Parasound & ATI amps

[crossedover]

The 3312 from denon at accesories4less @649 is hard to beat as a preamp. Not many pres with sub control of that level and price unless you go used. I'm using a BK ref 70 in a 2.1 office setup and have been considering this option. My other options for sub control include an electronic crossover and software ie REW

 

[PENG]

nor am I aware of ATI / Parasound claiming (or third party measurements showing) their products to be anything other than neutral. However, as jinjuku has mentioned, a tube amp would be one way to potentially gain a warmer sound.

As I said before, Parasound Halo power amp is neutral just like my other amps (Adcom, Anthem, Bryston, MarantzX2). I agee tube amps could be warmer, though as far as I know some of them are supposed to sound neutral as well under some conditions.

 

[PENG]

For "warmer" sound, I would get a pre-pro from Marantz or AVR from Denon (like the X4000) and let Audyssey XT32 help out here. I would go with the Audyssey Reference/default setting, which tapers down the treble. You may find the Audyssey Flat and Audyssey Bypass L/R too neutral since they do not taper off the treble.

That could be interestingly true, but purist would likely despise the use of any tone control and/or REQ.

Furthermore, Audyssey Dynamic EQ may also make the sound richer and fuller and less "thin", possibly less "neutral" and less "flat".

We know that for a fact right?

The main reasons I like ATI:
1) Big metal front handles - love the aesthetics of the front handles (McIntosh, Bryston, Vincent, ATI).
2) price
3) USA built
4) fuse-less protection circuit - no need to replace fuses. When I had my Acurus amps, I managed to blow a few fuses. So that burned into my mind. Don't want to mess with fuses.

To some people, e.g. Rich, Class A bias at low volume is a must. There is little reason why ATI, being class AB, would not have the inherit feature of running in class A at lower volume. It would likely be just a lower wattage level than equivalent Halo models. Since you know ATI well, would you mind asking them to confirm that and if yes up to how many watts?

Your point 1) about the big front handles, I tend to prefer front as well but not entirely sure yet. This weekend I am going to swap out the Halo with the Bryston so I should be able to stack one on top of the other and take a picture.

 

[RichB]

To some people, e.g. Rich, Class A bias at low volume is a must. There is little reason why ATI, being class AB, would not have the inherit feature of running in class A at lower volume. It would likely be a matter maybe to a lower wattage level than equivalent Halo. Since you know ATI well, would you mind asking them to confirm that and if yes up to how many watts?
.

I tried to determine ATI's class-a bias but never managed to do so.
But, the ATI3005 and idled at 145 watts (as I recall) and the A51 idles at 150 watts, if that's any indication.

- Rich

 

[PENG]

I tried to determine ATI's class-a bias but never managed to do so.
But, the ATI3005 and idled at 145 watts (as I recall) and the A51 idles at 150 watts, if that's any indication.

- Rich

That could be a reasonable indication since both are class AB design but I don't think it would be an accurate one due to other factors. It probably should get you in the ball park though. My Bryston's consumption is 170W at idle but I was told it outputs 20 to 25W (class A) when the bias level is reached.

I am quite sure ADTG can get an answer from ATI if he tries.

 

[RichB]

That could be a reasonable indication since both are class AB design but I don't think it would be an accurate one due to other factors. It probably should get you in the ball park though. My Bryston's consumption is 170W at idle but I was told it outputs 20 to 25W (class A) when the bias level is reached.

I am quite sure ADTG can get an answer from ATI if he tries.

I found my notes and the ATI3005 idled at 130 watts, so it is still in the ball-park.

The Parasound A21 idles at 150 watts as well. Parasound amps use a higher bias when powered on cold and then work their way down as they warm up. The A51 and A21 cold start in the low 200 watt range.

- Rich

 

[AcuDefTechGuy]

That could be a reasonable indication since both are class AB design but I don't think it would be an accurate one due to other factors. It probably should get you in the ball park though. My Bryston's consumption is 170W at idle but I was told it outputs 20 to 25W (class A) when the bias level is reached.

I am quite sure ADTG can get an answer from ATI if he tries.

Well, I may have connection with sales (and drugs) , but real technical engineering questions may best be pursued by real professional electrical engineers.

 

[AcuDefTechGuy]

Pre-Amp... I still haven't ruled out the Denon AVR that you had suggested in another thread.. Although this is just a simple 2.1 system. I will be honest. I would like to keep it to two channel vs AVR... By the way I am also in the process of treating the room a little bit. I know this will tone down the room a little.

See, the "problem" with high quality stereo preamps and amps is that their frequency responses are all from 20Hz-20kHz +/- 0.1dB, which is as cold, clinical, sterile, flat, and neutral as you can get.

To get that "warm" sound, you need the frequencies above 8kHz to be @ about -3dB, not -0.1dB.

Room treatments may help a little, but you will really need help from Audyssey or some other EQ software.

