USSA-5 Build with Review

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Joined 2007
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Hallo Ernst,

I am in a similar boat: ...... It will be indeed very intersting to read your comparo of the USSA-5 with ....

Claude

Hi Claude,
I'll come back with that at some point of time. I am not an abx test man, and I like to listen to a system for a while and change parts from time to time. Even this is far from being scientific it works for me very well. Means, it will take some time, month.....

I still have to finish the USSA5 amp chassis wise. I'll order a rear plate from a manufacturer, after I will have received my IEC inlet thing and know the dimensions. So hopfully by end of February the amp will be up and running. In the meantime I am going to order the resistors for the USSPA and parts for two BJT capmultiplier (boards by prasi). We will see.

Cheers

Ernst
 
Hi Asanden,

Nice to read this... and also looking to your comparo of USSPA vs Korg... The Korg is attracting me, but it has sadly 16dB gain, so clearly not just a buffer - that's putting me off (more than the 3 caps in the signal path, but then Nelson knows his stuff).

At what position is your volume potentiometer?

Claude

I had my reservations too on the gain and caps, used silmic II with mkp1837, I probably can short the first input ones (will check later) but it is very enjoyable to listen too at Nelson’s recommended settings, used a Salas UltraBiB to power the B1 korg. Used a 50k blue pot on the RCA inputs, I will replace that later with a 20k smd dact.
 
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Hello Project16,

The first I do have already as my daily volume and source control thingie. Mine sits in a solely chassis in order to keep it an just change the preamp part in case of. I really like it!

I like the buffer concept as well, even I haven't planned to build it up to now. I like simple, well designed things, and this seems to be one of this.

So more to do than thought ;-)

Have a nice Sunday :)

Ernst
 

fab

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Joined 2004
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....
I am in a similar boat: I already have too much gain (CD, considering reducing it as listening at 3 O' Clock) or say the rightish gain (Phono), so using a passive pre and not looking to any further......

.... but then with probably a very strong attenuation (depnding on its gain?)
....

Claude

Hi Claude
The USSPA can be configured from 0 (no gain) to about 16db with similar performance. No caps in the signal path.
Fab
 

fab

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Joined 2004
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Hi Gaborbela
Too bad for you it takes so much time to obtain simple 10k pot...

I can put you on the list for the USSPA pcb but since you have many projects ongoing I suppose you are not in a rush to obtain it. In any case, a small batch of 10 pcbs does not cost much since there is a rebates so I can order again if needed - for sure I will not let you down.
Fab
 
Hi Gaborbela
Too bad for you it takes so much time to obtain simple 10k pot...
Fab

Hi Fab
I frustrated about that, I purchased from eBay and waited 2 mounts nothing arrived so at the beginning of January I needed to purchase again.
I did not wanted to order only 2Pc 10K trimmer from Digi-Key because of the shipping cost.
I think I mentioned I am disabled with PTSD and some other stuff so I do not travel especially at winter time. If not I could pick up 2pc at local store. The other thing disability pays very little, so I have to watch how and were I spend. :)
 
Hello Gaborbela,

I can mail you two 10k trimmers if you like? Please let me know and I will include them in my orders.

Bao

Hi
Thank you for your kindness.
OK, I would need 2PC of them.

Who knows if I wait again 2 mounts in vain like last time. :eek:

To those who may doubt my mentioned orders.
Please take a look at the attached pictures
First I purchased at Now 15, never arrived.
Now I purchased again at Jan 16. :) Yes it is frustrating but what can I do about it.
 

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Fab, I asked because I read, that for full power USSA-5 needed just about 1.8V rms. So an active pre would give some more, even if it were a low gain type, which means amplifaction for attenuation.
I'll check what fits better, SALAS DCB1 oder SALAS DCG3, or Whammy or tube, or low resistance lightspeed attenuator.
Your USSPA preamp does look good to me. Are there still some pcbs available? The canadian GB seems to have come to an end as far I could find out with my very limited French.
I would be very interested in building another very nice preamp. And I have the toshibas available :)

Cheers

Ernst

Ciao,

My USSA-5 monoblocks are stretching their legs, they have like 10h of running time. I will write down more details once completed the project, for now I have to say they sound good.

I have tried them with both Salas DCB1 and DCG3 I own and the marriage with the DCG3 gives better results, more clear/open sound in my setup. The pre is set to have a x2 gain which is the min suggested for it.

Emiliano
 

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