Rank: Member
Groups: Member
Joined: 8/6/2008(UTC)
Posts: 128
Location: Baltimore, MD USA
|
there has been so much discussion about this that I remain a bit confused.
I am presently using an IVY and have a un-completed Legato 2 on the bench with a lagato 3 on order.
I never finished the lagato 2 because of my confusion with which resistor to change to what value to up the stock output voltage. There were post stating just change R1-4 an other that said that to change R25-R26 as well
The new lagato 3 manual touches on this subject just briefly and does not have enough info for me to make any decisions.
can some one please state very clearly which resistors to change to what value on both the lagato 2 and 3 for at lease 2 volts out
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921  Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
From manual:
The output voltage at 0dbfs is about 1.5VRMS. It can be increased to 2VRMS by using R1-R4 of 187Ω.
Please keep in mind that the Legato must be carefully tuned for best THD+N. The supplied values give the
best balance between signal integrity and output voltage I have found so far. It is best not exceed a value of
200R without changing R9-R16.
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN
Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
|
As AVR300 has pointed out, the only resistors you need to change are R1-4 to 187R for 2V, as per the manual.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 7/12/2010(UTC)
Posts: 24
Location: Australia
|
Russ - finding 187R in a 1W Dale is tricky. Can you advise a supplier?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN
Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
|
No need to be exactly 187R. 150 to 200 is just fine.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 7/12/2010(UTC)
Posts: 24
Location: Australia
|
Russ - I hate to be pedantic, but it appears the Dale resistors supplied with the kit are CMF60 series - rated at 0.5 watt (but I understand are good to 1W). If so, I need to look for the CMF60 180 Ohm or similar, rather than the CMF70 series that are huge looking beasts rated at 1W.
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN
Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
|
Well I would try to stick with 1W rating (which CMF60 are except for military purposes). If necessary vertical mount.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 8/6/2008(UTC)
Posts: 128
Location: Baltimore, MD USA
|
I appreciate all your answers but what is confusing is that the manual states in the last section.....
Other Applications
If you want to change the output voltage you need to adjust both the top - I/V (R1-R4) values and bottom -
CCS (R9-R16) values in proportion to each other. I have found that a ratio of 1/4.4 works very well for top
resistor values up to about 364Ω. I have not tried gain any higher than that. If you need to please contact
us.
The Legato is a very flexible circuit. Not every configuration possibility can be covered here. Please visit
the forums if you have any specific application questions.
so according to the above statement
R1-R4 changed to 180 ohms 1 watt
R9-R16 changed to 792 ohms
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 11/21/2008(UTC)
Posts: 314
Location: Norway
|
Russ White wrote:As AVR300 has pointed out, the only resistors you need to change are R1-4 to 187R for 2V, as per the manual. wake up Pelliot! best Leif
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 8/6/2008(UTC)
Posts: 128
Location: Baltimore, MD USA
|
I am awake, are you? Why don't you read the whole manual before flaming me. I saw what the manual said but it also states what I quoted, just asking for clarification
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN
Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
|
That statement is in regard to values that would not be between 150 and 200R. What further information are you needing?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 8/6/2008(UTC)
Posts: 128
Location: Baltimore, MD USA
|
|
|
|
|
|
|
Forum Jump
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.
