[johnwmclean]

Voltage Regulator Kit, AC/DC in, DC out, Based on LM317 - eBay (item 260479385900 end time Feb-16-10 05:57:25 PST)

I bought 4 of these, one for each board of my balanced build. They are rated at max current of 1.5A.

I have a question is relation to the calculation of amps, would four heater psu’s rated at 1.5A give a total of 6A?

 

[Ferrari]

Mattias, another (cheaper) alternative is just picking one of this power supply.
Connect a 50W/2x9V toroidal transformer to it and dial the output to 6.3V and you are done.
This PS has two 6.3V outputs (instead of only 1 output of the H-PS-1), use each output for 2 EHHA boards to reduce the heat.

 

[MrMajestic2]

Quote:

Originally Posted by Ferrari /img/forum/go_quote.gif Mattias, another (cheaper) alternative is just picking one of this power supply. Connect a 50W/2x9V toroidal transformer to it and dial the output to 6.3V and you are done. This PS has two 6.3V outputs (instead of only 1 output of the H-PS-1), use each output for 2 EHHA boards to reduce the heat.

That looks nice, I'll go for that one, thanks.

 

[les_garten]

Quote:

Originally Posted by MrMajestic2 /img/forum/go_quote.gif That looks nice, I'll go for that one, thanks.

Check with that vendor. I asked them about this application and believe they told me the current draw was too high for it. Maybe I posed the question incorrectly, who knows.

 

[Ferrari]

Quote:

Originally Posted by les_garten /img/forum/go_quote.gif ... Maybe I posed the question incorrectly, who knows.

Hint: It's based on a pair of LT1083.

How much current does a pair of 6GM8 or 6N30P need ?

 

[dBel84]

Quote:

Originally Posted by aloksatoor /img/forum/go_quote.gif I need recommendations for a decent DC heater supply for the EHHA build m planning. Is the sigma 11 a good one?

I would say that the Sigma 11 is the "ultimate" DC supply for the heaters. It is probably an overkill but if you wanted to build an OTT amp, this would be the way to do it. You have already been given a few options in response to your question. I made mine out of a high current , high speed opamp - OPA548 , just one of many ways to create power supplies.



Seeing as I am posting, I may as well stir the pot as well.

Tube choices::

I have Sachu's EHHA on loan at the moment and I couldn't understand why it sounded lifeless. On a whim I pulled out the Russian 6H30 supertubes and replaced them with a set of amperex 6GM8's - a night and day transformation. I know many folk have reported fantastic things with the 6H30, but my personal experience has not been a positive one with these tubes in this amp. With the 6GM8s the amp shines, has great levels of microdetail and all the slam I could ever want. I am suggesting that new builders keep this in mind and recommend a fair try of the 6GM8 for which this amp was designed. The 6H30 are not only significantly more expensive but need high current heater supplies too. ( 6GM8's are however becoming more pricey themselves. )

..dB

 

[les_garten]

Quote:

Originally Posted by Ferrari /img/forum/go_quote.gif Hint: It's based on a pair of LT1083. How much current does a pair of 6GM8 or 6N30P need ?

I sent them an email asking if it would do 6.3v @ 3.6A and they said it was too close to the thermal envelop. Basically telling me "No", it was not right for my application. I arrived at 3.6A as (.9A x 4 tubes).

Where did I go astray?

It could have been a different product, but I sure think it was that one.

p.s. now I see the difference. I am looking at balanced. That makes the difference of course.

 

[liwei]

Quote:

Originally Posted by johnwmclean /img/forum/go_quote.gif Voltage Regulator Kit, AC/DC in, DC out, Based on LM317 - eBay (item 260479385900 end time Feb-16-10 05:57:25 PST) I bought 4 of these, one for each board of my balanced build. They are rated at max current of 1.5A. I have a question is relation to the calculation of amps, would four heater psu’s rated at 1.5A give a total of 6A?

I also got those regulators a few weeks ago and noticed that the heatsink isn't isolated from the chip. I had an issue with my metal riser touching the heatsink and possibly getting 12 volts.

 

[johnwmclean]

Quote:

Originally Posted by liwei /img/forum/go_quote.gif I also got those regulators a few weeks ago and noticed that the heatsink isn't isolated from the chip. I had an issue with my metal riser touching the heatsink and possibly getting 12 volts.

I noticed there were no isolation pads as well. They are a nice quality build all the same, they have also increased in price since I last bought mine.

