[MrSlim]

Quote:

Originally Posted by cfcubed /img/forum/go_quote.gif . Going take a perfectly good very small hammond enclosure & cut it into 4 pieces (lengthwise along middle sides + top & bottom) to create nice mountable PCB edge brackets. .

Hey, I was thinking about an idea to put two of these in a Hammond 1455T1601 case, which is just over twice as wide and then using 2 or 3 bolts with either nylon spacers or nuts adjusted for the right height to be used as the "slot" in the middle, bolted up through from the bottom..

It might be a fun balanced amp..

 

[HeadphoneAddict]

Quote:

Originally Posted by wiatrob /img/forum/go_quote.gif No need to apologize, your expereince is totally 'bogus' as we say over here!! Take some solace in the fact that the build sounds quite good when it comes together. Driving my Lambdas as loud as I'd like them right now...

How much power does it put out?

 

[holland]

Quote:

Originally Posted by MrSlim /img/forum/go_quote.gif It might be a fun balanced amp..

Indeed.

 

[runeight]

Quote:

Originally Posted by HeadphoneAddict /img/forum/go_quote.gif How much power does it put out?

The buffers can get to about 1V of their rails which would be 11V peak.

For 32R this would be 121 / (2* 32) = 1.9W.

But this is not practical because the amp will be limited by the current sourcing capabilities of the PS. Let's arbitrarily say we can get a maximum of 100mA peak from the PS. We can actually get more, but let's not get greedy.

Then for 32R we have 100mA * 100mA * 32 / 2 = 160mW RMS power.

For 300R we have 121 / (2* 300) = 200mW RMS

These are rough numbers that will vary some from component variations, how well the rail splitter splits 24V to exactly 12V/12V, etc.

 

[wiatrob]

Quote:

Originally Posted by HeadphoneAddict /img/forum/go_quote.gif How much power does it put out?

Technially, the amp was driving the SRD7, driving the lambdas

 

[HeadphoneAddict]

Quote:

Originally Posted by wiatrob /img/forum/go_quote.gif Technially, the amp was driving the SRD7, driving the lambdas

So, how do you get enough power output to drive the SRD-7 SB?

 

[m0b1liz3]

Are we getting close to this being ready as a kit yet

????

 

[nsx_23]

X2 on the kit.

 

[olblueyez]

Kit please!

 

[wiatrob]

Quote:

Originally Posted by HeadphoneAddict /img/forum/go_quote.gif So, how do you get enough power output to drive the SRD-7 SB?

Not knowing that this amp is underpowered for driving a 'stat energiser, I just went ahead and plugged it in. I haven't heard it head to head with more powerful amps yet, the stats just made it home from work...

Probably would benefit from more juice - But it didn't sound too slouchy...

 

[Sancho86]

No need for a kit for me, a PCB will be fantastic

 

[cfcubed]

First wanted to say that very early on I envisioned a small tube amp that delivered desktop-class performance that could be toted around. Talked about that way back in the 2nd post.

We see that it appears to meet the performance goals & here it is meeting the briefcase one:



And this shows why the std design w/recessed tube is something to consider. With about 1/2 the tube below decks the set up is secure enough to travel w/o removing the tube. Been doing this for a week or so & it's all good (std slim briefcase - about 3-1/2" thick). Just make sure your build is secure (no loose solder, metal bits & good solder joints, etc.)

Kits - Runeight, being very conservative & careful with your time and resources, will likely do a "roll call" across the proto builders soon and assess this. Clearly all signs point to good things here.

"Probably would benefit from more juice" - Don't know much about balanced bit but would 2 PCBs in balanced config get what is needed? BTW, could someone point me (PM) to good information on the benefits of balance config w/dynamics?

PCB edge mounts - Thanks for the links holland & alum stock suggestion waitrob... Would like to stick w/metal (I like metal

) & have the $12 little hammond on the way so we'll see. My saws-all w/metal blade would make quick work of things... Love getting destructive w/that thing

 

[holland]

Quote:

Originally Posted by cfcubed /img/forum/go_quote.gif First wanted to say that very early on I envisioned a small tube amp that delivered desktop-class performance that could be toted around.

I absolutely agree. For a transportable that is not a pure portable (mini3 territory), I think this is a *very* nice amp.

Quote:

Originally Posted by cfcubed /img/forum/go_quote.gif With about 1/2 the tube below decks the set up is secure enough to travel w/o removing the tube.

I don't think it's too difficult to remove the tube.

After all the work in building and designing the amp, removing the tube is too much?

I'm just being a PITA.

Quote:

Originally Posted by cfcubed /img/forum/go_quote.gif Kits - Runeight, being very conservative & careful with your time and resources, will likely do a "roll call" across the proto builders soon and assess this. Clearly all signs point to good things here.

I think there should be a limited run of panels and belly plates. My panel work (IMO) really sucked as the top hole is off a bit and just ticks me off when I look at the tube off center. I might go for it too, as I want to build a few of these as gifts. I just hope we could find a good pot (RK27 class) in RK097 form factor. That would just make my day, cause the RK097 is not so good with tracking, albeit better than others I have encountered in that size range (alpha pots, etc.).


Quote:

Originally Posted by cfcubed /img/forum/go_quote.gif Don't know much about balanced bit but would 2 PCBs in balanced config get what is needed?

I doubt it, but I can't say with certainty. The Stax SRD-7 energizer is made for power amps, and IIRC has an internal 24:1 transformer (assume 8ohm input) to convert power amp voltage and current to Stax voltage and current.

The guys working on the electrostatic amp may be able to back calculate the required voltage/current for Stax headphones, apply it through the transformer in the SRD-7 to see how much power is really necessary.

Quote:

Originally Posted by cfcubed /img/forum/go_quote.gif Would like to stick w/metal (I like metal ) & have the $12 little hammond on the way so we'll see.

You're welcome. The context engineering case I used is only $14 and saves you 1 cut as it's a split case.

 

[TimJo]

An update on my amp - last night I got the inputs and outputs wired, and some of the casework finished (well, enough to listen to it anyway

).

All I can say is I stayed up 'till 1:30 in the morning listening, because I just didn't want to stop - this is a good sign of a great amp in my book.

I have only listened using a GE 5814 black plate and my DT880's so far. I've four other tubes sitting there just waiting for a turn, so I'm excited to oblige and let them have a run at it...

I'm hoping to get the rest of the casework and the heater switch installed tonight, and then I'll post some photos.

Here's a sneak peak in the meantime...

 

[cfcubed]

Quote:

Originally Posted by TimJo /img/forum/go_quote.gif < snip > All I can say is I stayed up 'till 1:30 in the morning listening, because I just didn't want to stop - this is a good sign of a great amp in my book.

Very nice looking amp. Great too that it didn't disappoint WRT SQ

I too had a hard time walking away when I 1st heard mine. Think this amp will make waves. Seems all the tubes I tried are "happy" in this amp & the "honored" tubes (Amperex, Siemens, BBs) live up to their reps too.

holland - WRT tubes/holes - I know I posted somewhere about how tube ring / protectors save my butt WRT tube hole centering (from vtc, ebay). I use 1 ring of the 3 in my builds & they mask most any off-center tube hole

Yes, removing the tube is no problem either. Just like one less step in transport

Oh & yes an even better pot than the RK097 that fits in target case would be nice. Don't know if the BoM alt panny EVJ (digikey: P2G1203-ND) is any better...