filter 1 my irritation subsided.

I was always curious whether more power at low to medium volume gives you better sound. For me it seems obvious that it does. I believe in mono the AHB2 gain is boosted 6 db however, I am hearing more than increased loudness. It is a better sound.

I should add that the AHB2 SNR drops to 135 when the AHB2 is run in mono. That is not much different that the SNR 132 in stereo but I was hearing more details in mono. I think my Thiel gobbled up that extra power and made better sound and it was not the SNR that made the sound better. 

 - Filter 1 was a Convolution file that was very flat. Now using with the single speaker running a AHB2 in mono (700 watts @ 2 Ohm)

 - Filter 3 was a Convolution file that had a slight bump in the bass from 100 Hz down. I was using this filter with the stereo AHB2 which does not have much power into 2 Ohm (259 watts).

So yes, I am buying a second AHB2 to run in mono. Maybe Floyd was using a more efficient speaker.

@diamonddupree Those numbers you listed was why I am still investigating more power. However, I really wanted make the AHB2 work because I like it more than other amps (I have heard a lot). For less than $3K I think I will improve my sound a lot by going mono. Even though the AHB2 is not officially rated at 2 Ohm because it cannot run a test tone for 30 minutes at 2 Ohm (the AHB2 in stereo can). I think that is inconsequential now after my test yesterday. Even if it clips the forward correction will stop that from getting to the speaker.

Since I have been investigating other amps. The 2 other lines I was considering are:

CODA #8

• 150 | 300 | 600 (approx. first 18 watt class A but halved as impedance halved)
• 250 | 500 | 1000 (approx. first 12 watt class A but halved as impedance halved)
  
• 400 | 800 | 1600 (approx. first 8 watt class A but halved as impedance halved)
  
• SNR 118

CODA #16 with a SNR 130 and first 100 watt Class A. I think it's power rating is as follows,  150 | 300 | 600.

The upcoming Class D Puriif amps with 1000+ watt in 2 Ohm. These ones maybe the closest sounding to the AHB2.

I was also considering the Luxman m900u which is similar in spec to the CODA #8 (150 | 300 | 600) but 3x the cost. It sounds great and the only one I have heard from this list.

I should be able to get a second AHB2 next month.

@diamonddupree I should be happy with the sound I am getting from a single AHB2 now. However, if I was that type of person I would not be hanging around A'gon.

I have great synergy with my all Benchmark system now. Adding that second AHB2 will just move the needle to 11.

@erik_squires When it comes to Convoluton filters what I have now was created by a rock star in the field, not by some random DIY’er who thinks they are an expert after tinkering around. This was done by a professional audio engineer doing this for 20+ years and has written a book on this issue.

What I have now is the best tweak or upgrade to my system. I do not know if you hang out in the Computer Audiophile site but my filters were created based on info posted there. Some very knowledge folks on this issue over there. I am posting my findings here because most folks on this site are not aware of the possibilities with Convolution.

My Convolution files was created using Audiolense which I understand is some very complicated software (Accurate is another option). It is also not free, like REW. I had to pay $200 for a 1 time license usage of the software by the outsourced audio expert. The implementation cost was another $500. Peanuts from my perspective. I paid more for an XLR interconnect and that had 0.00145% the benefit of the Convolution.

What I solved was getting a big speaker into a small room and getting it sounding perfect. That was my goal from the start and mission accomplished. It took me 2 years to get to this destination from the start of this thread.

https://forum.audiogon.com/discussions/big-speakers-in-small-room-at-moderate-volume-levels?highligh...

With regards to ROON setup, I have a 2 computer solution. My client computer was picked out of the trash 5 years ago from an previous employer. My ROON Core server is a under $1K DELL refurbished machine. It has something like 20 cores and 32 Gigs of RAM. This is actually my weakest server in the house, I have about 10 computers in the house. ROON Core does not need that much power, even with Convolution. If you go to the ROON forums and ask the ROON developers there they will tell you the same.

I had a buddy over to my office today. I had him sit at my desk and I played the music. He had the same reaction I am having, glorious sound. I have actually heard enough uber systems and other non-uber great systems to know that my system is now also great.