 

[Irvrobinson]

I'm not sure I'd recommend buying an amplifier to act as a tone control, nor am I aware of ATI / Parasound claiming (or third party measurements showing) their products to be anything other than neutral. However, as jinjuku has mentioned, a tube amp would be one way to potentially gain a warmer sound. Other than his suggestion of NAD, one other possibility I'd throw out there is Audio by Van Alstine; he demoed gear at CAF with Philharmonic & Salk, and mentioned that he aimed for a "tube sound" for some of his solid state gear (and there are a few subjective reviews float around that seem to corroborate the story) that might be up your alley.

avahifi - avahifi

That's actually a worrisome thought, that someone would "voice" electronics. As for tube amplifiers, I haven't noticed that properly-designed tube amp sound different in an obvious way. They just cost more and dissipate more power per output watt.

 

[jinjuku]

That's actually a worrisome thought, that someone would "voice" electronics. As for tube amplifiers, I haven't noticed that properly-designed tube amp sound different in an obvious way. They just cost more and dissipate more power per output watt.

Some times the best way to help the patient is prescribe a placebo, help a little bit by being positive via affirming their 'results', and letting them and everyone else move on.

 

[RichB]

Some times the best way to help the patient is prescribe a placebo, help a little bit by being positive via affirming their 'results', and letting them and everyone else move on.

In that case, take two class-A's and call me in the morning; They last longer than tubes.

- Rich

 

[ematthews]

Fully balanced ATI looks like a winner. I've been speaking with Jeff at ATI the last few days and for the price it seems great. I haven't decided by any means but ATI is now a front runner.
So many options.... I'm taking my time this go around.
And yes, I understand that these SS amps will be neutral.

 

[slipperybidness]

I tried to determine ATI's class-a bias but never managed to do so.
But, the ATI3005 and idled at 145 watts (as I recall) and the A51 idles at 150 watts, if that's any indication.

- Rich

I'm not certain what you are trying to get at here???

When you talk about bias, you are talking about how much Voltage is applied to the base of the transistors, not Watts.

Class A bias is "mid-point" bias, meaning that the transistor is half-way between cutoff and saturation. It is the most linear bias technique and introduces the least amount of distortion, but it wastes the most power (class A is only about 25% efficient AT BEST). The "Power at Idle" that you mention is technically called "Quiescent Power" and is found by multiplying current times voltage.

For class B, the bias is "@ cutoff" and for class AB the bias is "just above cutoff". Class B or AB can get efficiency in the 75% range AT BEST.

 

[RichB]

I'm not certain what you are trying to get at here???

When you talk about bias, you are talking about how much Voltage is applied to the base of the transistors, not Watts.

Class A bias is "mid-point" bias, meaning that the transistor is half-way between cutoff and saturation. It is the most linear bias technique and introduces the least amount of distortion, but it wastes the most power (class A is only about 25% efficient AT BEST). The "Power at Idle" that you mention is technically called "Quiescent Power" and is found by multiplying current times voltage.

For class B, the bias is "@ cutoff" and for class AB the bias is "just above cutoff". Class B or AB can get efficiency in the 75% range AT BEST.

I was referring to the Parasound Feature description of their Halo amps as "High bias class A/AB operation".
The Parasound A51 runs Class-A for the first 8 watts (according the Richard Schram) and idles at about 150 watts after warm-up.

The ATI3005 ran about 130 watts at idle, but I have no idea if it has this feature. I was hoping someone more knowledgeable would jump in

- Rich

 

[RichB]

Fully balanced ATI looks like a winner. I've been speaking with Jeff at ATI the last few days and for the price it seems great. I haven't decided by any means but ATI is now a front runner.
So many options.... I'm taking my time this go around.
And yes, I understand that these SS amps will be neutral.

Are you going for the ATI3000 series?

One nice thing, is that you can add more channels if you need more. If that is something you are considering, you can ask Jeff about pricing.

- Rich

 

[AcuDefTechGuy]

Are you going for the ATI3000 series?

One nice thing, is that you can add more channels if you need more. If that is something you are considering, you can ask Jeff about pricing.

- Rich

It seems like the important thing here is the return policy.

What is ATI's return policy?

 

[ematthews]

It seems like the important thing here is the return policy.

What is ATI's return policy?

Ha.... I have only returned one thing in my audio purchase history believe it or not...

ATI2000 series is what I am looking at.. No need to add later on as all I do is 2 channel.

 

[RichB]

It seems like the important thing here is the return policy.

What is ATI's return policy?

Pretty good.

- Rich

 

[slipperybidness]

I was referring to the Parasound Feature description of their Halo amps as "High bias class A/AB operation".
The Parasound A51 runs Class-A for the first 8 watts (according the Richard Schram) and idles at about 150 watts after warm-up.

The ATI3005 ran about 130 watts at idle, but I have no idea if it has this feature. I was hoping someone more knowledgeable would jump in

- Rich

OK.

Sounds to me that "high bias class A/AB" means that they are biased higher than a normal class AB design. As I said previously, Class AB is biased "just above cutoff", so I'm guessing that they are saying it is biased "well above cutoff", approaching class A or midpoint bias.

 

[AcuDefTechGuy]

Ha.... I have only returned one thing in my audio purchase history believe it or not...

ATI2000 series is what I am looking at.. No need to add later on as all I do is 2 channel.

A brand new ATI AT2002 sounds pretty good.