Need an amp for low ohm speakers

[boXem]

I just read the spec sheets. No special sauce.

There is no such data in the TPA3255 spec sheet for a very simple reason: TPA3255 outputs are not directly connected to the outside world.
And there is another very simple reason for you not bringing the data.

 

[AcousticTheory]

There is no such data in the TPA3255 spec sheet for a very simple reason: TPA3255 outputs are not directly connected to the outside world.
And there is another very simple reason for you not bringing the data.

ICEPower 200AS2 (TPA3255): DF = 30 below 100 Hz at 4 ohms per that module's spec sheet. Somebody else is providing this data.

NC252MP = >300 at 4 ohms has been measured (Archimago), and Samsa on this forum estimated damping factor of about 700 based on 2.5 feet of 12AWG.

So it was someone else's spec sheet, but it's a spec sheet for an implementation that is not known to be broken.

Whether that is the exclusive reason for the minor difference in bass character I noticed when switching between these families of amps (I have 200AS2, 300AS1, NC122MP, and NCx500) on the same speaker is open for discussion. True to form, someone will roll up and claim my observation to be of no value because it is subjective and sighted. That's fine; it is what it is.

 

[pma]

NC252MP into 2 ohm :

Link

 

[boXem]

ICEPower 200AS2 (TPA3255): DF = 30 below 100 Hz at 4 ohms per that module's spec sheet. Somebody else is providing this data.

NC252MP = >300 at 4 ohms has been measured (Archimago), and Samsa on this forum estimated damping factor of about 700 based on 2.5 feet of 12AWG.

So it was someone else's spec sheet, but it's a spec sheet for an implementation that is not known to be broken.

Whether that is the exclusive reason for the minor difference in bass character I noticed when switching between these families of amps (I have 200AS2, 300AS1, NC122MP, and NCx500) on the same speaker is open for discussion. True to form, someone will roll up and claim my observation to be of no value because it is subjective and sighted. That's fine; it is what it is.

In you initial message I read (and reacted to) lower output impedance while you wrote lower damping factor. My bad, sorry for the trouble.

 

[wadude]

I ended up getting the Purifi stereo amp from Buckeye. It should be here in a few weeks. Thinking about getting the Schiit Sega 2 for the preamp.

I absolutely loved my Dynaco rig and have a deep respect for vintage collecting. Ditching the PAS2 for passive attenuation was the first step to hearing what a pair of MKIVs can do. This ultimately led to replacing those amps with a Buckeye 252. I will never look back. Modern speakers are on the horizon but I need to do a lot of listening before settling on a pair.

 

[Ted G]

Thanks everyone, update- I purchased the purifi version of the Buckeye amp to power the speakers. It doesn’t even get hot when I crank it. I paired with the WiiM Ultra and connected to my old cd player via the optical output to get the benefit of a newer DAC. For the separate Pioneer receiver system I’m still able to utilize the RCA-outputs to play through a separate pair of 8 ohm speakers.

 

[mhardy6647]

Jeepers -- an SX-1980.

 

[Zinda]

Hello,

Fulfilling my teenage dreams, I purchased a Pioneer SX 1280 receiver. Unfortunately, even with 200 watts per channel it can't run the recently acquired pair of Infinity RS-2.5 speakers at high volume for very long before cutting out on protection. After doing some research, I found that the speakers can run down under 3 ohms when the bass kicks in and the receiver can't handle it. I'm considering getting a purifi or hypex based class D amp. The alternative is a used Adcom 555 or similar. I'd love a beefy Mcintosh but I've already dropped a lot on what I have . Also, rather than using the receiver, what is an inexpensive alternative pre-amp? I am not a purist as you can tell with the Bose 901's. Please hifi guru's lend your expertise!

View attachment 463229

Imagine that, the amp that's held as the holy grail for vintage pioneer gear will be replaced by a cheap digital amp because the huge amp can't handle 3 ohm loads! This cracks me up, it also makes a huge statement in the reasoning for the old Pioneer gears pricing being seen. I wonder how many old expensive amps are actually seeing full time use with high quality speakers.

There are some really nice fanless power amps out there made by big name companies that put out huge power with high damping factors for cheap, you just need to wait for some good ones to come up for sale. I'm not going to get into models because there's so many, the one thing to consider is they may have been used in live sound setups and taken abuse and repairs may have been made along the way. Checking the inside is always important to spot any poor repairs.

I would def look into some older convection cooled amps with 2 or even 1 ohm ratings to drive those speakers into a usable range with authority, they're not made for light weight amps , high current, high damping will do best to bring out all those speakers can do. The difference will amaze you, just the power and control over the woofers alone will be very noticable with a high current amp.