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  View original topic: RetroSound + amp
DorianL Sun Sep 14, 2014 2:39 pm

Right-o,

To all the radio heads out there.

I installed the RetroSound radio (4x25 watts) and Hertz component speakers (100 watt continuous, 300 watt peak)


Will this sound ok, or will an amp make a big difference?

Best!

D.

andk5591 Sun Sep 14, 2014 5:09 pm

Unless your car is well insulated, the Retrosound is not going to be real loud. Adding a bigger power amp will help a lot. All depends how picky you are. It will sound OK. It wont sound great.

philermonic Sun Sep 14, 2014 6:26 pm

DorianL wrote: Right-o,

To all the radio heads out there.

I installed the RetroSound radio (4x25 watts) and Hertz component speakers (100 watt continuous, 300 watt peak)


Will this sound ok, or will an amp make a big difference?

Best!

D.

I own the Retrosound Model 1 and have it in the dash of my '62 Ghia.
I really like the variety of inputs it has - SD Card, USB stick, 1/8" mini jacks, as well as it's "quasy-retro" look - a few of it's features are sorta cool too.
While I have a long sound engineer back round, I also know an ACVW is not really much of an environment to listen to music in the 1st place, and I have no intention of installing big amplifiers and a sub woofer.
The Retro Sound has a serviceable set of EQ pre-sets, as well as bass & treble & loudness settings that all do what they are supposed to do.
The sound produced by the stock amplifier through the fiberglass kick panel mounted 6.5" speakers in my car would impress no one.
It will get loud enough to be easily heard at highway speeds with the windows down, but other wise is unremarkable in most audio respects.
If I had access to a period correct mono AM/FM Blaupunct or similar radio I could modify to accept some modern inputs, I would have GLADLY traded this method for it and a modern dual voice coil speaker in the top of dash opening.
So - to answer the question....if you are wanting to produce really loud volume with a ton of bass & treble, you WILL need additional amplification.
By the way - the 4x25 amplifier power rating is probably a bit optimistic too - I know it's what their specs say, but even so that is nothing power-wise when it comes to producing loud, clean audio in any environment.
For the record, the speakers you reference - without my looking them up - will not be very loud as they are likely fairly inefficient - meaning they REQUIRE a fair amount of power to produce.
An under powered amplifier will damage speakers as easily as a huge amplifier, if not easier as the inclination will be to turn it up, producing distortion - square waves instead of clean sine waves - and blow speakers up that way, even high power ones.
My philosophy would be to have a ton more power than a speaker I am using needs.
Bear in mind the more power than needed method has the risk of just blowing the speakers out from "over excursion", but I kinda know what I am doing, so.......
Hope this helps!
Let us know what you end up doing!

DorianL Mon Sep 15, 2014 1:04 am

Thanks gents!

I think you guys are spot on.

I'm not very happy with the setup. Tho I love the components. I think the retrosound radio is great.

I love you can skip songs using the knob. Taking calls is cool too, it displays caller ID and you can answer with turn of knob. To boot, it replaces the stock clock I deleted for oil temp gauge.

I have no doubt the Hertz speaker is good:





When the engine is off and volume on quite low, it's all right. Once you bring volume up a bit, it hardly gets loud and immediately sounds tinny distorting as you get to moderate levels of volume.

The car is indeed noisy, but I would want audio to cleanly overpower that.

Just very surprised it sounds "that bad" to start.

I would have figured retrosound and these speakers would sound decent to start.

andk5591 Mon Sep 15, 2014 4:59 am

I can't read the sensitivity rating, but running a passive crossover sucks up power as well. FYI - the higher the sensitivity, the louder the speaker will be with a given amount of power.

Anyway - there are several ways speaker and amp power are given and usually the manufacturers like to use the bigger one because its more impressive. There is peak to peak, peak and RMS (with RMS being given at a certain level of distrortion) I dont remember the exact formula, but this will give you a rough idea. You can have a speaker or amp that is rated at 200 watts (peak to peak), 100 watts (peak) and 70 watts (0.1% distortion) and all three are correct. RMS is the most accurate. I thing the Retrosound unit actually puts out more like 18 Watts RMS - but not sure. And that aint a lot.

And then speaker placement makes a different - kick panel mounts are shooting the sound at your feet instead of your ears, so that doesnt help. You can buy failry cheap 4 channel 50 watt RMS per channel amps for like $100. Will make a huge difference.

