Hi Ed, the only way to put three channels on one of those barredboss HS would be to mount them on their sides, which should work fine. I would not go less than 4" in that case, and more like 5-6" would be better.
Cheers!
Russ
Cheers!
Russ
Very happy to report the birth of another Mauro. Its been playing for 30 mins and all seems well; DC offsets were about 2mv and 0.4mv and nothings getting warm. Its nice when things work first time 🙂 🙂 🙂
I can tell already that it's worth far more than it cost; sound is clean and natural, no apparent nasties at all. Its too late to give it any stick, and it must need to burn in a bit so I'll leave further comment on sound till later.
Many thanks guys.
I can tell already that it's worth far more than it cost; sound is clean and natural, no apparent nasties at all. Its too late to give it any stick, and it must need to burn in a bit so I'll leave further comment on sound till later.
Many thanks guys.
Thanks Russ,
The idea I have for their mounting is the center board horizontally, the two outside boards vertically, with the components to the outside. The large E-caps away from each other. Maybe 6" is the better choice.
The idea I have for their mounting is the center board horizontally, the two outside boards vertically, with the components to the outside. The large E-caps away from each other. Maybe 6" is the better choice.
float said:
Hi Float, 🙂
Can't argue with that! 🙂
I am very glad to hear its running! Great work.
Cheers!
Russ
float said:Very happy to report the birth of another Mauro. Its been playing for 30 mins and all seems well; DC offsets were about 2mv and 0.4mv and nothings getting warm. Its nice when things work first time 🙂 🙂 🙂
I can tell already that it's worth far more than it cost; sound is clean and natural, no apparent nasties at all. Its too late to give it any stick, and it must need to burn in a bit so I'll leave further comment on sound till later.
Many thanks guys.
Your case was looking good. Pictures of it complete please! 😉
led's
Can I get some advice and guidance for the selection and use of leds for power-on indcators?
I know there are many colors and levels of brightness. Can the brightness be controlled with a dropping resistor? Do they require a minimum current to come on?
Thanks,
Can I get some advice and guidance for the selection and use of leds for power-on indcators?
I know there are many colors and levels of brightness. Can the brightness be controlled with a dropping resistor? Do they require a minimum current to come on?
Thanks,
rabstg said:
Sorry Troy, but I think you've got me confused with someone else. I can assure you my case has never looked good 😀
I've not posted any pics as yet, but will soon.
I listened to it quietly for about 4 hours last night, and it seemed to be steadily improving. Initially it was sounding a bit small and closed in with a rather reticent bass, but the treble was surprisingly pure and detailed - the shimmer of cymbals was portrayed beautifully. I didn't expect so much here for a brand new amp.
The last thing I played before bed was Nitin Sawnhey's 'Prophesy', and the bass had sure developed some since first listen. I expect more improvement to come.
How long is burn in for these things?
Today looks like a day of work and visitors, so not much chance to play 🙁
Will keep y'all posted
Cheers,
Float
Re: led's
Hi Ed,
I use pretty ordinary bright blue LEDs which don't draw mauch, I think about 10ma.
Look at the specs of the LED and just make sure the resistor(R23) will suplly at least 10% or so of the indicated max current. That is usually enough to turn them on. Some will actually turn on with amazingly little current.
The indicated 6.8K will work for just about any LED, and it is a pretty conservative value. Start with that, if it looks to bright for you (will not likely be too dark) increase the value. I am using 12K in mine as I don't like my LEDs to be too bright, but the 6.8K works fine too. BTW if you go above the 6.8K you can generally use 1/4W resistor measure/calculate actual current draw to be sure.
Cheers!
Russ
Ed Lafontaine said:
Hi Ed,
I use pretty ordinary bright blue LEDs which don't draw mauch, I think about 10ma.
Look at the specs of the LED and just make sure the resistor(R23) will suplly at least 10% or so of the indicated max current. That is usually enough to turn them on. Some will actually turn on with amazingly little current.
The indicated 6.8K will work for just about any LED, and it is a pretty conservative value. Start with that, if it looks to bright for you (will not likely be too dark) increase the value. I am using 12K in mine as I don't like my LEDs to be too bright, but the 6.8K works fine too. BTW if you go above the 6.8K you can generally use 1/4W resistor measure/calculate actual current draw to be sure.
Cheers!
Russ
float said:
Hi Float, I cannot say I have really noticed a major change with burn in, but I would not discount your findings, one thing I do know. This amp has very airy and detailed highs. Sometimes, when you first hear it, it can sort of overwhelm the senses, and it takes a little while for your brain to adjust to the new spectrum of sound. 🙂 When you are hearing things you didn't before, it can make things you always heard before seem smaller, but as you indicated, it all there.
One of the best features of this amp is absolutely tight, and full bass, but it is paired with an extremely flat response (rev C) all the way to the top of the audio spectrum, so "you" are likely being broken in more than the amp. 😉Enjoy the day, maybe you can show off your handywork. 😉
Cheers!
Russ
When I first connected my bedroom speakers they sounded quite good, but over the next few days they progressively got worse..
Wich is a good thing. The speakers are Hi-Vi drivers I stuffed in my old B&W Matrix 805 boxes and are mis-aligned. So as the bass gradually became "even" with the rest of the spectrum the bass hump got progressively worse.
I've never been so happy to have a BAD response. 😀
But again these are basically test speakers also and I will eventually replace them with a better pair.
Wich is a good thing. The speakers are Hi-Vi drivers I stuffed in my old B&W Matrix 805 boxes and are mis-aligned. So as the bass gradually became "even" with the rest of the spectrum the bass hump got progressively worse.
I've never been so happy to have a BAD response. 😀
But again these are basically test speakers also and I will eventually replace them with a better pair.
