The Steel Guitar Forum Store 

Post new topic convert mic input level to guitar input level?
Reply to topic
Author Topic:  convert mic input level to guitar input level?
Dennis Detweiler


From:
Solon, Iowa, US
Post  Posted 14 Jul 2017 8:29 am    
Reply with quote

How do I convert a mic input level on an amp to a guitar input level?
_________________
1976 Birdseye U-12 MSA with Telonics 427 pickup, 1975 Birdseye U-12 MSA with Telonics X-12 pickup, Boss 59 Fender pedal for preamp, NDR-5 Atlantic Delay & Reverb, two Quilter 201 amps, 2- 12" Eminence EPS-12C speakers, ShoBud Pedal, 1949 Epiphone D-8. Revelation preamp into a Crown XLS 1002 power amp.
View user's profile Send private message Send e-mail

Bill Hatcher

 

From:
Atlanta Ga. USA
Post  Posted 14 Jul 2017 9:30 am    
Reply with quote

look at the schematic and see what impedance the input is. if its quarter inch in....thats usually high impedance. plug in and see what it sounds like! you might not have to do anything.

what is the model of the amp? if its a fender....plug in!
View user's profile Send private message Send e-mail

Dennis Detweiler


From:
Solon, Iowa, US
Post  Posted 14 Jul 2017 11:09 am    
Reply with quote

I can't find a schematic anywhere on-line. It's quarter inch input. It's a Lesmann accordion tube amp built in the late 50's to early 60's.
_________________
1976 Birdseye U-12 MSA with Telonics 427 pickup, 1975 Birdseye U-12 MSA with Telonics X-12 pickup, Boss 59 Fender pedal for preamp, NDR-5 Atlantic Delay & Reverb, two Quilter 201 amps, 2- 12" Eminence EPS-12C speakers, ShoBud Pedal, 1949 Epiphone D-8. Revelation preamp into a Crown XLS 1002 power amp.
View user's profile Send private message Send e-mail

Bob Lawrence


From:
Beaver Bank, Nova Scotia, Canada
Post  Posted 14 Jul 2017 3:57 pm    
Reply with quote

Just try it


Have a look at this statement

" this amp makes a fantastic guitar amp when plugged into the microphone input"



Taken from here:

http://www.creamcitymusic.com/vintage-1960-lesmann-accordio-organ-25w-1x15-tube-combo-amp/
_________________
Franklin D10, Telonics (E9)True Tone(C6) pickups, Fender Steel King , Evans (FET 500LV), Nashville 400, Quilter MicroBlock 45 amp's, Telonics FP100 volume pedal, PodXT(effects only), Boss RV3(delay & reverb),Steel Guitar Black Box,Bill Lawrence cables, Walker Seat,Peterson Flip Tuner, IVL Steel Rider, IK Multimedia IRig Pro DUO for recording.
View user's profile Send private message Send e-mail

Dennis Detweiler


From:
Solon, Iowa, US
Post  Posted 15 Jul 2017 1:20 pm    
Reply with quote

Thanks, I'll give it a try. I haven't powered it up yet. I want to check all of the tubes and caps first. The pictured is a different model, but likely the same guts.
_________________
1976 Birdseye U-12 MSA with Telonics 427 pickup, 1975 Birdseye U-12 MSA with Telonics X-12 pickup, Boss 59 Fender pedal for preamp, NDR-5 Atlantic Delay & Reverb, two Quilter 201 amps, 2- 12" Eminence EPS-12C speakers, ShoBud Pedal, 1949 Epiphone D-8. Revelation preamp into a Crown XLS 1002 power amp.
View user's profile Send private message Send e-mail

Bill Hatcher

 

From:
Atlanta Ga. USA
Post  Posted 15 Jul 2017 4:56 pm    
Reply with quote

Dennis Detweiler wrote:
Thanks, I'll give it a try. I haven't powered it up yet. I want to check all of the tubes and caps first. The pictured is a different model, but likely the same guts.


a variac is your best friend when powering up old amps......
View user's profile Send private message Send e-mail

Jack Stoner


From:
Kansas City, MO
Post  Posted 16 Jul 2017 2:16 am    
Reply with quote

Mic level and instrument level are both very low level signals. They should both work however, if its a mic with an XLR connector you will need an adapter to 1/4".
_________________
GFI Ultra Keyless S-10 with pad (Black of course) TB202 amp, Hilton VP, Steelers Choice sidekick seat, SIT Strings
Cakewalk by Bandlab and Studio One V4.6 pro DAWs, MOTU Ultralite MK5 recording interface unit
View user's profile Send private message Send e-mail

Steven Paris

 

From:
Los Angeles
Post  Posted 16 Jul 2017 2:45 am    
Reply with quote

According to published literature from the manufacturers, the "typical" nominal level of a Shure SM-57 dynamic microphone is 1.6mV; Peavey states a nominal input level for an NV400 as 40 mV. So the guitar is generally a bit hotter, but this can vary greatly.
_________________
Emmons & Peavey
View user's profile Send private message Send e-mail

Jack Stoner


From:
Kansas City, MO
Post  Posted 16 Jul 2017 6:01 am    
Reply with quote

Got this from a web page that explains the various levels.

