megabigeye
Headphoneus Supremus
Actually, I believe the Crack's output impedance is closer to 120Ω, as measured by Tyll at InnerFidelity. I regard the 8:1 damping factor to be a rule of thumb rather than law.
As explained to me by some with more knowledge than I, dynamic drivers don't have a flat impedance like planar drivers so how a amp "see" it as the impedance of the driver varies with frequency is what "synergy" is being talked about IIRC. And I've been told that there is also a possibility of over damping a driver and like @megabigeye noted the 1/8 ratio is a rule of thumb and not a hard and fast rule. Another thing about "synergy" is over the years I've found that some pairings of amp and headphone just seem to work better than others, the effect of an amps output impedance can have quite an effect on the sound, to me there is no good or bad most of the time, just differences/preferences and I've found that I have a lot more to learn in this crazy hobby and having a SO that understands this and even shares the passion for good/great audio is as good as it gets. I hope another can chime in on what "synergy" is since I know my explanation is only my thoughts and other may have a much better way of saying/explaining it.Your statments raises some questions. What is the 75 ohms doing? 75 ohms is 25% of 300 ohms, and general rule of thumb is less than of equal to 12.5% of total ohmage.
Another question is what specifically is synergy? It is a vague term that doesn't explain.
What is actually going on?
Does my 2 ohm output impedance solid-state sound worse or more proper?
The BH Crack's output impedance is dependent on the power/output tube used, and IIRC the stock 6080 is rated around 120ohms. My choice of power tubes are TS5998 or WE421A which are known for having lower output impedance of 70-75ohm I'm told by those on the BH Crack thread and there are some tubes that have even higher output impedance than 120ohms so this could be why some say the BH Crack is really good while others say its just okay. WARNING: tube rolling is a very deep rabbit hole but is quite fun. I think the cost of the tubes I have makes the cost of the BH Crack kit the cheap part of the investment by a 4 to 1 margin by my estimates. One nice point is that my Ember uses the same tubes as my BH Crack for drivers and can also share tubes with my Lyr2Actually, I believe the Crack's output impedance is closer to 120Ω, as measured by Tyll at InnerFidelity. I regard the 8:1 damping factor to be a rule of thumb rather than law.
Yes.Please indulge the electrically/electronically impaired for a moment...this 1 to 8 ratio: does it suggest that optimum impedance match is an amp w/an output impedance 1/8th the impedance of the headphone?
Similarly, my mom can't decide if she loves me most because I was the first boy, or if she loves her grandson the most because he's the youngest boy. (<-- because there's no really ironic looking smiley)After all these years, I still can't decide if I like my HD650 more, or my Q701 (with a bass boost) more. I plan to continue to own both, but I can't decide which I like better.
After all these years, I still can't decide if I like my HD650 more, or my Q701 (with a bass boost) more. I plan to continue to own both, but I can't decide which I like better.
Run them both at the same time and put one HD650 earcup on left ear and Q701 on right ear.
Please indulge the electrically/electronically impaired for a moment...this 1 to 8 ratio: does it suggest that optimum impedance match is an amp w/an output impedance 1/8th the impedance of the headphone?
Interestingly enough, I can't find an output impedance spec for my Woo WA3 (the only OTL/higher output impedance amp I have).
the "at least" 1/8 rule of thumb is like a crossroad where various ideas can coexist pretty well:Please indulge the electrically/electronically impaired for a moment...this 1 to 8 ratio: does it suggest that optimum impedance match is an amp w/an output impedance 1/8th the impedance of the headphone?
Interestingly enough, I can't find an output impedance spec for my Woo WA3 (the only OTL/higher output impedance amp I have).