First Watt or XA series

[Dave_A]

I'm trying to decide between the F4 (First Watt) (2 for mono operation) and the XA160.5s. My JBLs (S4700s) are 94db efficient so I take it First Watt will work?

So, which sounds better in your opinions? First Watt amps are a lot less money than the Pass Labs XA series, and I'm better to afford them really...

Your thoughts? Thanks in advance.

 

[LL21]

Hi Dave_A,

Cannot speak for your particular speakers, but some thoughts come to mind:

1. What is the impedance load of your speaker? If reasonably benign, that helps. a sub-1ohm load at 94 db is different (particularly for tubes) than an 8ohm load.
2. Depending #1 above, you then need to consider if First Watt can drive the speaker given its impedance load
3. In general, if #1 is a benign load, First Watt could do it depending on your listening levels and kind of music

I drive 95db speakers with benign 6ohm load with only 2 dips to 3ohms at 80hz and 17hz...probably rarely get much past first few watts, crescendos aside. But I do listen to deep house electronic and orchestral including Hans Zimmer soundtracks which can be taxing. I use 160-watt/channel dual-mono Class A amp...and I can tell the difference between setting the Bias switch to High Bias (full Class A at 160 watts) and Low Bias (only first 16 watts? are class A). Medium Bias (32-50? watts Class A) is much harder to tell the difference.

 

[Dave_A]

Hi Dave_A,

Cannot speak for your particular speakers, but some thoughts come to mind:

1. What is the impedance load of your speaker? If reasonably benign, that helps. a sub-1ohm load at 94 db is different (particularly for tubes) than an 8ohm load.
2. Depending #1 above, you then need to consider if First Watt can drive the speaker given its impedance load
3. In general, if #1 is a benign load, First Watt could do it depending on your listening levels and kind of music

I drive 95db speakers with benign 6ohm load with only 2 dips to 3ohms at 80hz and 17hz...probably rarely get much past first few watts, crescendos aside. But I do listen to deep house electronic and orchestral including Hans Zimmer soundtracks which can be taxing. I use 160-watt/channel dual-mono Class A amp...and I can tell the difference between setting the Bias switch to High Bias (full Class A at 160 watts) and Low Bias (only first 16 watts? are class A). Medium Bias (32-50? watts Class A) is much harder to tell the difference.

1. Impedance is 6 Ohms. Not sure what it dips down to.

2. I see. Not sure exactly. I'll find out.

3. I listen fairly loud, basically all genres of music.

I see. For that kind of music, which bias is better suited for it?

Thanks for your comments.

 

[PeterA]

I'm trying to decide between the F4 (First Watt) (2 for mono operation) and the XA160.5s. My JBLs (S4700s) are 94db efficient so I take it First Watt will work?

So, which sounds better in your opinions? First Watt amps are a lot less money than the Pass Labs XA series, and I'm better to afford them really...

Your thoughts? Thanks in advance.

This is a perfect question for Mark Sammut at Reno HiFi or for the folks at Pass Labs. Just give them a call and ask the question.

 

[Dave_A]

This is a perfect question for Mark Sammut at Reno HiFi or for the folks at Pass Labs. Just give them a call and ask the question.

Ok, thanks, I appreciate the suggestion. I will do that soon...

 

[LL21]

1. Impedance is 6 Ohms. Not sure what it dips down to.

2. I see. Not sure exactly. I'll find out.

3. I listen fairly loud, basically all genres of music.

I see. For that kind of music, which bias is better suited for it?

Thanks for your comments.

I would not be surprised if first watt would drive it well...though as with all things, it is a matter for your priorities. If you are a bass freak seeking unflappable bass at high volumes, you may choose power, whereas if you seek the ultimate in SET like magic...you probably get good bass with first watt and your speakers...and may prefer being seduced by its midrange.

Purely a guess but both probably work well...and it comes down to choice. My choice was that I like being seduced by mids, but Not at the expense of unflappable bass and endless power. I ended up spending over a year searching for high powered tubes...and came across Gryphon, and am very happy.

