Recommendations for low power SET amps for Avantgarde Duos

[Looser101]

http://glass-ware.stores.yahoo.net/aik9pinsterk.html

[Nanoha]

Too much voltage swing and high noise floor.

Yes. This apparently seems to be the case.

[deepak]

Yes. This apparently seems to be the case.

What the hell? Make up your mind man \

Or are you agreeing just because Kevin Gilmore said that?

It ain't bad. It' ain't bad.

(in response to my asking about the B22 as a pre)

[Nanoha]

What the hell? Make up your mind man \

Or are you agreeing just because Kevin Gilmore said that?

It ain't bad. It definitely had a high noise floor but could still drive the FirstWatt decently.

[deepak]

It ain't bad. It definitely had a high noise floor but could still drive the FirstWatt decently.

Jesus christ... why didn't say that in the first place? A high noise floor makes it worthless as a preamp.

Or wasn't it clear that I'm spending close to $20000 on this setup? I swear to god advice with winking smilies and the such is almost as bad as the crap on Headfi.

[Nanoha]

Wait, what? I thought you were just saving up for a good pre. I was saying you could still use the B22 as a pre and it wouldn't be crap while that happened.

[n_maher]

I'd have to disagree about the high-noise floor statements regarding the beta22. While I'm hardly one to contradict Dr. Gilmore, amb's measurements of the beta seem to indicate that driving just about any load the noise floor is pretty damn low. Perhaps I'm misunderstanding something but it would seem to me that if one was so inclined they could tweak the beta22 configuration to be a hell of a preamp, probably ridiculous overkill, but it could be done easily by lowering the gain and power supply voltage. There is an entire section of the beta22 website dedicated to configuring the design as a preamp. The Dynahi, which becomes unstable at lower gains (or so I'm told) probably would make a much worse preamp.

[deepak]

Wait, what? I thought you were just saving up for a good pre. I was saying you could still use the B22 as a pre and it wouldn't be crap while that happened.

If I was going to even use it temporarily as a preamp I was going to have a remote and ladder attenuator installed while it's still at my builder. Not cheap, that's why I was looking for useful impressions if it was good as a preamp. When I read "it's ain't bad, it ain't bad (with a winking smiley followed up with NO other impressions, or NO mention of the high noise floor)" I'm thinking alright this is going to be pretty good.

I then get advise from someone who knows a hell of a lot more on the subject telling me it will be a pretty bad preamp, and then the original poster who told me it will be a good preamp, follows up with "yeah it has a high noise floor" I'm thinking??

[Nanoha]

Well yes, I'm assuming the typical build of 8x gain. The noise floor was obvious with IEMs out of the Beta22. I still saying the Beta22 won't be a bad preamp (even better with the lower gain) even though there was definitely a noticeable noise floor with the Beta22 I tried. No?

[deepak]

I'd have to disagree about the high-noise floor statements regarding the beta22. While I'm hardly one to contradict Dr. Gilmore, amb's measurements of the beta seem to indicate that driving just about any load the noise floor is pretty damn low. Perhaps I'm misunderstanding something but it would seem to me that if one was so inclined they could tweak the beta22 configuration to be a hell of a preamp, probably ridiculous overkill, but it could be done easily by lowering the gain and power supply voltage. There is an entire section of the beta22 website dedicated to configuring the design as a preamp. The Dynahi, which becomes unstable at lower gains (or so I'm told) probably would make a much worse preamp.

Alright thanks Nate, that's good info.

Unfortunately the Beta is a combination headphone amp/preamp. So it wouldn't be so tweakable. Kevin told me the 3 channel version will cause ground loop problems. And at this stage I'm not willing to make it a 2 channel design.

[Nanoha]

If I was going to even use it temporarily as a preamp I was going to have a remote and ladder attenuator installed while it's still at my builder. Not cheap, that's why I was looking for useful impressions if it was good as a preamp. When I read "it's ain't bad, it ain't bad (with a winking smiley followed up with NO other impressions, or NO mention of the high noise floor)" I'm thinking alright this is going to be pretty good.

I then get advise from someone who knows a hell of a lot more on the subject telling me it will be a pretty bad preamp, and then the original poster who told me it will be a good preamp, follows up with "yeah it has a high noise floor" I'm thinking what???

All right, I'm not one to get into arguments, so I won't say anymore than what I've already said.

[deepak]

Well yes, I'm assuming the typical build of 8x gain. The noise floor was obvious with IEMs out of the Beta22. I still saying the Beta22 won't be a bad preamp (even better with the lower gain) even though there was definitely a noticeable noise floor with the Beta22 I tried. No?

