Bullet bitten and trigger pulled

[Feanor]

Tonight I did a little benchmarking with my current amp, the Class D Audio SDS-258. Understanding what I currently believe to be the strengths & weaknesses of this amp will help me understand the same for the new amp, the Pass Labs X150.5

To do this I am using my favorite reference recordings -- which include several Reference Records, (pun intended).

The SDS-258 actually has some great strengths -- remains to be seen if the new amp is better/equal/not so good:

• Very fine transparency, air, and separation of voices & instruments
• Very good soundstage and palpability of performers in it. The soundstage, to my ear, is just as wide, deep, and high as the recording provides -- as demonstrated by the ability of the amp to distinguish recordings from each other
• Lean, precise bass; not bloated or overhung (like my former NAD C270 or Forte Model 5)
• A clear, neutral mid-range the conveys instruments and vocals realistically, (unlike the Forte Model 5 that just sounded weird to my ear)

But there is definitely downside to the SDS:

• Highs that are extended but bright; not "grainy" or "etched" as those words are typically used, but definitely bright. On good recordings this isn't a big problem for me, but on less than good recordings highs can sound unpleasantly shrill.

[blackraven]

Bill, my X250 has more texture to the music when compared to my CDA-254. Both have good air and transparency but the Pass is more musical and detailed. I find treble to be pushed back with the Pass. It's my only complaint about it. I have not noticed any change in sound after the amp has been on for an hour but I have not been listening for it.

[Mr Peabody]

Blackraven what do you mean by "pushed back", is it further back in sound stage or are you saying rolled off? I find the treble very good in my system, I wonder if your effect is due to tube compliment of associated gear.

Bill, when you are noting the sound of the digital amp are you using the ARC preamp?

[Feanor]

Bill, when you are noting the sound of the digital amp are you using the ARC preamp?

Yes, my comments are based on driving the CDA SDS-258 with the ARC LS9 and a balanced connection.

However the general characteristics of the SDS were the same with the passive preamp I was using recently. The contribution of the LS9 is principally improved dynamics.

[Feanor]

Bill, my X250 has more texture to the music when compared to my CDA-254. Both have good air and transparency but the Pass is more musical and detailed. I find treble to be pushed back with the Pass. It's my only complaint about it. I have not noticed any change in sound after the amp has been on for an hour but I have not been listening for it.

Well the SDS-258 is a $600 amp while the 150.5 is $5,500 amp, so I will be ... uhmm ... "disappointed" if the latter isn't better in virtually all respects.

I won't miss the over-bright highs of the SDS provide the 'air' and overall naturalness are improved.

[blackraven]

Mr P. I find the treble to be pushed back in the sound stage and less prominent when compared to my A21 and Class D amps. There is also less air in the treble but there is also no grain. I have tried various tube combo's and some are better than others. I have 0.6 ohm resistors in my Maggie tweeters which I will remove this weekend which will help by increasing the tweeter volume by about 1dB.

Bill, your 150.5 will sound different than the X250. The 0.5 series has a different sonic character and is supposed to be more refined. When do you expect to receive the amp?

[Feanor]

...
Bill, your 150.5 will sound different than the X250. The 0.5 series has a different sonic character and is supposed to be more refined. When do you expect to receive the amp?

Maybe there are "refinements" but I believe they are relatively slight.

When will I get the 150.5? Well with any luck the seller will be able ship today. Due to the high shipping weight, 75 lbs, it can't be shipped USPS, (my preference by a wide measure), so it going FedEx.

FedEx was telling him he need a Certificate of Origin to export the amp. This CoO would make it possible avoid Canadian import duty under NAFTA. However the CoO requires official documentation from the manufacturer plus notarization.

I told my seller to tell FedEx that his buyer, (that's me), would pay the duty in the absence of an CoO. It's easier, quicker, and possibly cheaper to just pay the duty than obtain a CoO.

N.B. Under NAFTA in theory a US product can be imported in Canada without duty and vice versa. But in practice it doesn't work out so well in case of a one-off, personal cross-border sale -- see above. In fact, a US buyer can end up paying duty on a US-made product that he buys from a Canadian seller, (and vice versa): this sucks but it's the way it is. The good news is that the tariff rate is fairly low.

I HATE FedEx; I always prefer the USPS and Canada Post option for being far easier and often cheaper. Coming from the US to Canada it's invariably cheaper because Canada Post charges a flat brokerage fee which is only $8.00 depending on the service selected.

[frenchmon]

Well Fenor.....congrats! I'm sure your ears will like the Pass...its a great amp man. When I first heard Peabodys I loved it. And your talking about power concumption just sitting at 200 watts...try a wopping 270 watts my Vincent uses just sitting.

Harley, you took the words out of my mouth...the PASS LAB REVIEW FORUMS!

Jack...go ahead and get the Bryston.....I'm sure you will still be in the same category. Which model where you considering?

[Jack in Wilmington]

Well Fenor.....congrats! I'm sure your ears will like the Pass...its a great amp man. When I first heard Peabodys I loved it. And your talking about power concumption just sitting at 200 watts...try a wopping 270 watts my Vincent uses just sitting.

Harley, you took the words out of my mouth...the PASS LAB REVIEW FORUMS!

Jack...go ahead and get the Bryston.....I'm sure you will still be in the same category. Which model where you considering?

I was looking at the Bryston 4B-SST2 or the Pass X150.5

[blackraven]

Bill, when I talked to Reno Hifi, they guy tried to steer me into buying an X150.5 because he thought the 0.5 series sounded much better than the older X series. So I suspect that there is some truth to that from what I have read. I considered buying an x150.5 but I paid about $1K less for the X250. I was also looking at a used ARC amp, but Reno Hifi steered me away from it saying that he preferred the sound of the Pass amps.