If you want really nice sound, run your small speakers off the front 2 channels and run the other 2 channels mono bridge and power an effcient and small sub (JBL GT080) in a 9 3/4" cube under the rear seat. The sub efficiency is critical to be able to use a smaller amp. I have this set up in 2 cars and it sounds VERY good.

philermonic Mon Sep 15, 2014 7:14 am

DorianL wrote: Thanks gents!

I think you guys are spot on.

I'm not very happy with the setup. Tho I love the components. I think the retrosound radio is great.

I love you can skip songs using the knob. Taking calls is cool too, it displays caller ID and you can answer with turn of knob. To boot, it replaces the stock clock I deleted for oil temp gauge.

I have no doubt the Hertz speaker is good:





When the engine is off and volume on quite low, it's all right. Once you bring volume up a bit, it hardly gets loud and immediately sounds tinny distorting as you get to moderate levels of volume.

The car is indeed noisy, but I would want audio to cleanly overpower that.

Just very surprised it sounds "that bad" to start.

I would have figured retrosound and these speakers would sound decent to start.

I see that your speakers have a sensitivity rating of 92.5 decibels.
As another person posted the crossovers will use up some more of your already very limited amplifier power.
What you are hearing is your amplifier running out of power.
If we go with what you posted as the output per channel - 25 watts - in order for what you are listening to to right now to be twice as loud will require TEN TIMES the amplifier power - 250 watts - and to be twice as loud as that will require 2500 watts, and so on.
The speakers you have with a 92.5 rating are at the inefficient side of the scale.
For example a speaker with a sensitivity rating of 102.5 would be twice as loud with your current amplifier, meaning they require 1/10th the power to be the same volume as you currently experience, and a speaker with an 82.5 sensitivity would require ten times as much power to achieve the same output as you are hearing right now, and in your current set up would be half the output volume of what you have.
The only way to have the "thump & sizzle" in your system you most likely are looking for will be to get a much larger amplifier, probably beginning at 100 to 150 watts per channel, and two to three times that not being excessive.
It can get expensive.
Good luck and let us know how it turns out!

ccihon Mon Sep 15, 2014 10:47 am

All good data, including the detail on efficiency...but one area I would differ with...92.5 is a very efficient rating for a 6.5" speaker - those over-100 numbers generally apply to big-woofer drivers. Take a look around at SPL numbers for multi-driver 6.5-size kick-panel sets and you'll find these to be quite efficient.

I use similar units in fiberglass, poly-filled kick panels in my Ghia, driven only by the head unit, and supplement the bass with a powered Rockford-Fosgate box connected via line-level, mounted behind the seat. I considered a separate 2-channel to drive the kicks but find it plenty loud and plenty clean, even in a noisy car.

One area not mentioned in this thread but appropriately discussed elsewhere is power - if you have the stock generator, you want to calculate the needed output amperage required to drive large-watt amps.....you may need an alternator upgrade depending on how big-boom you go. These old cars originally had lower power usage demands than modern cars do.

andk5591 Mon Sep 15, 2014 4:56 pm

The suggestions I am making is based on someone who wants to retain their hearing. Unless you are pushing tons of bass, the power sucked up by the amp is pretty nominal, but I run alternators in all of my cars, so I do have more than a generator will put out.

swavananda Mon Sep 15, 2014 8:59 pm

I don't always listen to music when i drive my ghia , but when I do , I like it......







3way components upfront ,6x9 rears , separate amp for 10'' subwoofer tucked in back.All equipment is Eclipse brand .

DorianL Wed Sep 24, 2014 5:31 am

Drool - that looks impressive! And... inspiring.

This...



...is too small. It was $170 for 2 x 65W at 4 Ohms. The sales person said it would be sufficient for my application, so I went with it. Mistake! I am not sure he knows much about car audio.

It sounds MUCH better than before (so I know I am on the right track) but you can hear that there simply isn't enough oompfff to power these speakers. Even at the radio's loudest volume, the speakers aren't excessively loud. But I learned something.

Anyway, the dude already agreed to take back his under powered amp and I'll swap it for an HDP-4

http://hertzaudiovideo.eu/hdp-4/



That should net: 2 x 150W at 4Ohms and another 500W left over for a sub.

Stay tuned... (no pun intended)

D

DorianL Thu Sep 25, 2014 12:28 pm

Stupid question... but what does all this stuff DO?!?!?!


andk5591 Fri Sep 26, 2014 4:54 am

Go through the manual, but will try to help and keep it simple.