 

[jjazzyj]

Quote:

Originally Posted by MrMajestic2 /img/forum/go_quote.gif I was going to go with the Glassware supply, but the shipping to Sweden kind of killed the deal. If I get lazy I might order it anyway though I'm really looking forward to hearing the EHHA after reading all the raves about it.

Embedded Hybrid Headphone Amlifier

Details some easy to build supplies that work just fine. Here's a BOM from digikey for the 12.6V supply.

(4) SB560-E3/51GI-ND 5A 60V Schottky DO201 Diode
(1) 497-3413-5-ND LDO POS ADJ 5A TO-220
(1) 493-1572-ND 4700uF 25V UHE Cap
(1) 493-1549-ND 220uF 25V UHE Cap
(1) 493-1297-ND 10uF 25V UPW Cap
(1) CMF1.82KQFCT-ND 1.82Kohm 1/4w Resistor
(1) CMF200QFCT-ND 200ohm 1/4w Resistor

It would be easy to find parts for the 6.3V version.

 

[MrMajestic2]

Quote:

Originally Posted by jjazzyj /img/forum/go_quote.gif Embedded Hybrid Headphone Amlifier Details some easy to build supplies that work just fine. Here's a BOM from digikey for the 12.6V supply. (4) SB560-E3/51GI-ND 5A 60V Schottky DO201 Diode (1) 497-3413-5-ND LDO POS ADJ 5A TO-220 (1) 493-1572-ND 4700uF 25V UHE Cap (1) 493-1549-ND 220uF 25V UHE Cap (1) 493-1297-ND 10uF 25V UPW Cap (1) CMF1.82KQFCT-ND 1.82Kohm 1/4w Resistor (1) CMF200QFCT-ND 200ohm 1/4w Resistor It would be easy to find parts for the 6.3V version.

Yeah, I have seen that part. I'm just not into bread boarding so I would "have" to order up a board for it. To save myself from that I would like to order a finished product for once

I might end up designing a board anyway, but in that case I'll go for the Pete Millet design.

 

[funch]

If you're interested, I have a couple of breadboarded Millet-circuit
boards similar to the one in my EHHA that I was going to use for
my Bijou, but didn't. PM me if you would like more info.

 

[AffeX]

Quote:

Originally Posted by Ferrari /img/forum/go_quote.gif Mattias, another (cheaper) alternative is just picking one of this power supply. Connect a 50W/2x9V toroidal transformer to it and dial the output to 6.3V and you are done. This PS has two 6.3V outputs (instead of only 1 output of the H-PS-1), use each output for 2 EHHA boards to reduce the heat.

@ les_garten: Each output for two EHHA boards = 4 boards = balanced setup.
But I think you might be right, that 4x0.9A would be a little too much for the device Ferrari points at. Anyway a nice on, thanx for the link Ferrari!

 

[Ferrari]

Quote:

Originally Posted by AffeX /img/forum/go_quote.gif @ les_garten: Each output for two EHHA boards = 4 boards = balanced setup. But I think you might be right, that 4x0.9A would be a little too much for the device Ferrari points at. Anyway a nice on, thanx for the link Ferrari!

I thought it was clear in post #1312.

Once again:

Each LT1083 (7.5A rated) => one 6.3V PS output => connects to 2 EHHA boards which need ~ 2x0.9A = 1.8A max.

Assumming 6N30P tube is used, the 6GM8 needs much less current.
The same is true for both 6.3V PS outputs !!!

In my own balanced EHHA, the mentioned PS is used for 4 pieces 6N30P-DR for a couple of months now

.
And FYI, the measured current needed for a pair of these tubes was ~1.62A.

 

[AffeX]

And now even I get it......ordering one of those today. Thanx Ferrari!

Sorry if I only added confusion. I guess that's the difference of building this amp and actually know what your doing and (like myself) just trying to read all the thousands of posts to try and grasp the good stuff.

I'm planning this amp for a balanced build at the moment and have all the same questions as les_garten, johnwmclean and many other users.
Sadly much of the info available is only about the SE version.

The heater issue just add that little bit of extra complexity.
If only Alex would elaborate the info on the EHHA site and maybe give direct guideline on sourcing the heater current.
In my opinion AMB does this part slightly better documenting builds on his website, and maybe avoiding the same 'stupid' questions over and over in here.

Anyway. EHHA seems to be a fine amp, and I'm going for it.