STA-9

Armaegis · « **Reply #80 on:** 14 May 2016, 08:54 pm »

Quote from: Eisener Bart on 14 May 2016, 11:57 am

Yeah, you are right. I meant enough current.

My Speakers are Audio Physic Avanti.

The current should be inconsequential. Any amp input impedance should be very high; even if you had a dozen of them chained together, you're still in the milliamp range.

I think the benefits of bi-amping here are going to be squashed because you're ultimately driving the crossovers, not the speakers. As Jason mentioned, you'd probably be better off running a bridged amp in mono (for higher quality power, rather than simply "more") on each side and don't fuss with the bi-amping.

In my opinion, to truly benefit from bi-amping in the way that you're thinking, you will want to bypass the internal crossover entirely. This requires an active crossover setup, which comes *before* the amps. I do this regularly with my PA setups using a Behringer DCX2496.

restrav · « **Reply #81 on:** 14 May 2016, 09:15 pm »

so if

Quote from: Armaegis on 14 May 2016, 08:54 pm

The current should be inconsequential. Any amp input impedance should be very high; even if you had a dozen of them chained together, you're still in the milliamp range.

I think the benefits of bi-amping here are going to be squashed because you're ultimately driving the crossovers, not the speakers. As Jason mentioned, you'd probably be better off running a bridged amp in mono (for higher quality power, rather than simply "more") on each side and don't fuss with the bi-amping.

In my opinion, to truly benefit from bi-amping in the way that you're thinking, you will want to bypass the internal crossover entirely. This requires an active crossover setup, which comes *before* the amps. I do this regularly with my PA setups using a Behringer DCX2496.

so if someone has a computer as the source and the a DAC directly driving the amp, then where would this activecrossover go? I imagine you are talking about a solution like miniDSP? then it would have to go before the DAC, right?

and if so then you need 3 DACs for the 3 way system? im probably missing something

Armaegis · « **Reply #82 on:** 14 May 2016, 10:04 pm »

If you use a miniDSP and output separate digital signals, then yes you would need dacs downstream of each.

My use of the word "active" above was a bit of a flub; you could still use a passive crossover after the dac to split the stream, and you would feed these new channels directly to your amps.

In my case, my DCX2496 performs both crossover and DAC duties. Actually, when I feed it two analog channels from a mixer: it does the ADC conversion first, handles all the hoopla digitally, then does DAC duties again and spits out 6 channels.

rustydoglim · « **Reply #83 on:** 15 May 2016, 08:11 am »

The direct driving of speaker drivers is an expensive solution and also depending on the components to output band limiting frequencies (high freq to tweeter, mid and low to woofer if it is two way). A well designed cross-over can do a good job so I think before anyone make such attempt, you should review the FR plot of your speaker.

maty · « **Reply #84 on:** 15 May 2016, 09:13 am »

-> http://www.audionet.com.tw/a/thread-8356-1-1.html

maty · « **Reply #85 on:** 15 May 2016, 09:16 am »

-> http://www.feversound1.com/nuprime-ida8/

Nidri17 · « **Reply #86 on:** 15 May 2016, 09:36 am »

Wonder why the board inside the STA-9 has writing that says 'IDA-8'?
Is the amp module the same?

rustydoglim · « **Reply #87 on:** 15 May 2016, 03:37 pm »

The power stage board is the same but the "preamp" stage is different. The preamp stage in STA-9 makes it "tube-like" sounding.
See the illustrative diagram on the product pages for STA-9 and IDA-8.
As I have said, we are an engineering company, what you see is what you get

maty · « **Reply #88 on:** 15 May 2016, 04:10 pm »

The STA-9 toroid is bigger.

And the BIG capacitors are... 105 ºC, surprising in this price range, which speaks highly of the manufacturer.

Eric Gustafsson · « **Reply #89 on:** 26 May 2016, 06:30 am »

STA-9 used as monoblocks is a giant killer. I've never heard a better amp regardless of price.

hk29 · « **Reply #90 on:** 27 May 2016, 02:10 am »

Quote from: Eric Gustafsson on 26 May 2016, 06:30 am

STA-9 used as monoblocks is a giant killer. I've never heard a better amp regardless of price.

Oh don't tell me that!

I'm deciding between the ST-10 vs. STA-9 monoblocks. I wish there was a store I could listen to them. Its a tough decision based on reading it. From what I've read: STA-9 Mono (warm, dynamic) vs. ST-10 (resolution). Its a tough trade-off for me....

Does bridging the STA-9 change the sound quality in any way (besides higher power)?

larsg · « **Reply #91 on:** 27 May 2016, 06:09 am »

Switched between 2 STA-9 and ST-10 for some weeks now, 3 days STA-9 3 days ST-10 ++
ST-10 got that little extra for me.

Eric Gustafsson · « **Reply #92 on:** 27 May 2016, 11:13 am »

I discovered Yesterday that STA-9 needs a realy good preamp to perform at top.
My passive preamp from Hattor Audio makes STA-9 become a star.

rustydoglim · « **Reply #93 on:** 28 May 2016, 09:09 pm »

The HPA-9 is a very good preamp for STA-9 if you don't want to use a DAC as preamp.

Eisener Bart · « **Reply #94 on:** 16 Jun 2016, 08:32 pm »

I will get STA-9 for testing tomorrow.

Nidri17 · « **Reply #95 on:** 16 Jun 2016, 08:42 pm »

Quote from: larsg on 27 May 2016, 06:09 am

Switched between 2 STA-9 and ST-10 for some weeks now, 3 days STA-9 3 days ST-10 ++
ST-10 got that little extra for me.

I have the ST-10 (and DAC-9) and I'm very happy with the sound.
But I'm very curious about the 'warmth' of the STA-9 that a lot of people refer to.
Like I said, I'm happy, but I could be even happier perhaps?

rustydoglim · « **Reply #96 on:** 16 Jun 2016, 10:57 pm »

See the Amp Comparison chart. You have the ST-10 and going with STA-9, you will give up something on the ST-10

Eisener Bart · « **Reply #97 on:** 17 Jun 2016, 05:41 pm »

Well.

rustydoglim · « **Reply #98 on:** 17 Jun 2016, 06:08 pm »

You are not using our original feet

Eisener Bart · « **Reply #99 on:** 17 Jun 2016, 06:14 pm »

Quote from: rustydoglim on 17 Jun 2016, 06:08 pm

You are not using our original feet

I am using my own production. And I can bet that it's better.