#1 you have 4 amplifiers in that unit - chanels 1 & 2 and 3 & 4. If a switch is set to stereo for 1 & 2, then the input signal for each side goes to its own amp and then to its own speaker. IF you set 1 & 2 to mono, only one of its inputs functions and you typically have a different speaker connection (see you manual for mono bridge) Mono bridge is a mode where 2 amplifiers work together and work like a single bigger amp. Typically you use this for driving a subwoofer.

#2 You have internal crossovers in the amp. What this means is that you can split the frequencies to go to different speakers. If not using subwoofiers, you just set the switches to full range. IF you are using subs, here is an example of a setting - crossover frequency for BOTH set to 80. The channel(s) driving the subs are set to low pass and the channel(s) driving the other speakers are set to hi pass. What this means is low pass allows Low frequencies (below 80 cycles) to pass through to the amp and speakers. Hi pass, means the High frequencies (above 80 cycles) pass through the amp and to the speakers. Check you multiplier function in the manual - I suspect that it multiplies the frequency and x or 10. For example, if you used a speaker system where you wanted to split the frequencies at 1000 cycles, you would set it to 100X10.

#3 The level control is how loud that particular channel or channels are. Depending on the amp, some work differently. What you want to do is be able to controll the level from your head unit and make it as loud as you want without distortion. IF you have the level on the amp set too low, you will be pushing the head unit into distortion and that will make the amplified signal distorted. If the amp level is too high, your head unit volume may be too touchy.

Does that cover it? Oh - make sure you are using the correct signal to drive your amp - some use the speaker outputs from the head unit and some dont - important you dont screw this up.

philermonic Mon Sep 29, 2014 11:15 pm

You need to understand Unity Gain, and get your components operating at "Unity Gain".
Unity gain is established by calibrating two pieces of equipment to talk at the same level.
Otherwise as the previous poster said, on one side of the equation, your head unit will distort and the overall volume will still be too low.
On the other end, it will be too touchy and a setting of "2" will be VERY loud and you will also have excessive electronic component noise at both ends of the spectrum.
This does not yet cover the intricacies of properly setting the crossover itself.
Done correctly - very often it is not - using this method is by far the most efficient way to use your amplifier power concentrated to the areas that need it the most, and to end up with a balanced, clear "natural" sound that is capable of the highest possible Sound Pressure Levels (SPL) your collection of components are able to deliver.
It is not something I would suggest you try the "hit or miss" method with - bite the bullet and consult a professional and maximize your investment and listening pleasure!

DorianL Tue Sep 30, 2014 2:12 am

Thanks Gents,

There was no owner's manual in the box... just a quick start guide. With a note that for further details I was supposed to consult a page on their website. The page in question is not available.

Anyway I swapped out the old amp and installed a new 1000W amp.



That should do a better job.



It sounds muuuch better now... sometimes.

I've been hit and missing around and so far, I managed to get it sounding fairly decent.

But I agree with you, I think having it professionally tuned is the way to go.

I also tossed a sub in the kitty cradle


andk5591 Tue Sep 30, 2014 5:19 am

OK - So you are feeding the sub though 3&4 mono bridged, correct? Channels 1&2 should be feeding the other speakers. My example above should get you through that set up.

DorianL Tue Sep 30, 2014 5:26 am

andk5591 wrote: OK - So you are feeding the sub though 3&4 mono bridged, correct? Channels 1&2 should be feeding the other speakers. My example above should get you through that set up.

Yeahhhhuuuummmmmmm not that I could quite articulate it that way... :lol: :lol: :lol:

philermonic Tue Sep 30, 2014 8:54 pm

DorianL wrote: andk5591 wrote: OK - So you are feeding the sub though 3&4 mono bridged, correct? Channels 1&2 should be feeding the other speakers. My example above should get you through that set up.

Yeahhhhuuuummmmmmm not that I could quite articulate it that way... :lol: :lol: :lol:

I believe you have the components now to do what you want to do.
I still suggest you find someone - preferably a professional now to complete this installation and in adjusting the crossover.
You'll be a lot happier I think.

DorianL Wed Oct 01, 2014 2:22 am

philermonic wrote: DorianL wrote: andk5591 wrote: OK - So you are feeding the sub though 3&4 mono bridged, correct? Channels 1&2 should be feeding the other speakers. My example above should get you through that set up.

Yeahhhhuuuummmmmmm not that I could quite articulate it that way... :lol: :lol: :lol:

I believe you have the components now to do what you want to do.
I still suggest you find someone - preferably a professional now to complete this installation and in adjusting the crossover.
You'll be a lot happier I think.

Definitely. Agreed!



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