 

[Dave_A]

I would not be surprised if first watt would drive it well...though as with all things, it is a matter for your priorities. If you are a bass freak seeking unflappable bass at high volumes, you may choose power, whereas if you seek the ultimate in SET like magic...you probably get good bass with first watt and your speakers...and may prefer being seduced by its midrange.

Purely a guess but both probably work well...and it comes down to choice. My choice was that I like being seduced by mids, but Not at the expense of unflappable bass and endless power. I ended up spending over a year searching for high powered tubes...and came across Gryphon, and am very happy.

Yeah, I understand. I'm not a bass freak, per se. But I do like good, powerful bass. Basically, I wanted a Class A amp that's got all of the magic and not too tough on price. That's why First Watt came to mind. We're talking around $5000 for a pair of F4s to run them as balanced XLR bridged monos (100 Wpc into 8 Ohms) vs. $22000 for a pair of XA160.5s. Plus, the First Watt's are built by Nelson himself. I'm already looking to get the XP-25 phono preamp, and that's around $10000. I'm looking at the older X1 preamp as Nelson Pass says in the owners manual (I've been reading that quite a bit) that that will drive the F4s. I imagine the newer XP preamps will as well, but those are a bit too pricey since I really want that XP-25. Also, from what I've read on the First Watt site is that the bridged monos would in fact have enough power, but see for yourself...(read the manual too)

http://www.firstwatt.com/f4.html

 

[PeterA]

Yeah, I understand. I'm not a bass freak, per se. But I do like good, powerful bass. Basically, I wanted a Class A amp that's got all of the magic and not too tough on price. That's why First Watt came to mind. We're talking around $5000 for a pair of F4s to run them as balanced XLR bridged monos (100 Wpc into 8 Ohms) vs. $22000 for a pair of XA160.5s. Plus, the First Watt's are built by Nelson himself. I'm already looking to get the XP-25 phono preamp, and that's around $10000. I'm looking at the older X1 preamp as Nelson Pass says in the owners manual (I've been reading that quite a bit) that that will drive the F4s. I imagine the newer XP preamps will as well, but those are a bit too pricey since I really want that XP-25. Also, from what I've read on the First Watt site is that the bridged monos would in fact have enough power, but see for yourself...(read the manual too)

http://www.firstwatt.com/f4.html

You may want to think about an XP10 and XP15 versus an X-1 and XP25. The F4 is certainly less expensive than the 160.5 and may be great with your speakers. But, you could also consider a used XA100.5 for roughly $10K, much less than $22K. Reno HiFi may have some of these as demo units and he is a wealth of information, so Mark could advice you and also may save you some money. It sounds like you are going to have a great sounding system.

 

[Dave_A]

You may want to think about an XP10 and XP15 versus an X-1 and XP25. The F4 is certainly less expensive than the 160.5 and may be great with your speakers. But, you could also consider a used XA100.5 for roughly $10K, much less than $22K. Reno HiFi may have some of these as demo units and he is a wealth of information, so Mark could advice you and also may save you some money. It sounds like you are going to have a great sounding system.

I talked to Desmond at Pass Labs, and he said the X1 and XP10 are equivalent for the most part...

XP15? Maybe...it is less money than the XP25. I'll look more into it...

Right, that's what I was thinking...$10K is more than I'd like to spend on amps.

Ok, I'll check Reno Hi-Fi.

Yeah, I hope so! Your system looks great too!

