Best Pre-amp to build for a new DIYer?

[hifimaker]

Hey,

Pardon "newbie" question.... but

I have a Rotel 990BX amp and 970BX pre-amp, and I'm interested in upgrading my pre-amp. Being short on funds and always wanting to build a pre-amp, this seems like a good oportunity to jump in and build one.

My question is: Should I consider building a "Son of Zen" pre-amp or maybe an Aelph P pre-amp?

Any suggestions for a first time build would be appreciated. Also, any recommendations for a PCB source is appreciated.

Thank you,

-David

 

[Nelson Pass]

BSOZ and Aleph P are largely the same preamp. I recommend
BSOZ due to its greater simplicity. You don't want to tackle the
attenuator of the P as a novice.

 

[ElectroNick]

How about the Bride of Zen ?

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Works fine for me ....

Grtz,
Nick

 

[hifimaker]

Nice

WOW, what a nice looking pre-amp. Can't wait to build one of my own.

I'm thinking of building BOSOZ preamp with the Croation PCB's. http://web.vip.hr/pcb-design.vip/bls.html

Someone let me know if there is a better board available.

Thanks for sharing,

-David

 

[hifimaker]

Thank you Mr. Pass

Thank you Mr. Pass for your recommendation. After looking more closely at the designs, the BSOZ does seem more appropriate. Yes, BSOZ and Aleph P are essentially the same preamp.

I appreciate the recommendation.

Now to find the right BSOZ board...

-David

 

[jarek]

BSOZ and Aleph P are largely the same preamp. I recommend BSOZ due to its greater simplicity.

Hi Nelson,
What running temperature do you like for IRF9610’s in BLS? On the board is rather little space for heatsinks. Mosfets go very, very hot. Does this have a important influence on the performance?

 

[BobEllis]

My BoSoZ rund darned hot too. I think that it is higher current that makes for better sound, not temperature. If you can keep the temperature down, it will live longer. With the recommended heat sinks I measured 75C case temperature at +/-62 Volts on the rails and 80 mA draw per channel.

I built my regulators (one pair per channel) with 1x1x1.65" heat sinks - they run less than 50C, they would have been mighty hot with the heat sink called out in the article - about 4 watts if you use a single regulator for both channels.

there is another heat sink that is the same width as the recommended part, but has significantly longer fins(perpendicular to mounting face.) A couple distributors I checked had them. I'm waiting for delivery of some, I hope it is enough. if not, I'll rebuild with the bigger extrusions used in the power supply (and while I am at it change over to CCS).

 

[Squalish]

GILMORE DYNAMIC!!!
Well, perhaps not for newbies. Originally a headphone amp, but can also be used to great affect as a preamp.

The PS is the only thing that needs heatsinks, and even then, four medium-sized to-220 sinks should do good. To cut down on heat a ton, you can safely downgrade the toroid from 35v to either 18v or 22v.

You can protoboard it or buy a PCB on Antness' page.
Around $200 w/ an alps blue($350 w/ a dact) to DIY it.

 

[till]

You don't want to tackle the attenuator of the P as a novice.

what do you think about this as an alternative: http://home.tu-clausthal.de/~tpa/relais/relais.html

BSOZ and Aleph P are largely the same preamp. I recommend BSOZ due to its greater simplicity.

and what about the sound ?

 

[Nickolas K.]

dw8083

Does your Rotel amp have balanced inputs?
Because if it doesn't you don't need a balanced preamp.
Just go for the AlephL.

Nick

 

[B.L.]

How big heatsinks are required for IRFP240 in Aleph P 1.0?

 

[zygibajt]

Does your Rotel amp have balanced inputs?
Because if it doesn't you don't need a balanced preamp.
Just go for the AlephL

Sure go for it.It is simple and outstanding sounding preamp (in my opinion sounds much better than BLS).
And you pretty much don't need to match transistors.
I'm refering to the first-all the time active version of L.
I didn't like the passive/active approach.

How big heatsinks are required for IRFP240 in Aleph P 1.0?

I mounted all of them together with PS transistor on a small heatsink and they barely get warm,so I suppose they would work with no heatsink.But thermally coupling both differential transistors helps.
Bartek

 

[zygibajt]

BSOZ and Aleph P are largely the same preamp. I recommend BSOZ due to its greater simplicity

and what about the sound ?

In my expirence the diffrance between these two is huge.
I consider P outstanding preamp.

But then BLS is much simplier and has advantage of full building manual.Great beginning project!

Bartek

 

[jh6you]

... the diffrance between these two is huge.

Bartek

How different in sound, for example?
As informed by Nelson Pass, main difference is from the P attenuator.

 

[jarek]

As informed by Nelson Pass, main difference is from the P attenuator.

Maybe the attenuator sounds so cool..

 

[zygibajt]

I used the same stepped attenuator at the output in both cases.
And parts were the same (next thing you might want to ask).

But then,this is my point of view.Build both of them and see for yourself.
Bartek

 

[amo]

Hey,

Pardon "newbie" question.... but

I have a Rotel 990BX amp and 970BX pre-amp, and I'm interested in upgrading my pre-amp. Being short on funds and always wanting to build a pre-amp, this seems like a good oportunity to jump in and build one.

My question is: Should I consider building a "Son of Zen" pre-amp or maybe an Aelph P pre-amp?

Any suggestions for a first time build would be appreciated. Also, any recommendations for a PCB source is appreciated.

Thank you,

-David

I am glad I have found this post, becuase I find my self in a very similar situation to dw8083, and thought that BOSOZ would be a great way to enter diy electronics, and in particular PASS diy!

dw- please let me know if you find a better source for the PCBs, other then the one you listed. It would be also interesting to hear where people get their high end pots and chasis, although passdiy site is very interesting in showing how creative people get in this reguard.

Thanks for the info!!

 

[moe29]

Etch your own boards! The artwork is in the BZLS write up. Lots of
people have reccomended Press-n-Peel PCB Blue Transfer Film on
this site Techniks

You probably won't save money doing it this way, but you do get
the "i did that" feeling, plus you have left overs for future projects.

I used the above to make my BZLS boards:

 

[hifimaker]

Everyone,

Thanks for the input and help! Greatly appreciated the useful ideas and suggestions to consider.

Well I decided to build the BOSOZ. I've already ordered a pre-amp and 2 powersupply PCB's from Kristijan in Croatia; at http://web.vip.hr/pcb-design.vip/ .

I'm expecting the boards next week, and will let everyone know if they are any good. The website certainly looks promising.

Moe, Thanks for the PCB etch website. I'd like to try it on my next project

Amo, I'll let you know if I find a good source for the pots or if Kristijan's boards look good. I have not found another source for a BOSOZ board.

Thanks again!

-David

 

[hifimaker]

Everyone,

Thanks for the input and help! Greatly appreciated the useful ideas and suggestions to consider.

Well I decided to build the BOSOZ. I've already ordered a pre-amp and 2 powersupply PCB's from Kristijan in Croatia; at http://web.vip.hr/pcb-design.vip/ .

I'm expecting the boards next week, and will let everyone know if they are any good. The website certainly looks promising.

Moe, Thanks for the PCB etch website. I'd like to try it on my next project

Amo, I'll let you know if I find a good source for the pots or if Kristijan's boards look good. I have not found another source for a BOSOZ board.

Thanks again!

-David