Re: led's
Ed,
Try to get some diffused blue LEDs. These are T5 size I think. Also get the clips. Fry's here carries a nice one peice clip that locks in the LED. Much easier that the old two part LED holder.
The drill needed is a 17/64 for the clips. The longer lead is always positive. Current is calculated by subtracting 3.5 volts from the supply and then dividing by the dropping resistor.
In the three stereo Mauro's I have built the stock values made the light too bright. Hooked up two LED's in series to make it more safe. Even a diffused LED can do permanent eye damage if level is cranked up too high. About 5 ma is usually plenty.
There is a technical reason why people use the blue, but mine are blue because Nelson Pass uses blue.
Mauro, what color are they in your My_Reference?
George
Ed Lafontaine said:
Ed,
Try to get some diffused blue LEDs. These are T5 size I think. Also get the clips. Fry's here carries a nice one peice clip that locks in the LED. Much easier that the old two part LED holder.
The drill needed is a 17/64 for the clips. The longer lead is always positive. Current is calculated by subtracting 3.5 volts from the supply and then dividing by the dropping resistor.
In the three stereo Mauro's I have built the stock values made the light too bright. Hooked up two LED's in series to make it more safe. Even a diffused LED can do permanent eye damage if level is cranked up too high. About 5 ma is usually plenty.
There is a technical reason why people use the blue, but mine are blue because Nelson Pass uses blue.
Mauro, what color are they in your My_Reference?
George
Hi all,
I used : green led (3mm) for speakers ON led (Conn3 My_ref revA) Iled~= 24V / 6k8 = 3,5mA
and red led (3mm) +6,8Kohm on conn2 (aux PWR conn.) for Power ON status.
If the bright is not adeguate or not "balanced", modified the Rserie...
ciao
Mauro
I used : green led (3mm) for speakers ON led (Conn3 My_ref revA) Iled~= 24V / 6k8 = 3,5mA
and red led (3mm) +6,8Kohm on conn2 (aux PWR conn.) for Power ON status.
If the bright is not adeguate or not "balanced", modified the Rserie...
ciao
Mauro
Hey all,
I have Twisted Pear Audio's Kit of Mauro Penasa's fabuluous RevC mono amps in the post.
Now it's time to get the case etc. together.
There has not been much discussion on the best size of the toroidal transformer that would extract the best from the Amp.
It was mentioned that a 400VA T/F would allow rated output to be achieved.
In Australia I can only find either 300VA or 500VA Toroidals, so I am thinking of buying the 500VA T/F.
Would this be overkill ? Would a 300VA be ample ?
For the case and layout I will follow SOP's (Gerd) lead by using two 12 inch long heat sinks for the sides and a few pieces of aluminium attached to them to form the case.
However I'll also place the Transformer in the same case, to save cost and ease of construction. The T/F will be at the front of the case, and the two mono boards at the back.
I do not think it necessary to mount the Transformer in a separate enclosure, for a power amplifier.
Audie.
I have Twisted Pear Audio's Kit of Mauro Penasa's fabuluous RevC mono amps in the post.
Now it's time to get the case etc. together.
There has not been much discussion on the best size of the toroidal transformer that would extract the best from the Amp.
It was mentioned that a 400VA T/F would allow rated output to be achieved.
In Australia I can only find either 300VA or 500VA Toroidals, so I am thinking of buying the 500VA T/F.
Would this be overkill ? Would a 300VA be ample ?
For the case and layout I will follow SOP's (Gerd) lead by using two 12 inch long heat sinks for the sides and a few pieces of aluminium attached to them to form the case.
However I'll also place the Transformer in the same case, to save cost and ease of construction. The T/F will be at the front of the case, and the two mono boards at the back.
I do not think it necessary to mount the Transformer in a separate enclosure, for a power amplifier.
Audie.
Darn
Now I have to go out and buy all new LED's! BTW, mine are 5mm not T5. I think the T5 are the real big ones.
I messed up and ordered some ultrabright diffused blue in 3 mm. If anyone needs them, let me know vias PM. Led's, like women are warmer in the larger sizes.
George
Now I have to go out and buy all new LED's! BTW, mine are 5mm not T5. I think the T5 are the real big ones.
I messed up and ordered some ultrabright diffused blue in 3 mm. If anyone needs them, let me know vias PM. Led's, like women are warmer in the larger sizes.
George
Audie,
300VA is certainly adequate for two channels. 500VA will give you stiffer rails, but with the current draw of this amp the difference would be minimal.
I would probably go with the 300VA especially if you are looking at size.
Cheers,
Russ
300VA is certainly adequate for two channels. 500VA will give you stiffer rails, but with the current draw of this amp the difference would be minimal.
I would probably go with the 300VA especially if you are looking at size.
Cheers,
Russ
Russ,
Thanks. So 300VA is about right for the Toroidal Transformer.
The 500VA T/F is about 3/4 inch more in diameter and about the same height, so that wouldn't be much of an issue.
It is about 2 pounds heavier and costs about US$15 (AUS$20) more, which might be an issue.
Appreciate your help,
Audie.
Thanks. So 300VA is about right for the Toroidal Transformer.
The 500VA T/F is about 3/4 inch more in diameter and about the same height, so that wouldn't be much of an issue.
It is about 2 pounds heavier and costs about US$15 (AUS$20) more, which might be an issue.
Appreciate your help,
Audie.
Funny about that, as I was thinking along the same lines.
May have to buy a piece, unless I use part of the 2 inch thick laminated Jarrah I was keeping for a possible turntable project.
Comes up well with five coats of varnish.
Audie.
May have to buy a piece, unless I use part of the 2 inch thick laminated Jarrah I was keeping for a possible turntable project.
Comes up well with five coats of varnish.
Audie.