 

[LL21]

Yeah, I understand. I'm not a bass freak, per se. But I do like good, powerful bass. Basically, I wanted a Class A amp that's got all of the magic and not too tough on price. That's why First Watt came to mind. We're talking around $5000 for a pair of F4s to run them as balanced XLR bridged monos (100 Wpc into 8 Ohms) vs. $22000 for a pair of XA160.5s. Plus, the First Watt's are built by Nelson himself. I'm already looking to get the XP-25 phono preamp, and that's around $10000. I'm looking at the older X1 preamp as Nelson Pass says in the owners manual (I've been reading that quite a bit) that that will drive the F4s. I imagine the newer XP preamps will as well, but those are a bit too pricey since I really want that XP-25. Also, from what I've read on the First Watt site is that the bridged monos would in fact have enough power, but see for yourself...(read the manual too)

http://www.firstwatt.com/f4.html

They're old, but the Forte 4 was a tremendous Class A 50 watt/channel amp which you could combine with a 2nd...lots of power then. Today? Probably $3k-$4k for both from AGon if/when you can find them. Incredibly grainless, powerful, pure...you might even be happy with one but given the numbers you could certainly get both and never worry about power.

 

[LL21]

Yeah, I understand. I'm not a bass freak, per se. But I do like good, powerful bass. Basically, I wanted a Class A amp that's got all of the magic and not too tough on price. That's why First Watt came to mind. We're talking around $5000 for a pair of F4s to run them as balanced XLR bridged monos (100 Wpc into 8 Ohms) vs. $22000 for a pair of XA160.5s. Plus, the First Watt's are built by Nelson himself. I'm already looking to get the XP-25 phono preamp, and that's around $10000. I'm looking at the older X1 preamp as Nelson Pass says in the owners manual (I've been reading that quite a bit) that that will drive the F4s. I imagine the newer XP preamps will as well, but those are a bit too pricey since I really want that XP-25. Also, from what I've read on the First Watt site is that the bridged monos would in fact have enough power, but see for yourself...(read the manual too)

http://www.firstwatt.com/f4.html

Looks pretty impressive...let us know if you get them...seems like it could be exactly what you're looking for.

 

[Dave_A]

They're old, but the Forte 4 was a tremendous Class A 50 watt/channel amp which you could combine with a 2nd...lots of power then. Today? Probably $3k-$4k for both from AGon if/when you can find them. Incredibly grainless, powerful, pure...you might even be happy with one but given the numbers you could certainly get both and never worry about power.

Not interested in something that old.

 

[LL21]

Not interested in something that old.

I have never tried Clayton Audio but read their amps, always Pure Class A, are remarkable. And they can go up to serious power...200 watts+...and cost far far less than a Boulder or Gryphon. Made in Missouri or something.

 

[Dave_A]

I have never tried Clayton Audio but read their amps, always Pure Class A, are remarkable. And they can go up to serious power...200 watts+...and cost far far less than a Boulder or Gryphon. Made in Missouri or something.

Maybe...

 

[Dave_A]

Looks pretty impressive...let us know if you get them...seems like it could be exactly what you're looking for.

I will. Yeah, I hope so!

 

[Dave_A]

So again, has anyone compared First Watt and the XA.5 series?

which sounds better in your opinions?

Thanks again.

 

[KeithR]

So again, has anyone compared First Watt and the XA.5 series?

which sounds better in your opinions?

Thanks again.

FirstWatt SIT1 sounds much better than XA....but wasnt enough power for my 101db speakers in a relatively large room. I clipped around 92dbs. If you have a small room, might work.

 

[Dave_A]

FirstWatt SIT1 sounds much better than XA....but wasnt enough power for my 101db speakers in a relatively large room. I clipped around 92dbs. If you have a small room, might work.

Cool, thanks for your post. I figured that Fiirst Watt would sound better. The model I'm looking at is the F4. 2 for balanced mono which gets you 100 wpc into 8 Ohms. What are your thoughts on that model? Thanks.

http://www.firstwatt.com/f4.html

http://www.firstwatt.com/pdf/prod_f4_man.pdf

 

[PeterA]

FirstWatt SIT1 sounds much better than XA....but wasnt enough power for my 101db speakers in a relatively large room. I clipped around 92dbs. If you have a small room, might work.

Keith, could you describe how they sounded different and which XA.5 model you compared to the SIT1? Thanks.

 

[Dave_A]

Keith, could you describe how they sounded different and which XA.5 model you compared to the SIT1? Thanks.

Good question(s)