You are correct! The question is...why is the back of the amp labelled the reverse of virtually all other HIFI equipment? I plan on contacting Coda tomorrow to ask about this and why the input impedance is so low. ; )
The new Coda S5.5 amplifier: It's a "Petite Beast"!
I have in-house the New Coda Technologies S5.5 amplifier for review for Stereo Times website. It will be awhile before I write the review. However, I'm so impressed by the performance of this petite amplifier, it only weights 45 pounds, that I wanted to give a heads up to you GON members if you are in the market for a balanced pure class A amplifier, delivers 50 watts @ 8 Ohms, and can drop 100 Amperes of current on a peak!
The world class build quality of Coda amplifiers is on display with the S5.5, along with the most beautiful purity of tonality, precise sound-staging, complete liquidity offered by pure class A design, and what might be the best top end regarding details, decays, and a natural shimmering without brightness or any edge at all.
The S5.5 uses extremely wide bandwidth output transistors instead of the usual TO3 devices used in most transistor designs. I own the Coda #16, which is great, but the midrange/high end is taken to another level of musical enjoyment with the S5.5. The S5.5 has a sense of speed/aliveness that is exciting to listen to that you experience in live music. The amp is dynamic as hell, has driven with ease any speaker I have tried it with, hence my nickname of the "Petite Beast". Remember, 50 watts pure class A, can drop 100 amperes of current and only weights 45 pounds.
Teajay (Terry London)
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Here is Doug Dales response to me about the S5.5 amp wattage rating. I think this will clear things up! Mark
“The amp is smallest in production. It does double into 4 and again into 2 but at 2 Ohms there may be current limiting on transients and it is not optimal. Below 2 Ohms is not advised. Unlike power the Class A region shrinks as you lower load impedance. The comment about 40 at 4 Ohms is likely a reference to the Class A wattage.”
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Does this sound like a correct interpretation based on your recent post and my discussion with Doug. In a sense the S5.5 is a 50 WPC at 8ohm Class AB amp (it may be even slightly higher) except the first 50 watts are Class A; so it's a genuine 50WPC Class A amp for 8 ohm impedance. I am saying this because of how the No. 16 amp is rated in the manual as follows "150 WPC Class AB at 8 ohm (first 100 watts are Class A". For the S5.5, the doubling to 100WPC at 4 ohm and 200WPC at 2 ohm is not Class A but rather Class AB. None of these power specs matter much though because what does matter is how well the amp is producing phenomenal audio. For the S5.5, at 4 ohm impedance the Class A WPC rating would therefore indeed be less than 50WPC (40 WPC Class A is reasonable) and at 2 ohm's even less wpc for the given output voltage of the amplifier. Again, the power ratings don't really matter. The S5.5 manual states only the key spec (50 watts into 8 ohm Class A). The sound the amp produces is what matters. The S5.5 is certainly looking like a phenomenal Class A amp and a true great value. |
Color me confused? I have never had a class a amp. I had the Parasound A21+ which was class A up to a certain point and then switched to AB. But if I was going to buy a class A amp and was interested in its power rating (not including current) would I want to know (?): Watts at 8, 4 and 2 ohms class A As well as: Watts at 8, 4 and 2 ohms class AB |
@aolmrd1241 Thanks for that! Very helpful. |
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