Amp Camp Amp - ACA

[Lugo689]

I just opened up my email and got the message new kits are available I go to sign in on my got in a matter of hours they’re all sold out . I was going to buy two . It is like a popular rock star concert tickets sell out in a matter of minutes . I missed out last time and I missed out this time to . When is the ETA for the next delivery

I was checking the website daily for a couple weeks and I still missed it on the day by a few hours. An approximate ETA could hopefully help me get in on the next round.

 

[MEPER]

I know it works




yup

though , we can go up to 20K , altering two resistors in FB by factor of 2 , but 20K is still too low for pot in front of it

Interesting that you can double the input impedance without affecting the performance of the amp.......maybe I should solder pins in for the two resistors so it is easy to change values.
Why has noone invented an amp where the volumen control is a "native" part of the amp design so you "just" change the gain (without affecting the performance) of the output amp and then always have full signal in from the source. Now we first reduce the input signal and then we amplify the reduced input signal?

 

[Zen Mod]

......(without affecting the performance) .........

it is done numerous times in various gain blocks , not necessary for audio

though , exactly because of your sentence in brackets, we are not doing it routinely ...... you don't want Eq stage , if your goal is to have linear gain

ref. to attached schm , if you want to alter/increase Rin , you must increase R11 and R12 for same amount

example R11 to 20K , R12 to 134K (is that regular value ? first standard ..... 150K is close enough)

 

[MEPER]

it is done numerous times in various gain blocks , not necessary for audio

though , exactly because of your sentence in brackets, we are not doing it routinely ...... you don't want Eq stage , if your goal is to have linear gain

ref. to attached schm , if you want to alter/increase Rin , you must increase R11 and R12 for same amount

example R11 to 20K , R12 to 134K (is that regular value ? first standard ..... 150K is close enough)

Ok...thank you...and changing the values of R11 and R12 will also work with the values in the new design? R11 = 2 x 10 = 20 , R12 = 39,2 x 2 = 78,4 (82k rounded)?

 

[Zen Mod]

where is schm for ACA 2 ?

I believe kacernator altered value to 39K , to accommodate for his needs

 

[mpeg2]

New ACA build instructions?

Rather than procrastinate (like the last few times the ACA kit was available), I pounced immediately when I got the back in stock email.

Is there a pointer to build instructions for the new kit that I could look at while waiting for the order to arrive?

Rich

 

[Spencer Brandsen]

To Zen Mod: I've some circuit boards with 'Nelson Pass Amp Camp EU-1' on it. They have a different size, more square. You can have them if you want.

 

[Zen Mod]

tnx for offer , but I don't need them

I was asking for schm of ACA 2 (can't remember where is it , due to zillion of similar threads ....... or due to my involvement in zillion threads , to be precise) , wishing to be more specific about resistor values , if there is any change from V.1

 

[oks81]

Thinking ACA 2 has drawn in the R15 = 2,2k and R12 changed value to 39,2k.

Look here at 45:30
YouTube

 

[Zen Mod]

aha

it is 10K/39K2 , exactly as in kacernator's schematic few posts above

see : YouTube

 

[MEPER]

Here is schematic 2 ......it was released by 6L6........when ACA was released.


It has lower gain than the original ACA and higher damping factor.


Do you think it is ok also in this schematic to multiply R11, R12 by 2 to get Rin = 20k?

 

[Zen Mod]

yes

 

[kpsthakur]

where is schm for ACA 2 ?

I believe kacernator altered value to 39K , to accommodate for his needs

Zen, does that mean we can use the old version PCB with this schematic without modifying the circuit...just changing the values for these 2 resistors [emoji848]

 

[Dennis Hui]

Yes, old PCB is fine. Just change resistors.

 

[kpsthakur]

Yes, old PCB is fine. Just change resistors.

Thanks Dennis & the PSU would be a 24V 4A+ brick

 

[GnuB]

6L6's build guide will be 98% the same:
ACA illustrated build guide

Rather than procrastinate (like the last few times the ACA kit was available), I pounced immediately when I got the back in stock email.

Is there a pointer to build instructions for the new kit that I could look at while waiting for the order to arrive?

Rich

 

[JamieMcC]

Thanks for your reaction, MEPER. The only source I use is a cd player. What I would like to buy is a class a integrated amp kit with 5 or 6 watts per channel and a good manual. I'm considering an Elekit 8200 (Elekit TU-8200 Stereo Tube Amplifier Kit
| TubeDepot.com) which would suit my needs and costs 699 dollar. But if there was an ACA integrated - with or without a buffer, I don't care as long as it works properly - I would buy it instead of the Elekit. Because probably it would be easier to build and I wouldn't have to buy new tubes every couple of years.

fwiw you might consider the Bottlehead Quickie DHT pre amp kit its only $99 standard or $129 with the PJCCS upgrade (worth having) and very easy to put together.

Its a really nice pairing with the ACA

A full DHT tube / jfet class A system all for just a few hundred dollars...


You are being redirected...

 

[Spencer Brandsen]

Thank you, JamieMcC, for your suggestion, but I'm really looking for a 'one box/no tubes' solution.

 

[mpeg2]

"6L6's build guide will be 98% the same"

GnuB - Thanks - I wasn't sure how much might have changed (besides the obvious bit of 1 chassis vs 2).

Rich

 

[Tom V]

Amp Camp Amp 1.5

The parts have arrived! The case is in Lonate Pozzolo Italy, but is supposed to arrive tomorrow.