2. amps-preamps
  3. 125665-369

What makes an amp sound more direct ?

In our hifi journey we have probably all heard amps with different topologies and implementation. Most of these amps would have an implementation which is a combination of one of these:

1. Single Ended
2. Push-pull
3. Balanced
4. Differentially Balanced
5. Class A, A/B, D
6. High/Low Damping factor
7. Zero Negative Feedback (global & local)
8. Low/Medium/High Negative feedback
9. 2/3/4/multiple gain stages

There will be more such items that can be added to the list. My curiosity arises from the fact that some amplifiers (or even preamplifiers) sound much more direct than others. The ones that does this trick generally seems to do the "they are here" trick very well. While the components which sound relatively indirect cast a sound scape which gives the perspective of "we are there".

Just from my observation, single ended and zero feedback designs sound much more direct than balanced designs especially ones with high negative feedback. Is this a coincidence or is there a valid reason behind this ? 
pani
larryi
4,133 posts
 

I agree that zero feedback and single-ended are quite direct sounding.  But, some of the most direct, immediate and vibrant sound can be had from output transformerless tube amps. 

This would be a rough generalization because I've heard some extremely direct sounding push-pull amps too.  Among the very best amps I've heard are the Western Electric 59A (crazy rare and expensive-pushpull), a recently built one-of-a-kind 271a amp (indirectly heated triode-pushpull), and a one-of-a-kind output transformerless amp. 

I own two amps that are not too bad in terms of delivering an immediate and vibrant sound: 1) a modern build of a Western Electric 133a (using vintage parts, including authentic WE input and output transformers and plate-type resistors); and an Audio Note (uk) Kageki (parallel single-ended).

jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
I'm not sure what you mean by "direct" sounding, could you elaborate?

Are you talking about how some amps present a more immediate (forward) sound-stage, while other amps present a more laid back, deeper, sound-stage?
Some make you feel like you are mid-hall, while others make you feel like you are in the front row?
Or are you thinking of something else entirely?
czarivey
5,946 posts
 
10. Speakers.
pani OP
1,219 posts
 
jmcgrogan2, it is not exactly a soundstage phenomenon per se. Immediacy...yes. Direct sound is a bit self-explanatory already, the way the sound is directed to the listener. The listener actually feels a touchy-feely with the instruments in the room as if they are being played "for him". Even if the stage is behind the speaker, the way the notes are formed is like looking through a lens whose focus on the objects are spot-on. Sometimes it becomes difficult explain these phenomena even though it is ubiquitous.

Larryi, I had a couple of 300B SETs at home and also the famous Tenor Audio OTL 75 amp (its a push-pull). It was very clear that the Tenor did not have the directness of the SETs but it was clearly faster with wider bandwidth. Interestingly Naim amplifiers have a very direct sound though not in the same league SETs, still...
Similarly the Nelson Pass Firstwatt amps also sound more direct than most of the other typical SS amps including the Pass XA.8 amps.

Recently I heard some SS amps which were very well built, with very high damping factor. Even though they were tonally nice (not SS dry) they clearly sounded "indirect". 
unsound
7,336 posts
 
IME, this directness you speak of usually has more to do with the recording technique than anything else.
More to discover