No mention of IEMs here, I read this as it has a high noise floor with the FirstWatt:

It ain't bad. It definitely had a high noise floor but could still drive the FirstWatt decently.

[Nanoha]

No mention of IEMs here, I read this as it has a high noise floor with the FirstWatt:

Ah, I see I see. My mistake there. With IEMs, noticeable (noise issue with high pot setting). With FirstWatt, not there (and drove with no problems with regards to voltage). As I've said, I still believe the Beta22 is not a bad preamp. Not going going back on my opinions there. Just noting that having the Beta22 demonstrate noise issues with IEMs says that the noise is definitely there with the Beta22 I tried.

[deepak]

Ah, I see I see. My mistake.

No problem, sorry about being so harsh. I just get a bit annoyed when it sounds like someone is flip flopping...

[aerius]

Just got back from a visit to head-fi member Roam's place to get my surplus store 2A3's tested. Anyway, a couple more nice choices came up while we were talking.

The Wright Sound AU-10SE is a nice single-ended 300B using the same tubes as the Coincident but with LC coupling like the Cardinal X2 so it can push the 300B into A2 without farting out. It now comes with O-netics transformers made by Bud Purvine, these are really good tranformers.

Also from Wright Sound is the AU-15, which is a push-pull 2A3. Also has O-netics transformers now, though we're not sure if they're Bud's latest version which are said to be kinkless, with effectively no zero-crossing distortion.

[deepak]

Just got back from a visit to head-fi member Roam's place to get my surplus store 2A3's tested. Anyway, a couple more nice choices came up while we were talking.

The Wright Sound AU-10SE is a nice single-ended 300B using the same tubes as the Coincident but with LC coupling like the Cardinal X2 so it can push the 300B into A2 without farting out. It now comes with O-netics transformers made by Bud Purvine, these are really good tranformers.

Also from Wright Sound is the AU-15, which is a push-pull 2A3. Also has O-netics transformers now, though we're not sure if they're Bud's latest version which are said to be kinkless, with effectively no zero-crossing distortion.

Thanks man I appreciate it, very good price too. And they do look better than the Coincidents, but the Wavelength stuff is just dreamy

Any well designed 300B amp should sound good with these speakers.

[iceman94]

Now that we're back to sweet 300B amps, anyone ever hear about or have opinions on Border Patrol? It looks like it'd get along well with the folks here *cough aerius cough*, but who knows. I like the whole power supply-first approach and especially the fact that its a well-finished "exotic" amp that doesn't look like total ass. I can't stand the whole "I'm better because my equipment looks shittier" race- if you're going to live with something long term, there's nothing wrong with investing in cosmetics /rant.

Anyway, the stuff looks sweet on paper and isn't really talked about. Haven't heard it yet, but options are always good.

http://www.borderpatrol.net

[Jon L]

Just got back from a visit to head-fi member Roam's place to get my surplus store 2A3's tested.

http://www.bottlehead.com/et/adobespc/paramourII/paramourII.htm

Before spending some serious $$$ on "brand-name" SET's, especially 300B, I would seriously look into the unassuming Bottlehead Paramour MkII 2A3 SET monoblocks. They've got a good thing going with constant current source driver stage and parafeed output stage.

I have the older MkI and have been listening day and night to it via HE60 and K1000, and I can't believe how good this amp is. The MkII Kit is only $679.

So far all I did was to drop in some cheaper Auricaps into coupling cap position, which made a great thing even greater.

The only other cap in the path is the Parafeed cap, and I think with just 2 caps upgraded to better caps, this thing is just a huge bargain stone cold killer.

So, if you are the type who finds most 300B SET just too colored and/or overpriced (God knows 300B tube itself is just nuts-expensive), a good 2A3 SET may just be up your alley

[humanflyz]

Is 3 watts really enough for K1000s, especially on dynamic music?

[Jon L]

Is 3 watts really enough for K1000s, especially on dynamic music?

I previously didnt' think so. 45 SET at 1.75-2 wpc definitely is not enough.

I believe the reason Paramour does well with K1000 is its topology more than the 2A3 power rating. The C4S constant current loading and parafeed output are supposed to increase bass power and PRAT as well as increased clarity, both of which seem to help satisfy the ears without keep having to turn up the volume b/c you can't hear the details.

I dont' know what kind of music you consider "dynamic," but I listen to pretty much every genre, including classical pieces with wide dynamic range to death metal with no dynamic range but with constant loudness. All fine here...