Quote:
Some common levels you'll see:
+4 dBu is "professional" line level, common in modern pro recording gear, and it is about 1.25 V.
0 dBv is an average line level, typical output from rackmount guitar/bass preamps.
-10 dBv is "consumer" line level, common with older and cheaper recording gear.
-20 dBu is roughly in the neighborhood of a typical instrument's output.
-30 dBu is again in the neighborhood of a typical microphone or DI box's output.
However, instruments and microphones can have a very wide range of output levels in reality, so it is most practical to think of instrument-level and mic-level in/outputs as just "a lot lower than line level", rather than calculating specific dB amounts.
 
_________________
GFI Ultra Keyless S-10 with pad (Black of course) TB202 amp, Hilton VP, Steelers Choice sidekick seat, SIT Strings
Cakewalk by Bandlab and Studio One V4.6 pro DAWs, MOTU Ultralite MK5 recording interface unit
View user's profile Send private message Send e-mail

Les Cargill

 

From:
Oklahoma City, Ok, USA
Post  Posted 16 Jul 2017 8:03 am    
Reply with quote

It depends on what you mean by "microphone". I don't rightly know what sort of mic would have traditionally ( from the era the amp was from ) have been used.

FWIW, Ampeg amps often had "accordion" inputs. I wonder if Manley support would know anything; there is a historical connection between them and Ampeg.

Electric guitar pickups can swing a volt, peak to peak. PSG can swing more than that.

If you have a schematic ( and it sounds like you don't ) then any mods would, I would think, follow the usual Fender suspects. For the 5E3 it looks like a 1 M pot and a couple of 68K pots.

But obviously, try it first. If you need padding, I would think about doing that externally. Likewise any buffering or addition of gain could probably be done externally, usually with off the shelf products.
View user's profile Send private message Send e-mail

Dave Grafe


From:
Hudson River Valley NY
Post  Posted 16 Jul 2017 8:11 am    
Reply with quote

The voltage is not as significant as the impedance. 1/4" mic or instrument inputs will be 10k ohms or higher, while an XLR mic input may be in the range of 150 - 600 ohms. You will need a transformer and not just a simple adapter, if you want to plug an XLR mic into a 1/4" input.
View user's profile Send private message Send e-mail Visit poster's website

Jack Stoner


From:
Kansas City, MO
Post  Posted 16 Jul 2017 9:05 am    
Reply with quote

I've connected mic's to guitar inputs. They work OK with an adapter.

Older mic's that were high impedance and have a cable with 1/4" plug attached.
_________________
GFI Ultra Keyless S-10 with pad (Black of course) TB202 amp, Hilton VP, Steelers Choice sidekick seat, SIT Strings
Cakewalk by Bandlab and Studio One V4.6 pro DAWs, MOTU Ultralite MK5 recording interface unit
View user's profile Send private message Send e-mail

Dennis Detweiler


From:
Solon, Iowa, US
Post  Posted 17 Jul 2017 8:55 am    
Reply with quote

This is a 1/4 inch mic input on the amp and wanting to plug a guitar into it.
_________________
1976 Birdseye U-12 MSA with Telonics 427 pickup, 1975 Birdseye U-12 MSA with Telonics X-12 pickup, Boss 59 Fender pedal for preamp, NDR-5 Atlantic Delay & Reverb, two Quilter 201 amps, 2- 12" Eminence EPS-12C speakers, ShoBud Pedal, 1949 Epiphone D-8. Revelation preamp into a Crown XLS 1002 power amp.
View user's profile Send private message Send e-mail

Godfrey Arthur

 

From:
3rd Rock
Post  Posted 23 Aug 2017 9:51 pm    
Reply with quote

Rock guys used to use Bogen PA amps for guitar.

I would just plug in and go for it without over thinking it.

Your guitar's pickups would have an effect on how the input on the amp reacts and if you use pedals, swap guitars it would be a different amp all the same.

Hard to dial in a one size fits all impedance as is the case with most guitar amps anyway made even today.

Not unless you have one of these variable impedance selector thingies:



Little Labs Multi Z PIP



18 watt Bogen HE10 PA amp.
_________________
ShoBud The Pro 1
YES it's my REAL NAME!
Ezekiel 33:7
View user's profile Send private message


All times are GMT - 8 Hours
Jump to:  

Our Online Catalog
Strings, CDs, instruction,
steel guitars & accessories

www.SteelGuitarShopper.com

Please review our Forum Rules and Policies

Steel Guitar Forum LLC
PO Box 237
Mount Horeb, WI 53572 USA


Click Here to Send a Donation

Email admin@steelguitarforum.com for technical support.


BIAB Styles
Ray Price Shuffles for
Band-in-a-Box

by Jim Baron
HTTP